Merged with trunk revision 600

git-svn-id: svn://localhost/ardour2/branches/midi@601 d708f5d6-7413-0410-9779-e7cbd77b26cf

47 files changed, 2958 insertions, 1808 deletions

diff --git a/libs/ardour/SConscript b/libs/ardour/SConscript
index 33e4633a79..33e40f4230 100644
--- a/libs/ardour/SConscript
+++ b/libs/ardour/SConscript
@@ -27,12 +27,15 @@ ardour.Append(POTFILE = domain + '.pot')
 ardour.Append(CPPPATH = '#libs/surfaces/control_protocol')
 
 ardour_files=Split("""
+audio_diskstream.cc
 audio_library.cc
 audio_playlist.cc
 audio_track.cc
 audioengine.cc
+audiofilesource.cc
 audiofilter.cc
 audioregion.cc
+audiosource.cc
 auditioner.cc
 automation.cc
 automation_event.cc
@@ -44,9 +47,6 @@ curve.cc
 cycle_timer.cc
 default_click.cc
 destructive_filesource.cc
-diskstream.cc
-externalsource.cc
-filesource.cc
 gain.cc
 gdither.cc
 globals.cc
@@ -202,8 +202,8 @@ ardour.Merge ([
 	     libraries['pbd3'],
 	     libraries['soundtouch'],
 	     libraries['midi++2'],
-             libraries['glib2'],
-             libraries['glibmm2']
+	     libraries['glib2'],
+	     libraries['glibmm2']
 	     ])
 
 if ardour['LIBLO']:
diff --git a/libs/ardour/ardour/diskstream.h b/libs/ardour/ardour/audio_diskstream.h
index 316daba52f..9355a3fccb 100644
--- a/libs/ardour/ardour/diskstream.h
+++ b/libs/ardour/ardour/audio_diskstream.h
@@ -15,7 +15,7 @@
     along with this program; if not, write to the Free Software
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 
-    $Id$
+    $Id: diskstream.h 579 2006-06-12 19:56:37Z essej $
 */
 
 #ifndef __ardour_diskstream_h__
@@ -52,10 +52,10 @@ class AudioEngine;
 class Send;
 class Session;
 class AudioPlaylist;
-class FileSource;
+class AudioFileSource;
 class IO;
 
-class DiskStream : public Stateful, public sigc::trackable
+class AudioDiskstream : public Stateful, public sigc::trackable
 {	
   public:
 	enum Flag {
@@ -64,15 +64,15 @@ class DiskStream : public Stateful, public sigc::trackable
 		Destructive = 0x4
 	};
 
-	DiskStream (Session &, const string& name, Flag f = Recordable);
-	DiskStream (Session &, const XMLNode&);
+	AudioDiskstream (Session &, const string& name, Flag f = Recordable);
+	AudioDiskstream (Session &, const XMLNode&);
 
 	string name() const { return _name; }
 
 	ARDOUR::IO* io() const { return _io; }
 	void set_io (ARDOUR::IO& io);
 
-	DiskStream& ref() { _refcnt++; return *this; }
+	AudioDiskstream& ref() { _refcnt++; return *this; }
 	void unref() { if (_refcnt) _refcnt--; if (_refcnt == 0) delete this; }
 	uint32_t refcnt() const { return _refcnt; }
 
@@ -154,7 +154,7 @@ class DiskStream : public Stateful, public sigc::trackable
 
 	AudioPlaylist *playlist () { return _playlist; }
 
-	FileSource *write_source (uint32_t n=0) {
+	AudioFileSource *write_source (uint32_t n=0) {
 		if (n < channels.size())
 			return channels[n].write_source;
 		return 0;
@@ -184,8 +184,8 @@ class DiskStream : public Stateful, public sigc::trackable
 
 	static sigc::signal<void> DiskOverrun;
 	static sigc::signal<void> DiskUnderrun;
-	static sigc::signal<void,DiskStream*> DiskStreamCreated;   // XXX use a ref with sigc2
-	static sigc::signal<void,list<Source*>*> DeleteSources;
+	static sigc::signal<void,AudioDiskstream*> AudioDiskstreamCreated;   // XXX use a ref with sigc2
+	static sigc::signal<void,list<AudioFileSource*>*> DeleteSources;
 
 	/* stateful */
 
@@ -266,7 +266,7 @@ class DiskStream : public Stateful, public sigc::trackable
 
 	/* use unref() to destroy a diskstream */
 
-	~DiskStream();
+	~AudioDiskstream();
 
 	enum TransitionType {
 		CaptureStart = 0,
@@ -288,8 +288,8 @@ class DiskStream : public Stateful, public sigc::trackable
 
 	        float       peak_power;
 
-		FileSource   *fades_source;
-		FileSource   *write_source;
+	        AudioFileSource   *fades_source;
+		AudioFileSource   *write_source;
 
 		Port         *source;
 		Sample       *current_capture_buffer;
@@ -432,7 +432,7 @@ class DiskStream : public Stateful, public sigc::trackable
 	void non_realtime_set_speed ();
 
 	std::list<Region*> _last_capture_regions;
-	std::vector<FileSource*> capturing_sources;
+	std::vector<AudioFileSource*> capturing_sources;
 	int use_pending_capture_data (XMLNode& node);
 
 	void get_input_sources ();
diff --git a/libs/ardour/ardour/audio_track.h b/libs/ardour/ardour/audio_track.h
index c7af9fc5d8..1c17cbc859 100644
--- a/libs/ardour/ardour/audio_track.h
+++ b/libs/ardour/ardour/audio_track.h
@@ -26,7 +26,7 @@
 namespace ARDOUR {
 
 class Session;
-class DiskStream;
+class AudioDiskstream;
 class AudioPlaylist;
 class RouteGroup;
 
@@ -52,8 +52,8 @@ class AudioTrack : public Route
 	bool can_record() const { return true; }
 	void set_record_enable (bool yn, void *src);
 
-	DiskStream& disk_stream() const { return *diskstream; }
-	int set_diskstream (DiskStream&, void *);
+	AudioDiskstream& disk_stream() const { return *diskstream; }
+	int set_diskstream (AudioDiskstream&, void *);
 	int use_diskstream (string name);
 	int use_diskstream (id_t id);
 
@@ -99,7 +99,7 @@ class AudioTrack : public Route
 	void set_meter_point (MeterPoint, void* src);
 
   protected:
-	DiskStream *diskstream;
+	AudioDiskstream *diskstream;
 	MeterPoint _saved_meter_point;
 	TrackMode _mode;
 
diff --git a/libs/ardour/ardour/audiofilesource.h b/libs/ardour/ardour/audiofilesource.h
new file mode 100644
index 0000000000..ecbac569d5
--- /dev/null
+++ b/libs/ardour/ardour/audiofilesource.h
@@ -0,0 +1,157 @@
+/*
+    Copyright (C) 2006 Paul Davis 
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#ifndef __ardour_audiofilesource_h__ 
+#define __ardour_audiofilesource_h__
+
+#include <time.h>
+
+#include <ardour/audiosource.h>
+
+namespace ARDOUR {
+
+struct SoundFileInfo {
+    float       samplerate;
+    uint16_t    channels;
+    int64_t     length;
+    std::string format_name;
+};
+
+class AudioFileSource : public AudioSource {
+  public:
+	enum Flag {
+		Writable = 0x1,
+		CanRename = 0x2,
+		Broadcast = 0x4,
+		Removable = 0x8,
+		RemovableIfEmpty = 0x10,
+		RemoveAtDestroy = 0x20,
+		BuildPeaks = 0x40
+	};
+
+	virtual ~AudioFileSource ();
+
+	int set_name (string newname, bool destructive);
+
+	string path() const { return _path; }
+	string peak_path (string audio_path);
+	string old_peak_path (string audio_path);
+
+	static void set_peak_dir (string dir) { peak_dir = dir; }
+
+	/* factory for an existing but not-used-in-session audio file. this exists
+	   because there maybe multiple back-end derivations of AudioFileSource,
+	   some of which can handle formats that cannot be handled by others.
+	   For example, CoreAudioFileSource can handle MP3 files, which SndFileSource
+	   cannot.
+	 */
+
+	static AudioFileSource* create (string path_plus_channel);
+	static AudioFileSource* create (const XMLNode&);
+
+	static bool get_soundfile_info (string path, SoundFileInfo& _info, string& error);
+
+	void set_allow_remove_if_empty (bool yn);
+	void mark_for_remove();
+
+	/* this block of methods do nothing for regular file sources, but are significant
+	   for files used in destructive recording.
+	*/
+
+	virtual jack_nframes_t last_capture_start_frame() const { return 0; }
+	virtual void           mark_capture_start (jack_nframes_t) {}
+	virtual void           mark_capture_end () {}
+	virtual void           clear_capture_marks() {}
+
+	virtual int update_header (jack_nframes_t when, struct tm&, time_t) = 0;
+	virtual int flush_header () = 0;
+
+	int move_to_trash (const string trash_dir_name);
+
+	static bool is_empty (string path);
+	void mark_streaming_write_completed ();
+
+	void   mark_take (string);
+	string take_id() const { return _take_id; }
+
+	static void set_bwf_country_code (string x);
+	static void set_bwf_organization_code (string x);
+	static void set_bwf_serial_number (int);
+	
+	static void set_search_path (string);
+	static void set_header_position_offset (jack_nframes_t offset, bool negative);
+
+	static sigc::signal<void,struct tm*, time_t> HeaderPositionOffsetChanged;
+
+	XMLNode& get_state ();
+	int set_state (const XMLNode&);
+
+	/* this should really be protected, but C++ is getting stricter
+	   and creating slots from protected member functions is starting
+	   to cause issues.
+	*/
+
+	void handle_header_position_change (struct tm*, time_t tnow);
+
+  protected:
+	
+	/* constructor to be called for existing external-to-session files */
+
+	AudioFileSource (std::string path, Flag flags);
+
+	/* constructor to be called for new in-session files */
+
+	AudioFileSource (std::string path, Flag flags,
+			 SampleFormat samp_format, HeaderFormat hdr_format);
+
+	/* constructor to be called for existing in-session files */
+
+	AudioFileSource (const XMLNode&);
+
+	int init (string idstr, bool must_exist);
+
+	uint16_t       channel;
+	string        _path;
+	Flag          _flags;
+	string        _take_id;
+	bool           allow_remove_if_empty;
+	uint64_t       timeline_position;
+
+	static string peak_dir;
+	static string search_path;
+
+	static char bwf_country_code[3];
+	static char bwf_organization_code[4];
+	static char bwf_serial_number[13];
+
+	static uint64_t header_position_offset;
+	static bool     header_position_negative;
+
+	virtual void set_timeline_position (jack_nframes_t pos);
+	virtual void set_header_timeline_position () = 0;
+
+	bool find (std::string path, bool must_exist, bool& is_new);
+	bool removable() const;
+	bool writable() const { return _flags & Writable; }
+};
+
+}; /* namespace ARDOUR */
+
+#endif /* __ardour_audiofilesource_h__ */
+
diff --git a/libs/ardour/ardour/audiofilter.h b/libs/ardour/ardour/audiofilter.h
index d0fc275cf6..02e5e6f061 100644
--- a/libs/ardour/ardour/audiofilter.h
+++ b/libs/ardour/ardour/audiofilter.h
@@ -28,7 +28,6 @@ namespace ARDOUR {
 
 class AudioRegion;
 class Session;
-class FileSource;
 
 class AudioFilter {
 
@@ -37,7 +36,6 @@ class AudioFilter {
 		: session (s){}
 	virtual ~AudioFilter() {}
 
-
 	virtual int run (ARDOUR::AudioRegion&) = 0;
 	std::vector<ARDOUR::AudioRegion*> results;
 
diff --git a/libs/ardour/ardour/audioregion.h b/libs/ardour/ardour/audioregion.h
index f210fa595b..009aa4b5b0 100644
--- a/libs/ardour/ardour/audioregion.h
+++ b/libs/ardour/ardour/audioregion.h
@@ -27,7 +27,6 @@
 #include <pbd/undo.h>
 
 #include <ardour/ardour.h>
-#include <ardour/source.h>
 #include <ardour/gain.h>
 #include <ardour/region.h>
 #include <ardour/export.h>
@@ -40,6 +39,7 @@ class Route;
 class Playlist;
 class Session;
 class AudioFilter;
+class AudioSource;
 
 struct AudioRegionState : public RegionState 
 {
@@ -56,7 +56,7 @@ struct AudioRegionState : public RegionState
 class AudioRegion : public Region
 {
   public:
-	typedef vector<Source *> SourceList;
+	typedef vector<AudioSource *> SourceList;
 
 	static Change FadeInChanged;
 	static Change FadeOutChanged;
@@ -66,12 +66,12 @@ class AudioRegion : public Region
 	static Change ScaleAmplitudeChanged;
 	static Change EnvelopeChanged;
 
-	AudioRegion (Source&, jack_nframes_t start, jack_nframes_t length, bool announce = true);
-	AudioRegion (Source&, jack_nframes_t start, jack_nframes_t length, const string& name, layer_t = 0, Region::Flag flags = Region::DefaultFlags, bool announce = true);
+	AudioRegion (AudioSource&, jack_nframes_t start, jack_nframes_t length, bool announce = true);
+	AudioRegion (AudioSource&, jack_nframes_t start, jack_nframes_t length, const string& name, layer_t = 0, Region::Flag flags = Region::DefaultFlags, bool announce = true);
 	AudioRegion (SourceList &, jack_nframes_t start, jack_nframes_t length, const string& name, layer_t = 0, Region::Flag flags = Region::DefaultFlags, bool announce = true);
 	AudioRegion (const AudioRegion&, jack_nframes_t start, jack_nframes_t length, const string& name, layer_t = 0, Region::Flag flags = Region::DefaultFlags, bool announce = true);
 	AudioRegion (const AudioRegion&);
-	AudioRegion (Source&, const XMLNode&);
+	AudioRegion (AudioSource&, const XMLNode&);
 	AudioRegion (SourceList &, const XMLNode&);
 	~AudioRegion();
 
@@ -85,7 +85,7 @@ class AudioRegion : public Region
 
 	void lock_sources ();
 	void unlock_sources ();
-	Source& source (uint32_t n=0) const { if (n < sources.size()) return *sources[n]; else return *sources[0]; } 
+	AudioSource& source (uint32_t n=0) const { if (n < sources.size()) return *sources[n]; else return *sources[0]; } 
 
 	void set_scale_amplitude (gain_t);
 	gain_t scale_amplitude() const { return _scale_amplitude; }
diff --git a/libs/ardour/ardour/audiosource.h b/libs/ardour/ardour/audiosource.h
new file mode 100644
index 0000000000..1dcf5b42f3
--- /dev/null
+++ b/libs/ardour/ardour/audiosource.h
@@ -0,0 +1,166 @@
+/*
+    Copyright (C) 2000 Paul Davis 
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+    $Id: audio_source.h 486 2006-04-27 09:04:24Z pauld $
+*/
+
+#ifndef __ardour_audio_source_h__
+#define __ardour_audio_source_h__
+
+#include <list>
+#include <vector>
+#include <string>
+
+#include <time.h>
+
+#include <glibmm/thread.h>
+
+#include <sigc++/signal.h>
+
+#include <ardour/source.h>
+#include <ardour/ardour.h>
+#include <ardour/stateful.h>
+#include <pbd/xml++.h>
+
+using std::list;
+using std::vector;
+using std::string;
+
+namespace ARDOUR {
+
+const jack_nframes_t frames_per_peak = 256;
+
+class AudioSource : public Source
+{
+  public:
+	AudioSource (string name);
+	AudioSource (const XMLNode&);
+	virtual ~AudioSource ();
+
+	/* returns the number of items in this `audio_source' */
+
+	virtual jack_nframes_t length() const {
+		return _length;
+	}
+
+	virtual jack_nframes_t available_peaks (double zoom) const;
+
+	virtual jack_nframes_t read (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const;
+	virtual jack_nframes_t write (Sample *src, jack_nframes_t cnt, char * workbuf);
+
+	virtual float sample_rate () const = 0;
+
+	virtual void mark_for_remove() = 0;
+	virtual void mark_streaming_write_completed () {}
+
+	void set_captured_for (string str) { _captured_for = str; }
+	string captured_for() const { return _captured_for; }
+
+	uint32_t read_data_count() const { return _read_data_count; }
+	uint32_t write_data_count() const { return _write_data_count; }
+
+ 	int  read_peaks (PeakData *peaks, jack_nframes_t npeaks, jack_nframes_t start, jack_nframes_t cnt, double samples_per_unit) const;
+ 	int  build_peaks ();
+	bool peaks_ready (sigc::slot<void>, sigc::connection&) const;
+
+	static sigc::signal<void,AudioSource*> AudioSourceCreated;
+	       
+	mutable sigc::signal<void>  PeaksReady;
+	mutable sigc::signal<void,jack_nframes_t,jack_nframes_t>  PeakRangeReady;
+	
+	XMLNode& get_state ();
+	int set_state (const XMLNode&);
+
+	static int  start_peak_thread ();
+	static void stop_peak_thread ();
+
+	int rename_peakfile (std::string newpath);
+
+	static void set_build_missing_peakfiles (bool yn) {
+		_build_missing_peakfiles = yn;
+	}
+
+	static void set_build_peakfiles (bool yn) {
+		_build_peakfiles = yn;
+	}
+
+  protected:
+	static bool _build_missing_peakfiles;
+	static bool _build_peakfiles;
+
+	bool                _peaks_built;
+	mutable Glib::Mutex _lock;
+	jack_nframes_t      _length;
+	bool                 next_peak_clear_should_notify;
+	string               peakpath;
+	string              _captured_for;
+
+	mutable uint32_t _read_data_count;  // modified in read()
+	mutable uint32_t _write_data_count; // modified in write()
+
+	int initialize_peakfile (bool newfile, string path);
+	void build_peaks_from_scratch ();
+
+	int  do_build_peak (jack_nframes_t, jack_nframes_t);
+
+	virtual jack_nframes_t read_unlocked (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const = 0;
+	virtual jack_nframes_t write_unlocked (Sample *dst, jack_nframes_t cnt, char * workbuf) = 0;
+	virtual string peak_path(string audio_path) = 0;
+	virtual string old_peak_path(string audio_path) = 0;
+	
+	void update_length (jack_nframes_t pos, jack_nframes_t cnt);
+
+	static pthread_t peak_thread;
+	static bool      have_peak_thread;
+	static void*     peak_thread_work(void*);
+
+	static int peak_request_pipe[2];
+
+	struct PeakRequest {
+	    enum Type {
+		    Build,
+		    Quit
+	    };
+	};
+
+	static vector<AudioSource*> pending_peak_sources;
+	static Glib::Mutex* pending_peak_sources_lock;
+
+	static void queue_for_peaks (AudioSource&);
+	static void clear_queue_for_peaks ();
+	
+	struct PeakBuildRecord {
+	    jack_nframes_t frame;
+	    jack_nframes_t cnt;
+
+	    PeakBuildRecord (jack_nframes_t f, jack_nframes_t c) 
+		    : frame (f), cnt (c) {}
+	    PeakBuildRecord (const PeakBuildRecord& other) {
+		    frame = other.frame;
+		    cnt = other.cnt;
+	    }
+	};
+
+	list<AudioSource::PeakBuildRecord *> pending_peak_builds;
+
+  private:
+	bool file_changed (string path);
+};
+
+}
+
+#endif /* __ardour_audio_source_h__ */
diff --git a/libs/ardour/ardour/coreaudio_source.h b/libs/ardour/ardour/coreaudio_source.h
index 736ea32df7..82533de950 100644
--- a/libs/ardour/ardour/coreaudio_source.h
+++ b/libs/ardour/ardour/coreaudio_source.h
@@ -31,8 +31,11 @@ class CoreAudioSource : public ExternalSource {
 	CoreAudioSource (const XMLNode&);
 	~CoreAudioSource ();
 
-	jack_nframes_t read (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const;
 	float sample_rate() const;
+	int update_header (jack_nframes_t when, struct tm&, time_t);
+
+  protected:
+	jack_nframes_t read_unlocked (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const;
 
   private:
 	ExtAudioFileRef af;
diff --git a/libs/ardour/ardour/cycle_timer.h b/libs/ardour/ardour/cycle_timer.h
index 1ec7c74903..b9cbbbf0a8 100644
--- a/libs/ardour/ardour/cycle_timer.h
+++ b/libs/ardour/ardour/cycle_timer.h
@@ -22,29 +22,27 @@
 #define __ardour_cycle_timer_h__
 
 #include <string>
-#include <cstdio>
+#include <iostream>
 
 #include <ardour/cycles.h>
 
-using std::string;
-
 class CycleTimer {
   private:
 	static float cycles_per_usec;
-	uint32_t long entry;
-	uint32_t long exit;
-	string _name;
+	cycles_t _entry;
+	cycles_t _exit;
+	std::string _name;
 	
   public:
-	CycleTimer(string name) : _name (name){
+	CycleTimer(std::string name) : _name (name){
 		if (cycles_per_usec == 0) {
 			cycles_per_usec = get_mhz ();
 		}
-		entry = get_cycles();
+		_entry = get_cycles();
 	}
 	~CycleTimer() {
-		exit = get_cycles();
-		printf ("%s: %.9f usecs (%lu-%lu)\n", _name.c_str(), (float) (exit - entry) / cycles_per_usec, entry, exit);
+		_exit = get_cycles();
+		std::cerr << _name << ": " << (float) (_exit - _entry) / cycles_per_usec << " (" <<  _entry << ", " << _exit << ')' << endl;
 	}
 
 	static float get_mhz ();
diff --git a/libs/ardour/ardour/destructive_filesource.h b/libs/ardour/ardour/destructive_filesource.h
index dbaf379257..49a1e3b48a 100644
--- a/libs/ardour/ardour/destructive_filesource.h
+++ b/libs/ardour/ardour/destructive_filesource.h
@@ -23,30 +23,33 @@
 
 #include <string>
 
-#include <ardour/filesource.h>
+#include <ardour/sndfilesource.h>
 
 struct tm;
 
 namespace ARDOUR {
 
-class DestructiveFileSource : public FileSource {
+class DestructiveFileSource : public SndFileSource {
   public:
-	DestructiveFileSource (std::string path, jack_nframes_t rate, bool repair_first = false, SampleFormat samp_format=FormatInt24);
-	DestructiveFileSource (const XMLNode&, jack_nframes_t rate);
+	DestructiveFileSource (std::string path, SampleFormat samp_format, HeaderFormat hdr_format, jack_nframes_t rate,
+			       Flag flags = AudioFileSource::Flag (AudioFileSource::Writable|
+								   AudioFileSource::BuildPeaks));
+
+	DestructiveFileSource (const XMLNode&);
 	~DestructiveFileSource ();
 
-	int  seek (jack_nframes_t frame);
 	jack_nframes_t last_capture_start_frame() const;
 	void mark_capture_start (jack_nframes_t);
 	void mark_capture_end ();
 	void clear_capture_marks();
 
-	jack_nframes_t write (Sample *src, jack_nframes_t cnt, char * workbuf);
-
 	XMLNode& get_state ();
 
 	static void setup_standard_crossfades (jack_nframes_t sample_rate);
 
+  protected:
+	jack_nframes_t write_unlocked (Sample *src, jack_nframes_t start, jack_nframes_t cnt, char * workbuf);
+
   private:
 	static jack_nframes_t xfade_frames;
 	static gain_t* out_coefficient;
@@ -59,7 +62,7 @@ class DestructiveFileSource : public FileSource {
 	Sample*        xfade_buf;
 
 	jack_nframes_t crossfade (Sample* data, jack_nframes_t cnt, int dir, char * workbuf);
-
+	void set_timeline_position (jack_nframes_t);
 };
 
 }
diff --git a/libs/ardour/ardour/externalsource.h b/libs/ardour/ardour/externalsource.h
deleted file mode 100644
index 17504d0afc..0000000000
--- a/libs/ardour/ardour/externalsource.h
+++ /dev/null
@@ -1,67 +0,0 @@
-/*
-    Copyright (C) 2006 Paul Davis 
-
-    This program is free software; you can redistribute it and/or modify
-    it under the terms of the GNU General Public License as published by
-    the Free Software Foundation; either version 2 of the License, or
-    (at your option) any later version.
-
-    This program is distributed in the hope that it will be useful,
-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    GNU General Public License for more details.
-
-    You should have received a copy of the GNU General Public License
-    along with this program; if not, write to the Free Software
-    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-
-*/
-
-#ifndef __external_source_h__ 
-#define __external_source_h__
-
-#include <ardour/source.h>
-
-namespace ARDOUR {
-
-struct SoundFileInfo {
-    float    samplerate;
-    uint16_t channels;
-    int64_t length;
-    std::string format_name;
-};
-
-class ExternalSource : public Source {
-  public:
-	virtual ~ExternalSource ();
-
-	string path() const { return _path; }
-
-	virtual jack_nframes_t read (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const = 0;
-
-	void mark_for_remove() {} // we never remove external sndfiles 
-	string peak_path(string audio_path);
-	string old_peak_path(string audio_path);
-
-	static void set_peak_dir (string dir) { peak_dir = dir; }
-
-	static ExternalSource* create (const string& path_plus_channel, bool build_peak = true);
-	static ExternalSource* create (const XMLNode& node);
-	static bool get_soundfile_info (string path, SoundFileInfo& _info, string& error);
-
-  protected:
-	ExternalSource (const string& path_plus_channel, bool build_peak = true);
-	ExternalSource (const XMLNode&);
-
-	static string peak_dir;
-
-	uint16_t channel;
-	string  _path;
-
-	jack_nframes_t read_unlocked (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const;
-};
-
-}; /* namespace ARDOUR */
-
-#endif /* __external_source_h__ */
-
diff --git a/libs/ardour/ardour/playlist.h b/libs/ardour/ardour/playlist.h
index d322f564ee..c653c8502e 100644
--- a/libs/ardour/ardour/playlist.h
+++ b/libs/ardour/ardour/playlist.h
@@ -37,7 +37,6 @@
 #include <ardour/crossfade_compare.h>
 #include <ardour/location.h>
 #include <ardour/stateful.h>
-#include <ardour/source.h>
 #include <ardour/state_manager.h>
 
 namespace ARDOUR  {
diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index 9339e448db..0554d13e68 100644
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -62,11 +62,12 @@ namespace ARDOUR {
 class Port;
 class AudioEngine;
 class Slave;
-class DiskStream;	
+class AudioDiskstream;	
 class Route;
 class AuxInput;
 class Source;
-class FileSource;
+class AudioSource;
+class AudioFileSource;
 class Auditioner;
 class Insert;
 class Send;
@@ -263,25 +264,30 @@ class Session : public sigc::trackable, public Stateful
 	vector<Sample*>& get_silent_buffers (uint32_t howmany);
 	vector<Sample*>& get_send_buffers () { return _send_buffers; }
 
-	DiskStream    *diskstream_by_id (id_t id);
-	DiskStream    *diskstream_by_name (string name);
+	AudioDiskstream    *diskstream_by_id (id_t id);
+	AudioDiskstream    *diskstream_by_name (string name);
 
 	bool have_captured() const { return _have_captured; }
 
 	void refill_all_diskstream_buffers ();
 	uint32_t diskstream_buffer_size() const { return dstream_buffer_size; }
-	uint32_t get_next_diskstream_id() const { return n_diskstreams(); }
-	uint32_t n_diskstreams() const;
 	
-	typedef list<DiskStream *> DiskStreamList;
+	/* XXX fix required here when we get new diskstream types *, but
+	   not sure of the direction to take this in until then.
+	*/
+
+	uint32_t get_next_diskstream_id() const { return n_audio_diskstreams(); }
+	uint32_t n_audio_diskstreams() const;
+	
+	typedef list<AudioDiskstream *> AudioDiskstreamList;
 
-	Session::DiskStreamList disk_streams() const {
+	Session::AudioDiskstreamList audio_disk_streams() const {
 		Glib::RWLock::ReaderLock lm (diskstream_lock);
-		return diskstreams; /* XXX yes, force a copy */
+		return audio_diskstreams; /* XXX yes, force a copy */
 	}
 
-	void foreach_diskstream (void (DiskStream::*func)(void));
-	template<class T> void foreach_diskstream (T *obj, void (T::*func)(DiskStream&));
+	void foreach_audio_diskstream (void (AudioDiskstream::*func)(void));
+	template<class T> void foreach_audio_diskstream (T *obj, void (T::*func)(AudioDiskstream&));
 
 	typedef list<Route *> RouteList;
 
@@ -346,7 +352,7 @@ class Session : public sigc::trackable, public Stateful
 	sigc::signal<void> HaltOnXrun;
 
 	sigc::signal<void,Route*> RouteAdded;
-	sigc::signal<void,DiskStream*> DiskStreamAdded;
+	sigc::signal<void,AudioDiskstream*> AudioDiskstreamAdded;
 
 	void request_roll ();
 	void request_bounded_roll (jack_nframes_t start, jack_nframes_t end);
@@ -358,15 +364,15 @@ class Session : public sigc::trackable, public Stateful
 	void goto_start () { request_locate (start_location->start(), false); }
 	void use_rf_shuttle_speed ();
 	void request_transport_speed (float speed);
-	void request_overwrite_buffer (DiskStream*);
-	void request_diskstream_speed (DiskStream&, float speed);
+	void request_overwrite_buffer (AudioDiskstream*);
+	void request_diskstream_speed (AudioDiskstream&, float speed);
 	void request_input_change_handling ();
 
 	bool locate_pending() const { return static_cast<bool>(post_transport_work&PostTransportLocate); }
 	bool transport_locked () const;
 
 	int wipe ();
-	int wipe_diskstream (DiskStream *);
+	int wipe_diskstream (AudioDiskstream *);
 
 	int remove_region_from_region_list (Region&);
 
@@ -603,7 +609,7 @@ class Session : public sigc::trackable, public Stateful
 
 	jack_nframes_t convert_to_frames_at (jack_nframes_t position, AnyTime&);
 
-	sigc::signal<void> SMPTEOffsetChanged;
+	static sigc::signal<void> SMPTEOffsetChanged;
 	sigc::signal<void> SMPTETypeChanged;
 
 	void        request_slave_source (SlaveSource, jack_nframes_t pos = 0);
@@ -659,8 +665,9 @@ class Session : public sigc::trackable, public Stateful
 	int start_audio_export (ARDOUR::AudioExportSpecification&);
 	int stop_audio_export (ARDOUR::AudioExportSpecification&);
 	
-	void add_source (Source *);
-	int  remove_file_source (FileSource&);
+	void add_audio_source (AudioSource *);
+	void remove_source (Source *);
+	int  cleanup_audio_file_source (AudioFileSource&);
 
 	struct cleanup_report {
 	    vector<string> paths;
@@ -692,7 +699,8 @@ class Session : public sigc::trackable, public Stateful
 	sigc::signal<void,Source *> SourceAdded;
 	sigc::signal<void,Source *> SourceRemoved;
 
-	FileSource *create_file_source (ARDOUR::DiskStream&, int32_t chan, bool destructive);
+	AudioFileSource *create_audio_source_for_session (ARDOUR::AudioDiskstream&, uint32_t which_channel, bool destructive);
+
 	Source *get_source (ARDOUR::id_t);
 
 	/* playlist management */
@@ -736,8 +744,8 @@ class Session : public sigc::trackable, public Stateful
 
 	/* flattening stuff */
 
-	int write_one_track (AudioTrack&, jack_nframes_t start, jack_nframes_t cnt, bool overwrite, vector<Source*>&,
-			     InterThreadInfo& wot);
+	int write_one_audio_track (AudioTrack&, jack_nframes_t start, jack_nframes_t cnt, bool overwrite, vector<AudioSource*>&,
+				   InterThreadInfo& wot);
 	int freeze (InterThreadInfo&);
 
 	/* session-wide solo/mute/rec-enable */
@@ -963,7 +971,7 @@ class Session : public sigc::trackable, public Stateful
 	void set_frame_rate (jack_nframes_t nframes);
 
   protected:
-	friend class DiskStream;
+	friend class AudioDiskstream;
 	void stop_butler ();
 	void wait_till_butler_finished();
 
@@ -1422,12 +1430,12 @@ class Session : public sigc::trackable, public Stateful
 	bool waiting_to_start;
 
 	void set_auto_loop (bool yn);
-	void overwrite_some_buffers (DiskStream*);
+	void overwrite_some_buffers (AudioDiskstream*);
 	void flush_all_redirects ();
 	void locate (jack_nframes_t, bool with_roll, bool with_flush, bool with_loop=false);
 	void start_locate (jack_nframes_t, bool with_roll, bool with_flush, bool with_loop=false);
 	void force_locate (jack_nframes_t frame, bool with_roll = false);
-	void set_diskstream_speed (DiskStream*, float speed);
+	void set_diskstream_speed (AudioDiskstream*, float speed);
 	void set_transport_speed (float speed, bool abort = false);
 	void stop_transport (bool abort = false);
 	void start_transport ();
@@ -1458,10 +1466,10 @@ class Session : public sigc::trackable, public Stateful
 
 	/* disk-streams */
 
-	DiskStreamList  diskstreams; 
+	AudioDiskstreamList  audio_diskstreams; 
 	mutable Glib::RWLock diskstream_lock;
 	uint32_t dstream_buffer_size;
-	void add_diskstream (DiskStream*);
+	void add_diskstream (AudioDiskstream*);
 	int  load_diskstreams (const XMLNode&);
 
 	/* routes stuff */
@@ -1503,16 +1511,14 @@ class Session : public sigc::trackable, public Stateful
 
 	/* SOURCES */
 	
-	mutable Glib::Mutex source_lock;
-	typedef std::map<id_t, Source *>    SourceList;
+	mutable Glib::Mutex audio_source_lock;
+	typedef std::map<id_t, AudioSource *>    AudioSourceList;
 
-	SourceList sources;
+	AudioSourceList audio_sources;
 
 	int load_sources (const XMLNode& node);
 	XMLNode& get_sources_as_xml ();
 
-	void remove_source (Source *);
-
 	Source *XMLSourceFactory (const XMLNode&);
 
 	/* PLAYLISTS */
@@ -1531,7 +1537,7 @@ class Session : public sigc::trackable, public Stateful
 	Playlist *XMLPlaylistFactory (const XMLNode&);
 
 	void playlist_length_changed (Playlist *);
-	void diskstream_playlist_changed (DiskStream *);
+	void diskstream_playlist_changed (AudioDiskstream *);
 
 	/* NAMED SELECTIONS */
 
diff --git a/libs/ardour/ardour/session_diskstream.h b/libs/ardour/ardour/session_diskstream.h
index 3c888c92c3..33fc5419ba 100644
--- a/libs/ardour/ardour/session_diskstream.h
+++ b/libs/ardour/ardour/session_diskstream.h
@@ -22,15 +22,15 @@
 #define __ardour_session_diskstream_h__
 
 #include <ardour/session.h>
-#include <ardour/diskstream.h>
+#include <ardour/audio_diskstream.h>
 
 namespace ARDOUR {
 
 template<class T> void 
-Session::foreach_diskstream (T *obj, void (T::*func)(DiskStream&)) 
+Session::foreach_audio_diskstream (T *obj, void (T::*func)(AudioDiskstream&)) 
 {
 	Glib::RWLock::ReaderLock lm (diskstream_lock);
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); i++) {
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); i++) {
 		if (!(*i)->hidden()) {
 			(obj->*func) (**i);
 		}
diff --git a/libs/ardour/ardour/sndfilesource.h b/libs/ardour/ardour/sndfilesource.h
index 5d11c9ef09..d146bb5793 100644
--- a/libs/ardour/ardour/sndfilesource.h
+++ b/libs/ardour/ardour/sndfilesource.h
@@ -23,29 +23,57 @@
 
 #include <sndfile.h>
 
-#include <ardour/externalsource.h>
+#include <ardour/audiofilesource.h>
 
 namespace ARDOUR {
 
-class SndFileSource : public ExternalSource {
+class SndFileSource : public AudioFileSource {
   public:
-	SndFileSource (const string& path_plus_channel, bool build_peak = true);
+	/* constructor to be called for existing external-to-session files */
+
+	SndFileSource (std::string path, Flag flags);
+
+	/* constructor to be called for new in-session files */
+
+	SndFileSource (std::string path, SampleFormat samp_format, HeaderFormat hdr_format, jack_nframes_t rate, 
+		       Flag flags = AudioFileSource::Flag (AudioFileSource::Writable|
+							   AudioFileSource::Removable|
+							   AudioFileSource::RemovableIfEmpty|
+							   AudioFileSource::CanRename|
+							   AudioFileSource::BuildPeaks));
+		       
+	/* constructor to be called for existing in-session files */
+	
 	SndFileSource (const XMLNode&);
+
 	~SndFileSource ();
 
-	jack_nframes_t length() const { return _info.frames; } 
-	jack_nframes_t read (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const;
 	float sample_rate () const;
+	int update_header (jack_nframes_t when, struct tm&, time_t);
+	int flush_header ();
+
+	static Flag default_in_session_flags();
+
+  protected:
+	void set_header_timeline_position ();
+
+	jack_nframes_t read_unlocked (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const;
+	jack_nframes_t write_unlocked (Sample *dst, jack_nframes_t cnt, char * workbuf);
+
+	jack_nframes_t write_float (Sample* data, jack_nframes_t pos, jack_nframes_t cnt);
 
   private:
 	SNDFILE *sf;
 	SF_INFO _info;
+	SF_BROADCAST_INFO *_broadcast_info;
 
-	mutable float *tmpbuf;
-	mutable jack_nframes_t tmpbufsize;
-	mutable Glib::Mutex _tmpbuf_lock;
+	mutable float *interleave_buf;
+	mutable jack_nframes_t interleave_bufsize;
 
-	void init (const string &str, bool build_peak);
+	void init (const string &str);
+	int open();
+	void close();
+	int setup_broadcast_info (jack_nframes_t when, struct tm&, time_t);
 };
 
 }; /* namespace ARDOUR */
diff --git a/libs/ardour/ardour/source.h b/libs/ardour/ardour/source.h
index 3781950fbf..f3133c71cd 100644
--- a/libs/ardour/ardour/source.h
+++ b/libs/ardour/ardour/source.h
@@ -21,166 +21,46 @@
 #ifndef __ardour_source_h__
 #define __ardour_source_h__
 
-#include <list>
-#include <vector>
 #include <string>
 
-#include <ctime>
-
 #include <sigc++/signal.h>
 
-#include <glibmm/thread.h>
-
 #include <ardour/ardour.h>
 #include <ardour/stateful.h>
-#include <pbd/xml++.h>
-
-using std::list;
-using std::vector;
-using std::string;
 
 namespace ARDOUR {
 
-struct PeakData {
-    typedef Sample PeakDatum;
-
-    PeakDatum min;
-    PeakDatum max;
-};
-
-const jack_nframes_t frames_per_peak = 256;
-
 class Source : public Stateful, public sigc::trackable
 {
   public:
-	Source (bool announce=true);
+	Source (std::string name);
 	Source (const XMLNode&);
 	virtual ~Source ();
 
-	const string& name() const { return _name; }
+	std::string name() const { return _name; }
+	int set_name (std::string str, bool destructive);
 
 	ARDOUR::id_t  id() const   { return _id; }
 
-	/* returns the number of items in this `source' */
-
-	virtual jack_nframes_t length() const {
-		return _length;
-	}
-
-	virtual jack_nframes_t available_peaks (double zoom) const;
-
-	virtual jack_nframes_t read (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const {
-		return 0;
-	}
-
-	virtual jack_nframes_t write (Sample *src, jack_nframes_t cnt, char * workbuf) {
-		return 0;
-	}
-
-	virtual float sample_rate () const { return 0; }
-
 	uint32_t use_cnt() const { return _use_cnt; }
 	void use ();
 	void release ();
 
-	virtual void mark_for_remove() = 0;
-	virtual void mark_streaming_write_completed () {}
-
 	time_t timestamp() const { return _timestamp; }
 	void stamp (time_t when) { _timestamp = when; }
 
-	void set_captured_for (string str) { _captured_for = str; }
-	string captured_for() const { return _captured_for; }
-
-	uint32_t read_data_count() const { return _read_data_count; }
-	uint32_t write_data_count() const { return _write_data_count; }
-
- 	int  read_peaks (PeakData *peaks, jack_nframes_t npeaks, jack_nframes_t start, jack_nframes_t cnt, double samples_per_unit) const;
- 	int  build_peaks ();
-	bool peaks_ready (sigc::slot<void>, sigc::connection&) const;
-
-	static sigc::signal<void,Source*> SourceCreated;
-	       
-	sigc::signal<void,Source *> GoingAway;
-	mutable sigc::signal<void>  PeaksReady;
-	mutable sigc::signal<void,jack_nframes_t,jack_nframes_t>  PeakRangeReady;
-	
 	XMLNode& get_state ();
 	int set_state (const XMLNode&);
 
-	static int  start_peak_thread ();
-	static void stop_peak_thread ();
-
-	int rename_peakfile (std::string newpath);
-
-	static void set_build_missing_peakfiles (bool yn) {
-		_build_missing_peakfiles = yn;
-	}
-	static void set_build_peakfiles (bool yn) {
-		_build_peakfiles = yn;
-	}
+	sigc::signal<void,Source *> GoingAway;
 
   protected:
-	static bool _build_missing_peakfiles;
-	static bool _build_peakfiles;
-
 	string            _name;
-	uint32_t     _use_cnt;
-	bool              _peaks_built;
-	mutable Glib::Mutex _lock;
-	jack_nframes_t    _length;
-	bool               next_peak_clear_should_notify;
-	string             peakpath;
+	uint32_t          _use_cnt;
 	time_t            _timestamp;
-	string            _captured_for;
-
-	mutable uint32_t _read_data_count;  // modified in read()
-	mutable uint32_t _write_data_count; // modified in write()
-
-	int initialize_peakfile (bool newfile, string path);
-	void build_peaks_from_scratch ();
-
-	int  do_build_peak (jack_nframes_t, jack_nframes_t);
-	virtual jack_nframes_t read_unlocked (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const = 0;
-	virtual string peak_path(string audio_path) = 0;
-
-	static pthread_t peak_thread;
-	static bool      have_peak_thread;
-	static void*     peak_thread_work(void*);
-
-	static int peak_request_pipe[2];
-
-	struct PeakRequest {
-	    enum Type {
-		    Build,
-		    Quit
-	    };
-	};
-
-	static vector<Source*> pending_peak_sources;
-	static Glib::StaticMutex pending_peak_sources_lock;
-
-	static void queue_for_peaks (Source&);
-	static void clear_queue_for_peaks ();
-	
-	struct PeakBuildRecord {
-	    jack_nframes_t frame;
-	    jack_nframes_t cnt;
-
-	    PeakBuildRecord (jack_nframes_t f, jack_nframes_t c) 
-		    : frame (f), cnt (c) {}
-	    PeakBuildRecord (const PeakBuildRecord& other) {
-		    frame = other.frame;
-		    cnt = other.cnt;
-	    }
-	};
-
-	list<Source::PeakBuildRecord *> pending_peak_builds;
 
   private:
 	ARDOUR::id_t _id;
-	
-	bool file_changed (string path);
 };
 
 }
diff --git a/libs/ardour/ardour/types.h b/libs/ardour/ardour/types.h
index 3d7ab4b59a..cdf71b8cc6 100644
--- a/libs/ardour/ardour/types.h
+++ b/libs/ardour/ardour/types.h
@@ -255,10 +255,18 @@ namespace ARDOUR {
 		BWF,
 		WAVE,
 		WAVE64,
+		CAF,
+		AIFF,
 		iXML,
 		RF64
 	};
 
+	struct PeakData {
+	    typedef Sample PeakDatum;
+	    
+	    PeakDatum min;
+	    PeakDatum max;
+	};
 };
 
 std::istream& operator>>(std::istream& o, ARDOUR::SampleFormat& sf);
diff --git a/libs/ardour/diskstream.cc b/libs/ardour/audio_diskstream.cc
index 90e8387f3f..043b2a1c97 100644
--- a/libs/ardour/diskstream.cc
+++ b/libs/ardour/audio_diskstream.cc
@@ -15,7 +15,7 @@
     along with this program; if not, write to the Free Software
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 
-    $Id$
+    $Id: diskstream.cc 567 2006-06-07 14:54:12Z trutkin $
 */
 
 #include <fstream>
@@ -38,10 +38,10 @@
 
 #include <ardour/ardour.h>
 #include <ardour/audioengine.h>
-#include <ardour/diskstream.h>
+#include <ardour/audio_diskstream.h>
 #include <ardour/utils.h>
 #include <ardour/configuration.h>
-#include <ardour/filesource.h>
+#include <ardour/audiofilesource.h>
 #include <ardour/destructive_filesource.h>
 #include <ardour/send.h>
 #include <ardour/audioplaylist.h>
@@ -54,14 +54,14 @@
 using namespace std;
 using namespace ARDOUR;
 
-jack_nframes_t DiskStream::disk_io_chunk_frames;
+jack_nframes_t AudioDiskstream::disk_io_chunk_frames;
 
-sigc::signal<void,DiskStream*>    DiskStream::DiskStreamCreated;
-sigc::signal<void,list<Source*>*> DiskStream::DeleteSources;
-sigc::signal<void>                DiskStream::DiskOverrun;
-sigc::signal<void>                DiskStream::DiskUnderrun;
+sigc::signal<void,AudioDiskstream*>    AudioDiskstream::AudioDiskstreamCreated;
+sigc::signal<void,list<AudioFileSource*>*> AudioDiskstream::DeleteSources;
+sigc::signal<void>                AudioDiskstream::DiskOverrun;
+sigc::signal<void>                AudioDiskstream::DiskUnderrun;
 
-DiskStream::DiskStream (Session &sess, const string &name, Flag flag)
+AudioDiskstream::AudioDiskstream (Session &sess, const string &name, Flag flag)
 	: _name (name),
 	  _session (sess)
 {
@@ -74,10 +74,10 @@ DiskStream::DiskStream (Session &sess, const string &name, Flag flag)
 
 	in_set_state = false;
 
-	DiskStreamCreated (this); /* EMIT SIGNAL */
+	AudioDiskstreamCreated (this); /* EMIT SIGNAL */
 }
 	
-DiskStream::DiskStream (Session& sess, const XMLNode& node)
+AudioDiskstream::AudioDiskstream (Session& sess, const XMLNode& node)
 	: _session (sess)
 	
 {
@@ -95,11 +95,11 @@ DiskStream::DiskStream (Session& sess, const XMLNode& node)
 		use_destructive_playlist ();
 	}
 
-	DiskStreamCreated (this); /* EMIT SIGNAL */
+	AudioDiskstreamCreated (this); /* EMIT SIGNAL */
 }
 
 void
-DiskStream::init_channel (ChannelInfo &chan)
+AudioDiskstream::init_channel (ChannelInfo &chan)
 {
 	chan.playback_wrap_buffer = 0;
 	chan.capture_wrap_buffer = 0;
@@ -128,7 +128,7 @@ DiskStream::init_channel (ChannelInfo &chan)
 
 
 void
-DiskStream::init (Flag f)
+AudioDiskstream::init (Flag f)
 {
 	_id = new_id();
 	_refcnt = 0;
@@ -185,7 +185,7 @@ DiskStream::init (Flag f)
 }
 
 void
-DiskStream::destroy_channel (ChannelInfo &chan)
+AudioDiskstream::destroy_channel (ChannelInfo &chan)
 {
 	if (chan.write_source) {
 		chan.write_source->release ();
@@ -211,7 +211,7 @@ DiskStream::destroy_channel (ChannelInfo &chan)
 	chan.capture_buf = 0;
 }
 
-DiskStream::~DiskStream ()
+AudioDiskstream::~AudioDiskstream ()
 {
 	Glib::Mutex::Lock lm (state_lock);
 
@@ -227,7 +227,7 @@ DiskStream::~DiskStream ()
 }
 
 void
-DiskStream::handle_input_change (IOChange change, void *src)
+AudioDiskstream::handle_input_change (IOChange change, void *src)
 {
 	Glib::Mutex::Lock lm (state_lock);
 
@@ -238,7 +238,7 @@ DiskStream::handle_input_change (IOChange change, void *src)
 }
 
 void
-DiskStream::non_realtime_input_change ()
+AudioDiskstream::non_realtime_input_change ()
 {
 	{ 
 		Glib::Mutex::Lock lm (state_lock);
@@ -299,7 +299,7 @@ DiskStream::non_realtime_input_change ()
 }
 
 void
-DiskStream::get_input_sources ()
+AudioDiskstream::get_input_sources ()
 {
 	uint32_t ni = _io->n_inputs();
 	
@@ -327,18 +327,18 @@ DiskStream::get_input_sources ()
 }		
 
 int
-DiskStream::find_and_use_playlist (const string& name)
+AudioDiskstream::find_and_use_playlist (const string& name)
 {
 	Playlist* pl;
 	AudioPlaylist* playlist;
 		
 	if ((pl = _session.get_playlist (name)) == 0) {
-		error << string_compose(_("DiskStream: Session doesn't know about a Playlist called \"%1\""), name) << endmsg;
+		error << string_compose(_("AudioDiskstream: Session doesn't know about a Playlist called \"%1\""), name) << endmsg;
 		return -1;
 	}
 
 	if ((playlist = dynamic_cast<AudioPlaylist*> (pl)) == 0) {
-		error << string_compose(_("DiskStream: Playlist \"%1\" isn't an audio playlist"), name) << endmsg;
+		error << string_compose(_("AudioDiskstream: Playlist \"%1\" isn't an audio playlist"), name) << endmsg;
 		return -1;
 	}
 
@@ -346,7 +346,7 @@ DiskStream::find_and_use_playlist (const string& name)
 }
 
 int
-DiskStream::use_playlist (AudioPlaylist* playlist)
+AudioDiskstream::use_playlist (AudioPlaylist* playlist)
 {
 	{
 		Glib::Mutex::Lock lm (state_lock);
@@ -370,9 +370,9 @@ DiskStream::use_playlist (AudioPlaylist* playlist)
 			reset_write_sources (false);
 		}
 		
-		plstate_connection = _playlist->StateChanged.connect (mem_fun (*this, &DiskStream::playlist_changed));
-		plmod_connection = _playlist->Modified.connect (mem_fun (*this, &DiskStream::playlist_modified));
-		plgone_connection = _playlist->GoingAway.connect (mem_fun (*this, &DiskStream::playlist_deleted));
+		plstate_connection = _playlist->StateChanged.connect (mem_fun (*this, &AudioDiskstream::playlist_changed));
+		plmod_connection = _playlist->Modified.connect (mem_fun (*this, &AudioDiskstream::playlist_modified));
+		plgone_connection = _playlist->GoingAway.connect (mem_fun (*this, &AudioDiskstream::playlist_deleted));
 	}
 
 	if (!overwrite_queued) {
@@ -387,7 +387,7 @@ DiskStream::use_playlist (AudioPlaylist* playlist)
 }
 
 void
-DiskStream::playlist_deleted (Playlist* pl)
+AudioDiskstream::playlist_deleted (Playlist* pl)
 {
 	/* this catches an ordering issue with session destruction. playlists 
 	   are destroyed before diskstreams. we have to invalidate any handles
@@ -398,7 +398,7 @@ DiskStream::playlist_deleted (Playlist* pl)
 }
 
 int
-DiskStream::use_new_playlist ()
+AudioDiskstream::use_new_playlist ()
 {
 	string newname;
 	AudioPlaylist* playlist;
@@ -422,14 +422,14 @@ DiskStream::use_new_playlist ()
 }
 
 int
-DiskStream::use_copy_playlist ()
+AudioDiskstream::use_copy_playlist ()
 {
 	if (destructive()) {
 		return 0;
 	}
 
 	if (_playlist == 0) {
-		error << string_compose(_("DiskStream %1: there is no existing playlist to make a copy of!"), _name) << endmsg;
+		error << string_compose(_("AudioDiskstream %1: there is no existing playlist to make a copy of!"), _name) << endmsg;
 		return -1;
 	}
 
@@ -447,7 +447,7 @@ DiskStream::use_copy_playlist ()
 }
 
 void
-DiskStream::setup_destructive_playlist ()
+AudioDiskstream::setup_destructive_playlist ()
 {
 	AudioRegion::SourceList srcs;
 
@@ -462,7 +462,7 @@ DiskStream::setup_destructive_playlist ()
 }
 
 void
-DiskStream::use_destructive_playlist ()
+AudioDiskstream::use_destructive_playlist ()
 {
 	/* use the sources associated with the single full-extent region */
 	
@@ -485,7 +485,7 @@ DiskStream::use_destructive_playlist ()
 	ChannelList::iterator chan;
 
 	for (n = 0, chan = channels.begin(); chan != channels.end(); ++chan, ++n) {
-		(*chan).write_source = dynamic_cast<FileSource*>(&region->source (n));
+		(*chan).write_source = dynamic_cast<AudioFileSource*>(&region->source (n));
 		(*chan).write_source->set_allow_remove_if_empty (false);
 	}
 
@@ -493,14 +493,14 @@ DiskStream::use_destructive_playlist ()
 }
 
 void
-DiskStream::set_io (IO& io)
+AudioDiskstream::set_io (IO& io)
 {
 	_io = &io;
 	set_align_style_from_io ();
 }
 
 int
-DiskStream::set_name (string str, void *src)
+AudioDiskstream::set_name (string str, void *src)
 {
 	if (str != _name) {
 		_playlist->set_name (str);
@@ -518,7 +518,7 @@ DiskStream::set_name (string str, void *src)
 }
 
 void
-DiskStream::set_speed (double sp)
+AudioDiskstream::set_speed (double sp)
 {
 	_session.request_diskstream_speed (*this, sp);
 
@@ -527,7 +527,7 @@ DiskStream::set_speed (double sp)
 }
 
 bool
-DiskStream::realtime_set_speed (double sp, bool global)
+AudioDiskstream::realtime_set_speed (double sp, bool global)
 {
 	bool changed = false;
 	double new_speed = sp * _session.transport_speed();
@@ -561,7 +561,7 @@ DiskStream::realtime_set_speed (double sp, bool global)
 }
 
 void
-DiskStream::non_realtime_set_speed ()
+AudioDiskstream::non_realtime_set_speed ()
 {
 	if (_buffer_reallocation_required)
 	{
@@ -584,14 +584,14 @@ DiskStream::non_realtime_set_speed ()
 }
 
 void
-DiskStream::prepare ()
+AudioDiskstream::prepare ()
 {
 	_processed = false;
 	playback_distance = 0;
 }
 
 void
-DiskStream::check_record_status (jack_nframes_t transport_frame, jack_nframes_t nframes, bool can_record)
+AudioDiskstream::check_record_status (jack_nframes_t transport_frame, jack_nframes_t nframes, bool can_record)
 {
 	int possibly_recording;
 	int rolling;
@@ -716,7 +716,7 @@ DiskStream::check_record_status (jack_nframes_t transport_frame, jack_nframes_t
 }
 
 int
-DiskStream::process (jack_nframes_t transport_frame, jack_nframes_t nframes, jack_nframes_t offset, bool can_record, bool rec_monitors_input)
+AudioDiskstream::process (jack_nframes_t transport_frame, jack_nframes_t nframes, jack_nframes_t offset, bool can_record, bool rec_monitors_input)
 {
 	uint32_t n;
 	ChannelList::iterator c;
@@ -731,7 +731,7 @@ DiskStream::process (jack_nframes_t transport_frame, jack_nframes_t nframes, jac
 	   just return. this allows multiple routes that are taking input
 	   from this diskstream to call our ::process() method, but have
 	   this stuff only happen once. more commonly, it allows both
-	   the AudioTrack that is using this DiskStream *and* the Session
+	   the AudioTrack that is using this AudioDiskstream *and* the Session
 	   to call process() without problems.
 	*/
 
@@ -748,7 +748,7 @@ DiskStream::process (jack_nframes_t transport_frame, jack_nframes_t nframes, jac
 		return 0;
 	}
 
-	/* This lock is held until the end of DiskStream::commit, so these two functions
+	/* This lock is held until the end of AudioDiskstream::commit, so these two functions
 	   must always be called as a pair. The only exception is if this function
 	   returns a non-zero value, in which case, ::commit should not be called.
 	*/
@@ -1010,14 +1010,14 @@ DiskStream::process (jack_nframes_t transport_frame, jack_nframes_t nframes, jac
 }
 
 void
-DiskStream::recover ()
+AudioDiskstream::recover ()
 {
 	state_lock.unlock();
 	_processed = false;
 }
 
 bool
-DiskStream::commit (jack_nframes_t nframes)
+AudioDiskstream::commit (jack_nframes_t nframes)
 {
 	bool need_butler = false;
 
@@ -1056,7 +1056,7 @@ DiskStream::commit (jack_nframes_t nframes)
 }
 
 void
-DiskStream::set_pending_overwrite (bool yn)
+AudioDiskstream::set_pending_overwrite (bool yn)
 {
 	/* called from audio thread, so we can use the read ptr and playback sample as we wish */
 	
@@ -1067,7 +1067,7 @@ DiskStream::set_pending_overwrite (bool yn)
 }
 
 int
-DiskStream::overwrite_existing_buffers ()
+AudioDiskstream::overwrite_existing_buffers ()
 {
  	Sample* mixdown_buffer;
  	float* gain_buffer;
@@ -1110,7 +1110,7 @@ DiskStream::overwrite_existing_buffers ()
 
 		if (read ((*chan).playback_buf->buffer() + overwrite_offset, mixdown_buffer, gain_buffer, workbuf,
 			  start, to_read, *chan, n, reversed)) {
-			error << string_compose(_("DiskStream %1: when refilling, cannot read %2 from playlist at frame %3"),
+			error << string_compose(_("AudioDiskstream %1: when refilling, cannot read %2 from playlist at frame %3"),
 					 _id, size, playback_sample) << endmsg;
 			goto out;
 		}
@@ -1121,7 +1121,7 @@ DiskStream::overwrite_existing_buffers ()
 		
 			if (read ((*chan).playback_buf->buffer(), mixdown_buffer, gain_buffer, workbuf,
 				  start, cnt, *chan, n, reversed)) {
-				error << string_compose(_("DiskStream %1: when refilling, cannot read %2 from playlist at frame %3"),
+				error << string_compose(_("AudioDiskstream %1: when refilling, cannot read %2 from playlist at frame %3"),
 						 _id, size, playback_sample) << endmsg;
 				goto out;
 			}
@@ -1139,7 +1139,7 @@ DiskStream::overwrite_existing_buffers ()
 }
 
 int
-DiskStream::seek (jack_nframes_t frame, bool complete_refill)
+AudioDiskstream::seek (jack_nframes_t frame, bool complete_refill)
 {
 	Glib::Mutex::Lock lm (state_lock);
 	uint32_t n;
@@ -1149,9 +1149,6 @@ DiskStream::seek (jack_nframes_t frame, bool complete_refill)
 	for (n = 0, chan = channels.begin(); chan != channels.end(); ++chan, ++n) {
 		(*chan).playback_buf->reset ();
 		(*chan).capture_buf->reset ();
-		if ((*chan).write_source) {
-			(*chan).write_source->seek (frame);
-		}
 	}
 	
 	playback_sample = frame;
@@ -1167,7 +1164,7 @@ DiskStream::seek (jack_nframes_t frame, bool complete_refill)
 }
 
 int
-DiskStream::can_internal_playback_seek (jack_nframes_t distance)
+AudioDiskstream::can_internal_playback_seek (jack_nframes_t distance)
 {
 	ChannelList::iterator chan;
 
@@ -1180,7 +1177,7 @@ DiskStream::can_internal_playback_seek (jack_nframes_t distance)
 }
 
 int
-DiskStream::internal_playback_seek (jack_nframes_t distance)
+AudioDiskstream::internal_playback_seek (jack_nframes_t distance)
 {
 	ChannelList::iterator chan;
 
@@ -1195,7 +1192,7 @@ DiskStream::internal_playback_seek (jack_nframes_t distance)
 }
 
 int
-DiskStream::read (Sample* buf, Sample* mixdown_buffer, float* gain_buffer, char * workbuf, jack_nframes_t& start, jack_nframes_t cnt, 
+AudioDiskstream::read (Sample* buf, Sample* mixdown_buffer, float* gain_buffer, char * workbuf, jack_nframes_t& start, jack_nframes_t cnt, 
 		  ChannelInfo& channel_info, int channel, bool reversed)
 {
 	jack_nframes_t this_read = 0;
@@ -1253,7 +1250,7 @@ DiskStream::read (Sample* buf, Sample* mixdown_buffer, float* gain_buffer, char
 		this_read = min(cnt,this_read);
 
 		if (_playlist->read (buf+offset, mixdown_buffer, gain_buffer, workbuf, start, this_read, channel) != this_read) {
-			error << string_compose(_("DiskStream %1: cannot read %2 from playlist at frame %3"), _id, this_read, 
+			error << string_compose(_("AudioDiskstream %1: cannot read %2 from playlist at frame %3"), _id, this_read, 
 					 start) << endmsg;
 			return -1;
 		}
@@ -1286,7 +1283,7 @@ DiskStream::read (Sample* buf, Sample* mixdown_buffer, float* gain_buffer, char
 }
 
 int
-DiskStream::do_refill (Sample* mixdown_buffer, float* gain_buffer, char * workbuf)
+AudioDiskstream::do_refill (Sample* mixdown_buffer, float* gain_buffer, char * workbuf)
 {
 	int32_t ret = 0;
 	jack_nframes_t to_read;
@@ -1516,7 +1513,7 @@ DiskStream::do_refill (Sample* mixdown_buffer, float* gain_buffer, char * workbu
 }	
 
 int
-DiskStream::do_flush (char * workbuf, bool force_flush)
+AudioDiskstream::do_flush (char * workbuf, bool force_flush)
 {
 	uint32_t to_write;
 	int32_t ret = 0;
@@ -1620,7 +1617,7 @@ DiskStream::do_flush (char * workbuf, bool force_flush)
 		}
 
 		if ((!(*chan).write_source) || (*chan).write_source->write (vector.buf[0], to_write, workbuf) != to_write) {
-			error << string_compose(_("DiskStream %1: cannot write to disk"), _id) << endmsg;
+			error << string_compose(_("AudioDiskstream %1: cannot write to disk"), _id) << endmsg;
 			return -1;
 		}
 
@@ -1637,7 +1634,7 @@ DiskStream::do_flush (char * workbuf, bool force_flush)
 			to_write = min ((jack_nframes_t)(disk_io_chunk_frames - to_write), (jack_nframes_t) vector.len[1]);
 		
 			if ((*chan).write_source->write (vector.buf[1], to_write, workbuf) != to_write) {
-				error << string_compose(_("DiskStream %1: cannot write to disk"), _id) << endmsg;
+				error << string_compose(_("AudioDiskstream %1: cannot write to disk"), _id) << endmsg;
 				return -1;
 			}
 
@@ -1653,13 +1650,13 @@ DiskStream::do_flush (char * workbuf, bool force_flush)
 }
 
 void
-DiskStream::playlist_changed (Change ignored)
+AudioDiskstream::playlist_changed (Change ignored)
 {
 	playlist_modified ();
 }
 
 void
-DiskStream::playlist_modified ()
+AudioDiskstream::playlist_modified ()
 {
 	if (!i_am_the_modifier && !overwrite_queued) {
 		_session.request_overwrite_buffer (this);
@@ -1668,7 +1665,7 @@ DiskStream::playlist_modified ()
 }
 
 void
-DiskStream::transport_stopped (struct tm& when, time_t twhen, bool abort_capture)
+AudioDiskstream::transport_stopped (struct tm& when, time_t twhen, bool abort_capture)
 {
 	uint32_t buffer_position;
 	bool more_work = true;
@@ -1680,7 +1677,7 @@ DiskStream::transport_stopped (struct tm& when, time_t twhen, bool abort_capture
 	ChannelList::iterator chan;
 	vector<CaptureInfo*>::iterator ci;
 	uint32_t n = 0; 
-	list<Source*>* deletion_list;
+	list<AudioFileSource*>* deletion_list;
 	bool mark_write_completed = false;
 
 	finish_capture (true);
@@ -1697,7 +1694,7 @@ DiskStream::transport_stopped (struct tm& when, time_t twhen, bool abort_capture
 		case 1:
 			break;
 		case -1:
-			error << string_compose(_("DiskStream \"%1\": cannot flush captured data to disk!"), _name) << endmsg;
+			error << string_compose(_("AudioDiskstream \"%1\": cannot flush captured data to disk!"), _name) << endmsg;
 			err++;
 		}
 	}
@@ -1713,7 +1710,7 @@ DiskStream::transport_stopped (struct tm& when, time_t twhen, bool abort_capture
 		
 		ChannelList::iterator chan;
 		
-		deletion_list = new list<Source*>;
+		deletion_list = new list<AudioFileSource*>;
 
 		for ( chan = channels.begin(); chan != channels.end(); ++chan) {
 
@@ -1747,15 +1744,15 @@ DiskStream::transport_stopped (struct tm& when, time_t twhen, bool abort_capture
 
 	for (n = 0, chan = channels.begin(); chan != channels.end(); ++chan, ++n) {
 
-		Source* s = (*chan).write_source;
+		AudioFileSource* s = (*chan).write_source;
 		
 		if (s) {
 
-			FileSource* fsrc;
+			AudioFileSource* fsrc;
 
 			srcs.push_back (s);
 
-			if ((fsrc = dynamic_cast<FileSource *>(s)) != 0) {
+			if ((fsrc = dynamic_cast<AudioFileSource *>(s)) != 0) {
 				fsrc->update_header (capture_info.front()->start, when, twhen);
 			}
 
@@ -1817,7 +1814,7 @@ DiskStream::transport_stopped (struct tm& when, time_t twhen, bool abort_capture
 			}
 			
 			catch (failed_constructor& err) {
-				error << _("DiskStream: could not create region for captured audio!") << endmsg;
+				error << _("AudioDiskstream: could not create region for captured audio!") << endmsg;
 				continue; /* XXX is this OK? */
 			}
 			
@@ -1850,7 +1847,7 @@ DiskStream::transport_stopped (struct tm& when, time_t twhen, bool abort_capture
 }
 
 void
-DiskStream::finish_capture (bool rec_monitors_input)
+AudioDiskstream::finish_capture (bool rec_monitors_input)
 {
 	was_recording = false;
 	
@@ -1899,7 +1896,7 @@ DiskStream::finish_capture (bool rec_monitors_input)
 }
 
 void
-DiskStream::set_record_enabled (bool yn, void* src)
+AudioDiskstream::set_record_enabled (bool yn, void* src)
 {
         bool rolling = _session.transport_speed() != 0.0f;
 
@@ -1958,9 +1955,9 @@ DiskStream::set_record_enabled (bool yn, void* src)
 }
 
 XMLNode&
-DiskStream::get_state ()
+AudioDiskstream::get_state ()
 {
-	XMLNode* node = new XMLNode ("DiskStream");
+	XMLNode* node = new XMLNode ("AudioDiskstream");
 	char buf[64];
 	LocaleGuard lg (X_("POSIX"));
 
@@ -1984,7 +1981,7 @@ DiskStream::get_state ()
 		XMLNode* cs_child = new XMLNode (X_("CapturingSources"));
 		XMLNode* cs_grandchild;
 
-		for (vector<FileSource*>::iterator i = capturing_sources.begin(); i != capturing_sources.end(); ++i) {
+		for (vector<AudioFileSource*>::iterator i = capturing_sources.begin(); i != capturing_sources.end(); ++i) {
 			cs_grandchild = new XMLNode (X_("file"));
 			cs_grandchild->add_property (X_("path"), (*i)->path());
 			cs_child->add_child_nocopy (*cs_grandchild);
@@ -2012,7 +2009,7 @@ DiskStream::get_state ()
 }
 
 int
-DiskStream::set_state (const XMLNode& node)
+AudioDiskstream::set_state (const XMLNode& node)
 {
 	const XMLProperty* prop;
 	XMLNodeList nlist = node.children();
@@ -2137,14 +2134,14 @@ DiskStream::set_state (const XMLNode& node)
 }
 
 int
-DiskStream::use_new_write_source (uint32_t n)
+AudioDiskstream::use_new_write_source (uint32_t n)
 {
 	if (!recordable()) {
 		return 1;
 	}
 
 	if (n >= channels.size()) {
-		error << string_compose (_("DiskStream: channel %1 out of range"), n) << endmsg;
+		error << string_compose (_("AudioDiskstream: channel %1 out of range"), n) << endmsg;
 		return -1;
 	}
 
@@ -2152,7 +2149,7 @@ DiskStream::use_new_write_source (uint32_t n)
 	
 	if (chan.write_source) {
 
-		if (FileSource::is_empty (chan.write_source->path())) {
+		if (AudioFileSource::is_empty (chan.write_source->path())) {
 			chan.write_source->mark_for_remove ();
 			chan.write_source->release();
 			delete chan.write_source;
@@ -2163,7 +2160,7 @@ DiskStream::use_new_write_source (uint32_t n)
 	}
 
 	try {
-		if ((chan.write_source = _session.create_file_source (*this, n, destructive())) == 0) {
+		if ((chan.write_source = _session.create_audio_source_for_session (*this, n, destructive())) == 0) {
 			throw failed_constructor();
 		}
 	} 
@@ -2184,7 +2181,7 @@ DiskStream::use_new_write_source (uint32_t n)
 }
 
 void
-DiskStream::reset_write_sources (bool mark_write_complete, bool force)
+AudioDiskstream::reset_write_sources (bool mark_write_complete, bool force)
 {
 	ChannelList::iterator chan;
 	uint32_t n;
@@ -2227,7 +2224,7 @@ DiskStream::reset_write_sources (bool mark_write_complete, bool force)
 }
 
 int
-DiskStream::rename_write_sources ()
+AudioDiskstream::rename_write_sources ()
 {
 	ChannelList::iterator chan;
 	uint32_t n;
@@ -2243,7 +2240,7 @@ DiskStream::rename_write_sources ()
 }
 
 void
-DiskStream::set_block_size (jack_nframes_t nframes)
+AudioDiskstream::set_block_size (jack_nframes_t nframes)
 {
 	if (_session.get_block_size() > speed_buffer_size) {
 		speed_buffer_size = _session.get_block_size();
@@ -2257,7 +2254,7 @@ DiskStream::set_block_size (jack_nframes_t nframes)
 }
 
 void
-DiskStream::allocate_temporary_buffers ()
+AudioDiskstream::allocate_temporary_buffers ()
 {
 	/* make sure the wrap buffer is at least large enough to deal
 	   with the speeds up to 1.2, to allow for micro-variation
@@ -2281,7 +2278,7 @@ DiskStream::allocate_temporary_buffers ()
 }
 
 void
-DiskStream::monitor_input (bool yn)
+AudioDiskstream::monitor_input (bool yn)
 {
 	for (ChannelList::iterator chan = channels.begin(); chan != channels.end(); ++chan) {
 		
@@ -2292,7 +2289,7 @@ DiskStream::monitor_input (bool yn)
 }
 
 void
-DiskStream::set_capture_offset ()
+AudioDiskstream::set_capture_offset ()
 {
 	if (_io == 0) {
 		/* can't capture, so forget it */
@@ -2303,13 +2300,13 @@ DiskStream::set_capture_offset ()
 }
 
 void
-DiskStream::set_persistent_align_style (AlignStyle a)
+AudioDiskstream::set_persistent_align_style (AlignStyle a)
 {
 	_persistent_alignment_style = a;
 }
 
 void
-DiskStream::set_align_style_from_io ()
+AudioDiskstream::set_align_style_from_io ()
 {
 	bool have_physical = false;
 
@@ -2334,7 +2331,7 @@ DiskStream::set_align_style_from_io ()
 }
 
 void
-DiskStream::set_align_style (AlignStyle a)
+AudioDiskstream::set_align_style (AlignStyle a)
 {
 	if (record_enabled() && _session.actively_recording()) {
 		return;
@@ -2348,7 +2345,7 @@ DiskStream::set_align_style (AlignStyle a)
 }
 
 int
-DiskStream::add_channel ()
+AudioDiskstream::add_channel ()
 {
 	/* XXX need to take lock??? */
 
@@ -2368,7 +2365,7 @@ DiskStream::add_channel ()
 }
 
 int
-DiskStream::remove_channel ()
+AudioDiskstream::remove_channel ()
 {
 	if (channels.size() > 1) {
 		/* XXX need to take lock??? */
@@ -2384,21 +2381,21 @@ DiskStream::remove_channel ()
 }
 
 float
-DiskStream::playback_buffer_load () const
+AudioDiskstream::playback_buffer_load () const
 {
 	return (float) ((double) channels.front().playback_buf->read_space()/
 			(double) channels.front().playback_buf->bufsize());
 }
 
 float
-DiskStream::capture_buffer_load () const
+AudioDiskstream::capture_buffer_load () const
 {
 	return (float) ((double) channels.front().capture_buf->write_space()/
 			(double) channels.front().capture_buf->bufsize());
 }
 
 int
-DiskStream::set_loop (Location *location)
+AudioDiskstream::set_loop (Location *location)
 {
 	if (location) {
 		if (location->start() >= location->end()) {
@@ -2414,7 +2411,7 @@ DiskStream::set_loop (Location *location)
 }
 
 jack_nframes_t
-DiskStream::get_capture_start_frame (uint32_t n)
+AudioDiskstream::get_capture_start_frame (uint32_t n)
 {
 	Glib::Mutex::Lock lm (capture_info_lock);
 
@@ -2427,7 +2424,7 @@ DiskStream::get_capture_start_frame (uint32_t n)
 }
 
 jack_nframes_t
-DiskStream::get_captured_frames (uint32_t n)
+AudioDiskstream::get_captured_frames (uint32_t n)
 {
 	Glib::Mutex::Lock lm (capture_info_lock);
 
@@ -2440,23 +2437,23 @@ DiskStream::get_captured_frames (uint32_t n)
 }
 
 void
-DiskStream::punch_in ()
+AudioDiskstream::punch_in ()
 {
 }
 
 void
-DiskStream::punch_out ()
+AudioDiskstream::punch_out ()
 {
 }
 
 int
-DiskStream::use_pending_capture_data (XMLNode& node)
+AudioDiskstream::use_pending_capture_data (XMLNode& node)
 {
 	const XMLProperty* prop;
 	XMLNodeList nlist = node.children();
 	XMLNodeIterator niter;
-	FileSource* fs;
-	FileSource* first_fs = 0;
+	AudioFileSource* fs;
+	AudioFileSource* first_fs = 0;
 	AudioRegion::SourceList pending_sources;
 	jack_nframes_t position;
 
@@ -2476,7 +2473,10 @@ DiskStream::use_pending_capture_data (XMLNode& node)
 			}
 
 			try {
-				fs = new FileSource (prop->value(), _session.frame_rate(), true, Config->get_native_file_data_format());
+				fs = new SndFileSource (prop->value(), 
+							Config->get_native_file_data_format(),
+							Config->get_native_file_header_format(),
+							_session.frame_rate());
 			}
 
 			catch (failed_constructor& err) {
@@ -2543,13 +2543,13 @@ DiskStream::use_pending_capture_data (XMLNode& node)
 }
 
 void
-DiskStream::set_roll_delay (jack_nframes_t nframes)
+AudioDiskstream::set_roll_delay (jack_nframes_t nframes)
 {
 	_roll_delay = nframes;
 }
 
 void
-DiskStream::set_destructive (bool yn)
+AudioDiskstream::set_destructive (bool yn)
 {
 	if (yn != destructive()) {
 		reset_write_sources (true, true);
diff --git a/libs/ardour/audio_track.cc b/libs/ardour/audio_track.cc
index 30adc54d1a..d146b92a4b 100644
--- a/libs/ardour/audio_track.cc
+++ b/libs/ardour/audio_track.cc
@@ -23,10 +23,11 @@
 #include <sigc++/bind.h>
 
 #include <ardour/audio_track.h>
-#include <ardour/diskstream.h>
+#include <ardour/audio_diskstream.h>
 #include <ardour/session.h>
 #include <ardour/redirect.h>
 #include <ardour/audioregion.h>
+#include <ardour/audiosource.h>
 #include <ardour/route_group_specialized.h>
 #include <ardour/insert.h>
 #include <ardour/audioplaylist.h>
@@ -43,19 +44,19 @@ AudioTrack::AudioTrack (Session& sess, string name, Route::Flag flag, TrackMode
 	  diskstream (0),
 	  _midi_rec_enable_control (*this, _session.midi_port())
 {
-	DiskStream::Flag dflags = DiskStream::Flag (0);
+	AudioDiskstream::Flag dflags = AudioDiskstream::Flag (0);
 
 	if (_flags & Hidden) {
-		dflags = DiskStream::Flag (dflags | DiskStream::Hidden);
+		dflags = AudioDiskstream::Flag (dflags | AudioDiskstream::Hidden);
 	} else {
-		dflags = DiskStream::Flag (dflags | DiskStream::Recordable);
+		dflags = AudioDiskstream::Flag (dflags | AudioDiskstream::Recordable);
 	}
 
 	if (mode == Destructive) {
-		dflags = DiskStream::Flag (dflags | DiskStream::Destructive);
+		dflags = AudioDiskstream::Flag (dflags | AudioDiskstream::Destructive);
 	}
 
-	DiskStream* ds = new DiskStream (_session, name, dflags);
+	AudioDiskstream* ds = new AudioDiskstream (_session, name, dflags);
 	
 	_declickable = true;
 	_freeze_record.state = NoFreeze;
@@ -64,6 +65,8 @@ AudioTrack::AudioTrack (Session& sess, string name, Route::Flag flag, TrackMode
 
 	set_diskstream (*ds, this);
 
+	// session.SMPTEOffsetChanged.connect (mem_fun (*this, &AudioTrack::handle_smpte_offset_change));
+
 	// we do this even though Route already did it in it's init
 	reset_midi_control (_session.midi_port(), _session.get_midi_control());
 	
@@ -90,6 +93,14 @@ AudioTrack::~AudioTrack ()
 	}
 }
 
+#if 0
+void
+AudioTrack::handle_smpte_offset_change ()
+{
+	diskstream
+}
+#endif
+
 int
 AudioTrack::deprecated_use_diskstream_connections ()
 {
@@ -143,7 +154,7 @@ AudioTrack::deprecated_use_diskstream_connections ()
 }
 
 int
-AudioTrack::set_diskstream (DiskStream& ds, void *src)
+AudioTrack::set_diskstream (AudioDiskstream& ds, void *src)
 {
 	if (diskstream) {
 		diskstream->unref();
@@ -166,7 +177,7 @@ AudioTrack::set_diskstream (DiskStream& ds, void *src)
 	diskstream->monitor_input (false);
 
 	ic_connection.disconnect();
-	ic_connection = input_changed.connect (mem_fun (*diskstream, &DiskStream::handle_input_change));
+	ic_connection = input_changed.connect (mem_fun (*diskstream, &AudioDiskstream::handle_input_change));
 
 	diskstream_changed (src); /* EMIT SIGNAL */
 
@@ -176,7 +187,7 @@ AudioTrack::set_diskstream (DiskStream& ds, void *src)
 int 
 AudioTrack::use_diskstream (string name)
 {
-	DiskStream *dstream;
+	AudioDiskstream *dstream;
 
 	if ((dstream = _session.diskstream_by_name (name)) == 0) {
 	  error << string_compose(_("AudioTrack: diskstream \"%1\" not known by session"), name) << endmsg;
@@ -189,7 +200,7 @@ AudioTrack::use_diskstream (string name)
 int 
 AudioTrack::use_diskstream (id_t id)
 {
-	DiskStream *dstream;
+	AudioDiskstream *dstream;
 
 	if ((dstream = _session.diskstream_by_id (id)) == 0) {
 	  	error << string_compose(_("AudioTrack: diskstream \"%1\" not known by session"), id) << endmsg;
@@ -899,23 +910,23 @@ AudioTrack::update_total_latency ()
 void
 AudioTrack::bounce (InterThreadInfo& itt)
 {
-	vector<Source*> srcs;
-	_session.write_one_track (*this, 0, _session.current_end_frame(), false, srcs, itt);
+	vector<AudioSource*> srcs;
+	_session.write_one_audio_track (*this, 0, _session.current_end_frame(), false, srcs, itt);
 }
 
 
 void
 AudioTrack::bounce_range (jack_nframes_t start, jack_nframes_t end, InterThreadInfo& itt)
 {
-	vector<Source*> srcs;
-	_session.write_one_track (*this, start, end, false, srcs, itt);
+	vector<AudioSource*> srcs;
+	_session.write_one_audio_track (*this, start, end, false, srcs, itt);
 }
 
 void
 AudioTrack::freeze (InterThreadInfo& itt)
 {
 	Insert* insert;
-	vector<Source*> srcs;
+	vector<AudioSource*> srcs;
 	string new_playlist_name;
 	Playlist* new_playlist;
 	string dir;
@@ -950,7 +961,7 @@ AudioTrack::freeze (InterThreadInfo& itt)
 		return;
 	}
 
-	if (_session.write_one_track (*this, 0, _session.current_end_frame(), true, srcs, itt)) {
+	if (_session.write_one_audio_track (*this, 0, _session.current_end_frame(), true, srcs, itt)) {
 		return;
 	}
 
diff --git a/libs/ardour/audioengine.cc b/libs/ardour/audioengine.cc
index 87866e7b31..c4f90efd49 100644
--- a/libs/ardour/audioengine.cc
+++ b/libs/ardour/audioengine.cc
@@ -229,9 +229,10 @@ AudioEngine::_freewheel_callback (int onoff, void *arg)
 int
 AudioEngine::process_callback (jack_nframes_t nframes)
 {
+	// CycleTimer ct ("AudioEngine::process");
 	Glib::Mutex::Lock tm (_process_lock, Glib::TRY_LOCK);
 	jack_nframes_t next_processed_frames;
-
+	
 	/* handle wrap around of total frames counter */
 
 	if (max_frames - _processed_frames < nframes) {
diff --git a/libs/ardour/audiofilesource.cc b/libs/ardour/audiofilesource.cc
new file mode 100644
index 0000000000..fbddcdafdf
--- /dev/null
+++ b/libs/ardour/audiofilesource.cc
@@ -0,0 +1,661 @@
+/*
+    Copyright (C) 2006 Paul Davis 
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#include <vector>
+
+#include <sys/time.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include <pbd/mountpoint.h>
+#include <pbd/pathscanner.h>
+#include <pbd/stl_delete.h>
+#include <pbd/strsplit.h>
+
+#include <sndfile.h>
+
+#include <glibmm/miscutils.h>
+
+#include <ardour/audiofilesource.h>
+#include <ardour/sndfile_helpers.h>
+#include <ardour/sndfilesource.h>
+#include <ardour/destructive_filesource.h>
+#include <ardour/session.h>
+
+// if these headers come before sigc++ is included
+// the parser throws ObjC++ errors. (nil is a keyword)
+#ifdef HAVE_COREAUDIO 
+#include <ardour/coreaudio_source.h>
+#include <AudioToolbox/ExtendedAudioFile.h>
+#include <AudioToolbox/AudioFormat.h>
+#endif // HAVE_COREAUDIO
+
+#include "i18n.h"
+
+using namespace ARDOUR;
+
+string AudioFileSource::peak_dir = "";
+string AudioFileSource::search_path;
+
+sigc::signal<void,struct tm*, time_t> AudioFileSource::HeaderPositionOffsetChanged;
+bool                                  AudioFileSource::header_position_negative;
+uint64_t                              AudioFileSource::header_position_offset;
+
+char   AudioFileSource::bwf_country_code[3] = "US";
+char   AudioFileSource::bwf_organization_code[4] = "LAS";
+char   AudioFileSource::bwf_serial_number[13] = "000000000000";
+
+AudioFileSource::AudioFileSource (string idstr, Flag flags)
+	: AudioSource (idstr), _flags (flags)
+{
+	/* constructor used for existing external to session files. file must exist already */
+
+	if (init (idstr, true)) {
+		throw failed_constructor ();
+	}
+
+}
+
+AudioFileSource::AudioFileSource (std::string path, Flag flags, SampleFormat samp_format, HeaderFormat hdr_format)
+	: AudioSource (path), _flags (flags)
+{
+	/* constructor used for new internal-to-session files. file cannot exist */
+
+	if (init (path, false)) {
+		throw failed_constructor ();
+	}
+}
+
+AudioFileSource::AudioFileSource (const XMLNode& node)
+	: AudioSource (node), _flags (Flag (Writable|CanRename))
+{
+	/* constructor used for existing internal-to-session files. file must exist */
+
+	if (set_state (node)) {
+		throw failed_constructor ();
+	}
+	
+	if (init (_name, true)) {
+		throw failed_constructor ();
+	}
+}
+
+AudioFileSource::~AudioFileSource ()
+{
+	if (removable()) {
+		unlink (_path.c_str());
+		unlink (peakpath.c_str());
+	}
+}
+
+bool
+AudioFileSource::removable () const
+{
+	return (_flags & Removable) && ((_flags & RemoveAtDestroy) || 
+				      ((_flags & RemovableIfEmpty) && is_empty (_path)));
+}
+
+int
+AudioFileSource::init (string pathstr, bool must_exist)
+{
+	bool is_new = false;
+
+	_length = 0;
+	next_peak_clear_should_notify = false;
+	
+	if (!find (pathstr, must_exist, is_new)) {
+		cerr << "cannot find " << pathstr << " with me = " << must_exist << endl;
+		return -1;
+	}
+
+	if (is_new && must_exist) {
+		return -1;
+	}
+
+	return 0;
+}
+
+
+string
+AudioFileSource::peak_path (string audio_path)
+{
+	return Session::peak_path_from_audio_path (audio_path);
+}
+
+string
+AudioFileSource::old_peak_path (string audio_path)
+{
+	/* XXX hardly bombproof! fix me */
+
+	struct stat stat_file;
+	struct stat stat_mount;
+
+	string mp = mountpoint (audio_path);
+
+	stat (audio_path.c_str(), &stat_file);
+	stat (mp.c_str(), &stat_mount);
+
+	char buf[32];
+#ifdef __APPLE__
+	snprintf (buf, sizeof (buf), "%u-%u-%d.peak", stat_mount.st_ino, stat_file.st_ino, channel);
+#else
+	snprintf (buf, sizeof (buf), "%ld-%ld-%d.peak", stat_mount.st_ino, stat_file.st_ino, channel);
+#endif
+
+	string res = peak_dir;
+	res += buf;
+
+	return res;
+}
+
+#ifdef HAVE_COREAUDIO
+
+AudioFileSource*
+AudioFileSource::create (const XMLNode& node)
+{
+	AudioFileSource* es = 0;
+
+	if (node.property (X_("destructive")) != 0) {
+		
+		es = new DestructiveFileSource (node);
+	
+	} else {
+		
+		try {
+			es = new CoreAudioSource (node);
+		} 
+		
+		
+		catch (failed_constructor& err) {
+			es = new SndFileSource (node);
+		}
+	}
+	
+	return es;
+}
+
+#else
+
+AudioFileSource*
+AudioFileSource::create (const XMLNode& node)
+{
+	if (node.property (X_("destructive")) != 0) {
+		
+		return new DestructiveFileSource (node);
+		
+	} else {
+		
+		return new SndFileSource (node);
+	}
+}
+
+#endif // HAVE_COREAUDIO
+
+#ifdef HAVE_COREAUDIO
+AudioFileSource*
+AudioFileSource::create (const string& idstr)
+{
+	AudioFileSource* es = 0;
+
+	try {
+		es = new CoreAudioSource (idstr);
+	}
+
+	catch (failed_constructor& err) {
+		es = new SndFileSource (idstr);
+	}
+
+	return es;
+}
+
+#else
+
+AudioFileSource*
+AudioFileSource::create (string idstr)
+{
+	return new SndFileSource (idstr);
+}
+
+#endif // HAVE_COREAUDIO
+
+#ifdef HAVE_COREAUDIO
+std::string 
+CFStringRefToStdString(CFStringRef stringRef)
+{
+	CFIndex size = 
+		CFStringGetMaximumSizeForEncoding(CFStringGetLength(stringRef) , 
+		kCFStringEncodingASCII);
+	    char *buf = new char[size];
+	
+	std::string result;
+
+	if(CFStringGetCString(stringRef, buf, size, kCFStringEncodingASCII)) {
+	    result = buf;
+	}
+	delete [] buf;
+	return result;
+}
+#endif // HAVE_COREAUDIO
+
+bool
+AudioFileSource::get_soundfile_info (string path, SoundFileInfo& _info, string& error_msg)
+{
+#ifdef HAVE_COREAUDIO
+	OSStatus err = noErr;
+    FSRef ref; 
+	ExtAudioFileRef af = 0;
+	size_t size;
+    CFStringRef name;
+
+    err = FSPathMakeRef ((UInt8*)path.c_str(), &ref, 0);
+	if (err != noErr) {
+        ExtAudioFileDispose (af);
+		goto libsndfile;
+	}
+
+	err = ExtAudioFileOpen(&ref, &af);
+	if (err != noErr) {
+        ExtAudioFileDispose (af);
+		goto libsndfile;
+	}
+
+	AudioStreamBasicDescription absd;
+	memset(&absd, 0, sizeof(absd));
+	size = sizeof(AudioStreamBasicDescription);
+	err = ExtAudioFileGetProperty(af,
+			kExtAudioFileProperty_FileDataFormat, &size, &absd);
+	if (err != noErr) {
+        ExtAudioFileDispose (af);
+		goto libsndfile;
+	}
+
+	_info.samplerate = absd.mSampleRate;
+	_info.channels   = absd.mChannelsPerFrame;
+
+    size = sizeof(_info.length);
+    err = ExtAudioFileGetProperty(af, kExtAudioFileProperty_FileLengthFrames, &size, &_info.length);
+    if (err != noErr) {
+        ExtAudioFileDispose (af);
+		goto libsndfile;
+    }
+
+	size = sizeof(CFStringRef);
+	err = AudioFormatGetProperty(
+			kAudioFormatProperty_FormatName, sizeof(absd), &absd, &size, &name);
+	if (err != noErr) {
+        ExtAudioFileDispose (af);
+		goto libsndfile;
+	}
+
+	_info.format_name = CFStringRefToStdString(name);
+
+    ExtAudioFileDispose (af);
+	return true;
+	
+libsndfile:
+#endif // HAVE_COREAUDIO
+
+	SNDFILE *sf;
+	SF_INFO sf_info;
+
+	sf_info.format = 0; // libsndfile says to clear this before sf_open().
+
+	if ((sf = sf_open ((char*) path.c_str(), SFM_READ, &sf_info)) == 0) { 
+		char errbuf[256];
+		error_msg = sf_error_str (0, errbuf, sizeof (errbuf) - 1);
+		return false;
+	}
+
+	sf_close (sf);
+
+	_info.samplerate  = sf_info.samplerate;
+	_info.channels    = sf_info.channels;
+	_info.length      = sf_info.frames;
+	_info.format_name = string_compose("Format: %1, %2",
+					   sndfile_major_format(sf_info.format),
+					   sndfile_minor_format(sf_info.format));
+	return true;
+}
+
+XMLNode&
+AudioFileSource::get_state ()
+{
+	XMLNode& root (AudioSource::get_state());
+	char buf[16];
+	snprintf (buf, sizeof (buf), "0x%x", (int)_flags);
+	root.add_property ("flags", buf);
+	return root;
+}
+
+int
+AudioFileSource::set_state (const XMLNode& node)
+{
+	const XMLProperty* prop;
+
+	if (AudioSource::set_state (node)) {
+		return -1;
+	}
+
+	if ((prop = node.property (X_("flags"))) != 0) {
+
+		int ival;
+		sscanf (prop->value().c_str(), "0x%x", &ival);
+		_flags = Flag (ival);
+
+	} else {
+
+		_flags = Flag (0);
+
+	}
+
+	return 0;
+}
+
+void
+AudioFileSource::mark_for_remove ()
+{
+	if (!writable()) {
+		return;
+	}
+	_flags = Flag (_flags | RemoveAtDestroy);
+}
+
+void
+AudioFileSource::mark_streaming_write_completed ()
+{
+	if (!writable()) {
+		return;
+	}
+
+	Glib::Mutex::Lock lm (_lock);
+
+	next_peak_clear_should_notify = true;
+
+	if (_peaks_built || pending_peak_builds.empty()) {
+		_peaks_built = true;
+		 PeaksReady (); /* EMIT SIGNAL */
+	}
+}
+
+void
+AudioFileSource::mark_take (string id)
+{
+	if (writable()) {
+		_take_id = id;
+	}
+}
+
+int
+AudioFileSource::move_to_trash (const string trash_dir_name)
+{
+	string newpath;
+
+	if (!writable()) {
+		return -1;
+	}
+
+	/* don't move the file across filesystems, just
+	   stick it in the `trash_dir_name' directory
+	   on whichever filesystem it was already on.
+	*/
+
+	newpath = Glib::path_get_dirname (_path);
+	newpath = Glib::path_get_dirname (newpath);
+
+	newpath += '/';
+	newpath += trash_dir_name;
+	newpath += '/';
+	newpath += Glib::path_get_basename (_path);
+
+	if (access (newpath.c_str(), F_OK) == 0) {
+
+		/* the new path already exists, try versioning */
+		
+		char buf[PATH_MAX+1];
+		int version = 1;
+		string newpath_v;
+
+		snprintf (buf, sizeof (buf), "%s.%d", newpath.c_str(), version);
+		newpath_v = buf;
+
+		while (access (newpath_v.c_str(), F_OK) == 0 && version < 999) {
+			snprintf (buf, sizeof (buf), "%s.%d", newpath.c_str(), ++version);
+			newpath_v = buf;
+		}
+		
+		if (version == 999) {
+			error << string_compose (_("there are already 1000 files with names like %1; versioning discontinued"),
+					  newpath)
+			      << endmsg;
+		} else {
+			newpath = newpath_v;
+		}
+
+	} else {
+
+		/* it doesn't exist, or we can't read it or something */
+
+	}
+
+	if (::rename (_path.c_str(), newpath.c_str()) != 0) {
+		error << string_compose (_("cannot rename audio file source from %1 to %2 (%3)"),
+				  _path, newpath, strerror (errno))
+		      << endmsg;
+		return -1;
+	}
+
+	if (::unlink (peakpath.c_str()) != 0) {
+		error << string_compose (_("cannot remove peakfile %1 for %2 (%3)"),
+				  peakpath, _path, strerror (errno))
+		      << endmsg;
+		/* try to back out */
+		rename (newpath.c_str(), _path.c_str());
+		return -1;
+	}
+	    
+	_path = newpath;
+	peakpath = "";
+	
+	/* file can not be removed twice, since the operation is not idempotent */
+
+	_flags = Flag (_flags & ~(RemoveAtDestroy|Removable|RemovableIfEmpty));
+
+	return 0;
+}
+
+bool
+AudioFileSource::find (string pathstr, bool must_exist, bool& isnew)
+{
+	string::size_type pos;
+	bool ret = false;
+
+	isnew = false;
+
+	/* clean up PATH:CHANNEL notation so that we are looking for the correct path */
+
+	if ((pos = pathstr.find_last_of (':')) == string::npos) {
+		pathstr = pathstr;
+	} else {
+		pathstr = pathstr.substr (0, pos);
+	}
+
+	if (pathstr[0] != '/') {
+
+		/* non-absolute pathname: find pathstr in search path */
+
+		vector<string> dirs;
+		int cnt;
+		string fullpath;
+		string keeppath;
+
+		if (search_path.length() == 0) {
+			error << _("FileSource: search path not set") << endmsg;
+			goto out;
+		}
+
+		split (search_path, dirs, ':');
+
+		cnt = 0;
+		
+		for (vector<string>::iterator i = dirs.begin(); i != dirs.end(); ++i) {
+
+			fullpath = *i;
+			if (fullpath[fullpath.length()-1] != '/') {
+				fullpath += '/';
+			}
+			fullpath += pathstr;
+			
+			if (access (fullpath.c_str(), R_OK) == 0) {
+				keeppath = fullpath;
+				++cnt;
+			} 
+		}
+
+		if (cnt > 1) {
+
+			error << string_compose (_("FileSource: \"%1\" is ambigous when searching %2\n\t"), pathstr, search_path) << endmsg;
+			goto out;
+
+		} else if (cnt == 0) {
+
+			if (must_exist) {
+				error << string_compose(_("Filesource: cannot find required file (%1): while searching %2"), pathstr, search_path) << endmsg;
+				goto out;
+			} else {
+				isnew = true;
+			}
+		}
+		
+		_name = pathstr;
+		_path = keeppath;
+		ret = true;
+
+	} else {
+		
+		/* external files and/or very very old style sessions include full paths */
+		
+		_path = pathstr;
+		_name = pathstr.substr (pathstr.find_last_of ('/') + 1);
+		
+		if (access (_path.c_str(), R_OK) != 0) {
+
+			/* file does not exist or we cannot read it */
+
+			if (must_exist) {
+				error << string_compose(_("Filesource: cannot find required file (%1): %2"), _path, strerror (errno)) << endmsg;
+				goto out;
+			}
+			
+			if (errno != ENOENT) {
+				error << string_compose(_("Filesource: cannot check for existing file (%1): %2"), _path, strerror (errno)) << endmsg;
+				goto out;
+			}
+			
+			/* a new file */
+
+			isnew = true;
+			ret = true;
+
+		} else {
+			
+			/* already exists */
+
+			ret = true;
+		}
+	}
+	
+  out:
+	return ret;
+}
+
+void
+AudioFileSource::set_search_path (string p)
+{
+	search_path = p;
+}
+
+void
+AudioFileSource::set_header_position_offset (jack_nframes_t offset, bool negative)
+{
+	time_t tnow;
+
+	time (&tnow);
+
+	header_position_offset = offset;
+	header_position_negative = negative;
+	HeaderPositionOffsetChanged (localtime (&tnow), tnow); /* EMIT SIGNAL */
+}
+
+void
+AudioFileSource::set_timeline_position (jack_nframes_t pos)
+{
+	timeline_position = pos;
+}
+
+void
+AudioFileSource::handle_header_position_change (struct tm* now, time_t tnow)
+{
+	/* don't do this if the file has never had its header flushed to disk yet */
+
+	if (writable() && _timestamp) {
+		set_header_timeline_position ();
+		flush_header ();
+	}
+}
+
+void
+AudioFileSource::set_allow_remove_if_empty (bool yn)
+{
+	if (writable()) {
+		allow_remove_if_empty = yn;
+	}
+}
+
+int
+AudioFileSource::set_name (string newname, bool destructive)
+{
+	Glib::Mutex::Lock lm (_lock);
+	string oldpath = _path;
+	string newpath = Session::change_audio_path_by_name (oldpath, _name, newname, destructive);
+
+	if (newpath.empty()) {
+		error << string_compose (_("programming error: %1"), "cannot generate a changed audio path") << endmsg;
+		return -1;
+	}
+
+	if (rename (oldpath.c_str(), newpath.c_str()) != 0) {
+		error << string_compose (_("cannot rename audio file for %1 to %2"), _name, newpath) << endmsg;
+		return -1;
+	}
+
+	_name = Glib::path_get_basename (newpath);
+	_path = newpath;
+
+	return rename_peakfile (peak_path (_path));
+}
+
+bool
+AudioFileSource::is_empty (string path)
+{
+	/* XXX fix me */
+
+	return false;
+}
+
diff --git a/libs/ardour/audiofilter.cc b/libs/ardour/audiofilter.cc
index c340bccb2c..843a3a7d34 100644
--- a/libs/ardour/audiofilter.cc
+++ b/libs/ardour/audiofilter.cc
@@ -22,7 +22,7 @@
 #include <cerrno>
 
 #include <pbd/basename.h>
-#include <ardour/filesource.h>
+#include <ardour/sndfilesource.h>
 #include <ardour/session.h>
 #include <ardour/audioregion.h>
 #include <ardour/audiofilter.h>
@@ -47,7 +47,10 @@ AudioFilter::make_new_sources (AudioRegion& region, AudioRegion::SourceList& nsr
 		}
 
 		try {
-			nsrcs.push_back (new FileSource (path, session.frame_rate(), false, Config->get_native_file_data_format()));
+			nsrcs.push_back (new SndFileSource (path, 
+							    Config->get_native_file_data_format(),
+							    Config->get_native_file_header_format(),
+							    session.frame_rate()));
 		} 
 
 		catch (failed_constructor& err) {
@@ -73,7 +76,10 @@ AudioFilter::finish (AudioRegion& region, AudioRegion::SourceList& nsrcs)
 	now = localtime (&xnow);
 
 	for (AudioRegion::SourceList::iterator si = nsrcs.begin(); si != nsrcs.end(); ++si) {
-		dynamic_cast<FileSource*>((*si))->update_header (region.position(), *now, xnow);
+		AudioFileSource* afs = dynamic_cast<AudioFileSource*>(*si);
+		if (afs) {
+			afs->update_header (region.position(), *now, xnow);
+		}
 	}
 
 	/* create a new region */
diff --git a/libs/ardour/audioregion.cc b/libs/ardour/audioregion.cc
index 21773d9222..6b118faa51 100644
--- a/libs/ardour/audioregion.cc
+++ b/libs/ardour/audioregion.cc
@@ -38,6 +38,7 @@
 #include <ardour/dB.h>
 #include <ardour/playlist.h>
 #include <ardour/audiofilter.h>
+#include <ardour/audiosource.h>
 
 #include "i18n.h"
 #include <locale.h>
@@ -63,7 +64,7 @@ AudioRegionState::AudioRegionState (string why)
 {
 }
 
-AudioRegion::AudioRegion (Source& src, jack_nframes_t start, jack_nframes_t length, bool announce)
+AudioRegion::AudioRegion (AudioSource& src, jack_nframes_t start, jack_nframes_t length, bool announce)
 	: Region (start, length, PBD::basename_nosuffix(src.name()), 0,  Region::Flag(Region::DefaultFlags|Region::External)),
 	  _fade_in (0.0, 2.0, 1.0, false),
 	  _fade_out (0.0, 2.0, 1.0, false),
@@ -89,7 +90,7 @@ AudioRegion::AudioRegion (Source& src, jack_nframes_t start, jack_nframes_t leng
 	}
 }
 
-AudioRegion::AudioRegion (Source& src, jack_nframes_t start, jack_nframes_t length, const string& name, layer_t layer, Flag flags, bool announce)
+AudioRegion::AudioRegion (AudioSource& src, jack_nframes_t start, jack_nframes_t length, const string& name, layer_t layer, Flag flags, bool announce)
 	: Region (start, length, name, layer, flags),
 	  _fade_in (0.0, 2.0, 1.0, false),
 	  _fade_out (0.0, 2.0, 1.0, false),
@@ -150,7 +151,7 @@ AudioRegion::AudioRegion (const AudioRegion& other, jack_nframes_t offset, jack_
 {
 	/* create a new AudioRegion, that is part of an existing one */
 	
-	set<Source*> unique_srcs;
+	set<AudioSource*> unique_srcs;
 
 	for (SourceList::const_iterator i= other.sources.begin(); i != other.sources.end(); ++i) {
 		sources.push_back (*i);
@@ -209,7 +210,7 @@ AudioRegion::AudioRegion (const AudioRegion &other)
 {
 	/* Pure copy constructor */
 
-	set<Source*> unique_srcs;
+	set<AudioSource*> unique_srcs;
 
 	for (SourceList::const_iterator i = other.sources.begin(); i != other.sources.end(); ++i) {
 		sources.push_back (*i);
@@ -237,7 +238,7 @@ AudioRegion::AudioRegion (const AudioRegion &other)
 	/* NOTE: no CheckNewRegion signal emitted here. This is the copy constructor */
 }
 
-AudioRegion::AudioRegion (Source& src, const XMLNode& node)
+AudioRegion::AudioRegion (AudioSource& src, const XMLNode& node)
 	: Region (node),
 	  _fade_in (0.0, 2.0, 1.0, false),
 	  _fade_out (0.0, 2.0, 1.0, false),
@@ -268,7 +269,7 @@ AudioRegion::AudioRegion (SourceList& srcs, const XMLNode& node)
 {
 	/* basic AudioRegion constructor */
 
-	set<Source*> unique_srcs;
+	set<AudioSource*> unique_srcs;
 
 	for (SourceList::iterator i=srcs.begin(); i != srcs.end(); ++i) {
 		sources.push_back (*i);
@@ -1094,7 +1095,7 @@ void
 AudioRegion::lock_sources ()
 {
 	SourceList::iterator i;
-	set<Source*> unique_srcs;
+	set<AudioSource*> unique_srcs;
 
 	for (i = sources.begin(); i != sources.end(); ++i) {
 		unique_srcs.insert (*i);
@@ -1112,7 +1113,7 @@ void
 AudioRegion::unlock_sources ()
 {
 	SourceList::iterator i;
-	set<Source*> unique_srcs;
+	set<AudioSource*> unique_srcs;
 
 	for (i = sources.begin(); i != sources.end(); ++i) {
 		unique_srcs.insert (*i);
diff --git a/libs/ardour/audiosource.cc b/libs/ardour/audiosource.cc
new file mode 100644
index 0000000000..46596ad64f
--- /dev/null
+++ b/libs/ardour/audiosource.cc
@@ -0,0 +1,897 @@
+/*
+    Copyright (C) 2000 Paul Davis 
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+    $Id: source.cc 404 2006-03-17 17:39:21Z pauld $
+*/
+
+#include <sys/stat.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <poll.h>
+#include <float.h>
+#include <cerrno>
+#include <ctime>
+#include <cmath>
+#include <iomanip>
+#include <algorithm>
+
+#include <pbd/xml++.h>
+#include <pbd/pthread_utils.h>
+
+#include <ardour/audiosource.h>
+
+#include "i18n.h"
+
+using namespace std;
+using namespace ARDOUR;
+using namespace PBD;
+
+sigc::signal<void,AudioSource *> AudioSource::AudioSourceCreated;
+pthread_t                    AudioSource::peak_thread;
+bool                         AudioSource::have_peak_thread = false;
+vector<AudioSource*>         AudioSource::pending_peak_sources;
+Glib::Mutex*                 AudioSource::pending_peak_sources_lock = 0;
+int                          AudioSource::peak_request_pipe[2];
+
+bool AudioSource::_build_missing_peakfiles = false;
+bool AudioSource::_build_peakfiles = false;
+
+AudioSource::AudioSource (string name)
+	: Source (name)
+{
+	if (pending_peak_sources_lock == 0) {
+		pending_peak_sources_lock = new Glib::Mutex;
+	}
+
+	_peaks_built = false;
+	next_peak_clear_should_notify = true;
+	_read_data_count = 0;
+	_write_data_count = 0;
+}
+
+AudioSource::AudioSource (const XMLNode& node) 
+	: Source (node)
+{
+	if (pending_peak_sources_lock == 0) {
+		pending_peak_sources_lock = new Glib::Mutex;
+	}
+
+	_peaks_built = false;
+	next_peak_clear_should_notify = true;
+	_read_data_count = 0;
+	_write_data_count = 0;
+
+	if (set_state (node)) {
+		throw failed_constructor();
+	}
+}
+
+AudioSource::~AudioSource ()
+{
+}
+
+XMLNode&
+AudioSource::get_state ()
+{
+	XMLNode& node (Source::get_state());
+
+	if (_captured_for.length()) {
+		node.add_property ("captured-for", _captured_for);
+	}
+
+	return node;
+}
+
+int
+AudioSource::set_state (const XMLNode& node)
+{
+	const XMLProperty* prop;
+
+	Source::set_state (node);
+
+	if ((prop = node.property ("captured-for")) != 0) {
+		_captured_for = prop->value();
+	}
+
+	return 0;
+}
+
+/***********************************************************************
+  PEAK FILE STUFF
+ ***********************************************************************/
+
+void*
+AudioSource::peak_thread_work (void* arg)
+{
+	PBD::ThreadCreated (pthread_self(), X_("Peak"));
+	struct pollfd pfd[1];
+
+	if (pending_peak_sources_lock == 0) {
+		pending_peak_sources_lock = new Glib::Mutex;
+	}
+
+	Glib::Mutex::Lock lm (*pending_peak_sources_lock);
+
+	while (true) {
+
+		pfd[0].fd = peak_request_pipe[0];
+		pfd[0].events = POLLIN|POLLERR|POLLHUP;
+
+		pending_peak_sources_lock->unlock ();
+
+		if (poll (pfd, 1, -1) < 0) {
+
+			if (errno == EINTR) {
+				pending_peak_sources_lock->lock ();
+				continue;
+			}
+			
+			error << string_compose (_("poll on peak request pipe failed (%1)"),
+					  strerror (errno))
+			      << endmsg;
+			break;
+		}
+
+		if (pfd[0].revents & ~POLLIN) {
+			error << _("Error on peak thread request pipe") << endmsg;
+			break;
+		}
+
+		if (pfd[0].revents & POLLIN) {
+
+			char req;
+			
+			/* empty the pipe of all current requests */
+
+			while (1) {
+				size_t nread = ::read (peak_request_pipe[0], &req, sizeof (req));
+
+				if (nread == 1) {
+					switch ((PeakRequest::Type) req) {
+					
+					case PeakRequest::Build:
+						break;
+						
+					case PeakRequest::Quit:
+						pthread_exit_pbd (0);
+						/*NOTREACHED*/
+						break;
+						
+					default:
+						break;
+					}
+
+				} else if (nread == 0) {
+					break;
+				} else if (errno == EAGAIN) {
+					break;
+				} else {
+					fatal << _("Error reading from peak request pipe") << endmsg;
+					/*NOTREACHED*/
+				}
+			}
+		}
+
+		pending_peak_sources_lock->lock ();
+
+		while (!pending_peak_sources.empty()) {
+
+			AudioSource* s = pending_peak_sources.front();
+			pending_peak_sources.erase (pending_peak_sources.begin());
+			
+			pending_peak_sources_lock->unlock ();
+			s->build_peaks();
+			pending_peak_sources_lock->lock ();
+		}
+	}
+
+	pthread_exit_pbd (0);
+	/*NOTREACHED*/
+	return 0;
+}
+
+int
+AudioSource::start_peak_thread ()
+{
+	if (!_build_peakfiles) {
+		return 0;
+	}
+
+	if (pipe (peak_request_pipe)) {
+		error << string_compose(_("Cannot create transport request signal pipe (%1)"), strerror (errno)) << endmsg;
+		return -1;
+	}
+
+	if (fcntl (peak_request_pipe[0], F_SETFL, O_NONBLOCK)) {
+		error << string_compose(_("UI: cannot set O_NONBLOCK on peak request pipe (%1)"), strerror (errno)) << endmsg;
+		return -1;
+	}
+
+	if (fcntl (peak_request_pipe[1], F_SETFL, O_NONBLOCK)) {
+		error << string_compose(_("UI: cannot set O_NONBLOCK on peak request pipe (%1)"), strerror (errno)) << endmsg;
+		return -1;
+	}
+
+	if (pthread_create_and_store ("peak file builder", &peak_thread, 0, peak_thread_work, 0)) {
+		error << _("AudioSource: could not create peak thread") << endmsg;
+		return -1;
+	}
+
+	have_peak_thread = true;
+	return 0;
+}
+
+void
+AudioSource::stop_peak_thread ()
+{
+	if (!have_peak_thread) {
+		return;
+	}
+
+	void* status;
+
+	char c = (char) PeakRequest::Quit;
+	::write (peak_request_pipe[1], &c, 1);
+	pthread_join (peak_thread, &status);
+}
+
+void 
+AudioSource::queue_for_peaks (AudioSource& source)
+{
+	if (have_peak_thread) {
+
+		Glib::Mutex::Lock lm (*pending_peak_sources_lock);
+		
+		source.next_peak_clear_should_notify = true;
+		
+		if (find (pending_peak_sources.begin(),
+			  pending_peak_sources.end(),
+			  &source) == pending_peak_sources.end()) {
+			pending_peak_sources.push_back (&source);
+		}
+
+		char c = (char) PeakRequest::Build;
+		::write (peak_request_pipe[1], &c, 1);
+	}
+}
+
+void AudioSource::clear_queue_for_peaks ()
+{
+	/* this is done to cancel a group of running peak builds */
+	if (have_peak_thread) {
+		Glib::Mutex::Lock lm (*pending_peak_sources_lock);
+		pending_peak_sources.clear ();
+	}
+}
+
+
+bool
+AudioSource::peaks_ready (sigc::slot<void> the_slot, sigc::connection& conn) const
+{
+	bool ret;
+	Glib::Mutex::Lock lm (_lock);
+
+	/* check to see if the peak data is ready. if not
+	   connect the slot while still holding the lock.
+	*/
+
+	if (!(ret = _peaks_built)) {
+		conn = PeaksReady.connect (the_slot);
+	}
+
+	return ret;
+}
+
+int
+AudioSource::rename_peakfile (string newpath)
+{
+	/* caller must hold _lock */
+
+	string oldpath = peakpath;
+
+	if (access (oldpath.c_str(), F_OK) == 0) {
+		if (rename (oldpath.c_str(), newpath.c_str()) != 0) {
+			error << string_compose (_("cannot rename peakfile for %1 from %2 to %3 (%4)"), _name, oldpath, newpath, strerror (errno)) << endmsg;
+			return -1;
+		}
+	}
+
+	peakpath = newpath;
+
+	return 0;
+}
+
+int
+AudioSource::initialize_peakfile (bool newfile, string audio_path)
+{
+	struct stat statbuf;
+
+	peakpath = peak_path (audio_path);
+
+	/* Nasty band-aid for older sessions that were created before we
+	   used libsndfile for all audio files.
+	*/
+	
+	if (!newfile && access (peakpath.c_str(), R_OK) != 0) {
+		string str = old_peak_path (audio_path);
+		if (access (str.c_str(), R_OK) == 0) {
+			peakpath = str;
+		}
+	}
+
+	if (newfile) {
+
+		if (!_build_peakfiles) {
+			return 0;
+		}
+
+		_peaks_built = false;
+
+	} else {
+
+		if (stat (peakpath.c_str(), &statbuf)) {
+			if (errno != ENOENT) {
+				/* it exists in the peaks dir, but there is some kind of error */
+				
+				error << string_compose(_("AudioSource: cannot stat peakfile \"%1\""), peakpath) << endmsg;
+				return -1;
+			}
+
+		} else {
+			
+			/* we found it in the peaks dir */
+		}
+		
+		if (statbuf.st_size == 0) {
+			_peaks_built = false;
+		} else {
+			// Check if the audio file has changed since the peakfile was built.
+			struct stat stat_file;
+			int err = stat (audio_path.c_str(), &stat_file);
+			
+			if (!err && stat_file.st_mtime > statbuf.st_mtime){
+				_peaks_built = false;
+			} else {
+				_peaks_built = true;
+			}
+		}
+	}
+
+	if (!newfile && !_peaks_built && _build_missing_peakfiles && _build_peakfiles) {
+		build_peaks_from_scratch ();
+	} 
+
+	return 0;
+}
+
+jack_nframes_t
+AudioSource::read (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const
+{
+	Glib::Mutex::Lock lm (_lock);
+	return read_unlocked (dst, start, cnt, workbuf);
+}
+
+jack_nframes_t
+AudioSource::write (Sample *dst, jack_nframes_t cnt, char * workbuf)
+{
+	Glib::Mutex::Lock lm (_lock);
+	return write_unlocked (dst, cnt, workbuf);
+}
+
+int 
+AudioSource::read_peaks (PeakData *peaks, jack_nframes_t npeaks, jack_nframes_t start, jack_nframes_t cnt, double samples_per_visual_peak) const
+{
+	Glib::Mutex::Lock lm (_lock);
+	double scale;
+	double expected_peaks;
+	PeakData::PeakDatum xmax;
+	PeakData::PeakDatum xmin;
+	int32_t to_read;
+	uint32_t nread;
+	jack_nframes_t zero_fill = 0;
+	int ret = -1;
+	PeakData* staging = 0;
+	Sample* raw_staging = 0;
+	char * workbuf = 0;
+	int peakfile = -1;
+
+	expected_peaks = (cnt / (double) frames_per_peak);
+	scale = npeaks/expected_peaks;
+
+#if 0
+	cerr << "======>RP: npeaks = " << npeaks 
+	     << " start = " << start 
+	     << " cnt = " << cnt 
+	     << " len = " << _length 
+	     << "   samples_per_visual_peak =" << samples_per_visual_peak 
+	     << " expected was " << expected_peaks << " ... scale = " << scale
+	     << " PD ptr = " << peaks
+	     <<endl;
+	
+#endif
+
+	/* fix for near-end-of-file conditions */
+
+	if (cnt > _length - start) {
+		// cerr << "too close to end @ " << _length << " given " << start << " + " << cnt << endl;
+		cnt = _length - start;
+		jack_nframes_t old = npeaks;
+		npeaks = min ((jack_nframes_t) floor (cnt / samples_per_visual_peak), npeaks);
+		zero_fill = old - npeaks;
+	}
+
+	// cerr << "actual npeaks = " << npeaks << " zf = " << zero_fill << endl;
+	
+	if (npeaks == cnt) {
+
+		// cerr << "RAW DATA\n";
+		
+		/* no scaling at all, just get the sample data and duplicate it for
+		   both max and min peak values.
+		*/
+
+		Sample* raw_staging = new Sample[cnt];
+		workbuf = new char[cnt*4];
+		
+		if (read_unlocked (raw_staging, start, cnt, workbuf) != cnt) {
+			error << _("cannot read sample data for unscaled peak computation") << endmsg;
+			return -1;
+		}
+
+		for (jack_nframes_t i = 0; i < npeaks; ++i) {
+			peaks[i].max = raw_staging[i];
+			peaks[i].min = raw_staging[i];
+		}
+
+		delete [] raw_staging;
+		delete [] workbuf;
+		return 0;
+	}
+
+	if (scale == 1.0) {
+
+		off_t first_peak_byte = (start / frames_per_peak) * sizeof (PeakData);
+
+		/* open, read, close */
+
+		if ((peakfile = ::open (peakpath.c_str(), O_RDWR|O_CREAT, 0664)) < 0) {
+			error << string_compose(_("AudioSource: cannot open peakpath \"%1\" (%2)"), peakpath, strerror (errno)) << endmsg;
+			return -1;
+		}
+
+		// cerr << "DIRECT PEAKS\n";
+		
+		nread = ::pread (peakfile, peaks, sizeof (PeakData)* npeaks, first_peak_byte);
+		close (peakfile);
+
+		if (nread != sizeof (PeakData) * npeaks) {
+			cerr << "AudioSource["
+			     << _name
+			     << "]: cannot read peaks from peakfile! (read only " 
+			     << nread
+			     << " not " 
+			     << npeaks
+			      << "at sample " 
+			     << start
+			     << " = byte "
+			     << first_peak_byte
+			     << ')'
+			     << endl;
+			return -1;
+		}
+
+		if (zero_fill) {
+			memset (&peaks[npeaks], 0, sizeof (PeakData) * zero_fill);
+		}
+
+		return 0;
+	}
+
+
+	jack_nframes_t tnp;
+
+	if (scale < 1.0) {
+
+		// cerr << "DOWNSAMPLE\n";
+
+		/* the caller wants:
+
+		    - more frames-per-peak (lower resolution) than the peakfile, or to put it another way,
+                    - less peaks than the peakfile holds for the same range
+
+		    So, read a block into a staging area, and then downsample from there.
+
+		    to avoid confusion, I'll refer to the requested peaks as visual_peaks and the peakfile peaks as stored_peaks  
+		*/
+
+		const uint32_t chunksize = (uint32_t) min (expected_peaks, 4096.0);
+		
+		staging = new PeakData[chunksize];
+		
+		/* compute the rounded up frame position  */
+	
+		jack_nframes_t current_frame = start;
+		jack_nframes_t current_stored_peak = (jack_nframes_t) ceil (current_frame / (double) frames_per_peak);
+		uint32_t       next_visual_peak  = (uint32_t) ceil (current_frame / samples_per_visual_peak);
+		double         next_visual_peak_frame = next_visual_peak * samples_per_visual_peak;
+		uint32_t       stored_peak_before_next_visual_peak = (jack_nframes_t) next_visual_peak_frame / frames_per_peak;
+		uint32_t       nvisual_peaks = 0;
+		uint32_t       stored_peaks_read = 0;
+		uint32_t       i = 0;
+
+		/* handle the case where the initial visual peak is on a pixel boundary */
+
+		current_stored_peak = min (current_stored_peak, stored_peak_before_next_visual_peak);
+
+		/* open ... close during out: handling */
+
+		if ((peakfile = ::open (peakpath.c_str(), O_RDWR|O_CREAT, 0664)) < 0) {
+			error << string_compose(_("AudioSource: cannot open peakpath \"%1\" (%2)"), peakpath, strerror (errno)) << endmsg;
+			return 0;
+		}
+
+		while (nvisual_peaks < npeaks) {
+
+			if (i == stored_peaks_read) {
+
+				uint32_t       start_byte = current_stored_peak * sizeof(PeakData);
+				tnp = min ((_length/frames_per_peak - current_stored_peak), (jack_nframes_t) expected_peaks);
+				to_read = min (chunksize, tnp);
+				
+				off_t fend = lseek (peakfile, 0, SEEK_END);
+				
+				if ((nread = ::pread (peakfile, staging, sizeof (PeakData) * to_read, start_byte))
+				    != sizeof (PeakData) * to_read) {
+					cerr << "AudioSource["
+					     << _name
+					     << "]: cannot read peak data from peakfile ("
+					     << (nread / sizeof(PeakData))
+					     << " peaks instead of "
+					     << to_read
+					     << ") ("
+					     << strerror (errno)
+					     << ')'
+					     << " at start_byte = " << start_byte 
+					     << " _length = " << _length << " versus len = " << fend
+					     << " expected maxpeaks = " << (_length - current_frame)/frames_per_peak
+					     << " npeaks was " << npeaks
+					     << endl;
+					goto out;
+				}
+
+				i = 0;
+				stored_peaks_read = nread / sizeof(PeakData);
+			}
+
+			xmax = -1.0;
+			xmin = 1.0;
+
+			while ((i < stored_peaks_read) && (current_stored_peak <= stored_peak_before_next_visual_peak)) {
+
+				xmax = max (xmax, staging[i].max);
+				xmin = min (xmin, staging[i].min);
+				++i;
+				++current_stored_peak;
+				--expected_peaks;
+			}
+
+			peaks[nvisual_peaks].max = xmax;
+			peaks[nvisual_peaks].min = xmin;
+			++nvisual_peaks;
+			++next_visual_peak;
+
+			//next_visual_peak_frame = min ((next_visual_peak * samples_per_visual_peak), (next_visual_peak_frame+samples_per_visual_peak) );
+			next_visual_peak_frame =  min ((double) start+cnt, (next_visual_peak_frame+samples_per_visual_peak) );
+			stored_peak_before_next_visual_peak = (uint32_t) next_visual_peak_frame / frames_per_peak; 
+		}
+
+		if (zero_fill) {
+ 			memset (&peaks[npeaks], 0, sizeof (PeakData) * zero_fill);
+ 		}
+		
+		ret = 0;
+
+	} else {
+		
+		// cerr << "UPSAMPLE\n";
+
+		/* the caller wants 
+
+		     - less frames-per-peak (more resolution)
+		     - more peaks than stored in the Peakfile
+
+		   So, fetch data from the raw source, and generate peak
+		   data on the fly.
+		*/
+
+		jack_nframes_t frames_read = 0;
+		jack_nframes_t current_frame = start;
+		jack_nframes_t i = 0;
+		jack_nframes_t nvisual_peaks = 0;
+		jack_nframes_t chunksize = (jack_nframes_t) min (cnt, (jack_nframes_t) 4096);
+		raw_staging = new Sample[chunksize];
+		workbuf = new char[chunksize *4];
+		
+		jack_nframes_t frame_pos = start;
+		double pixel_pos = floor (frame_pos / samples_per_visual_peak);
+		double next_pixel_pos = ceil (frame_pos / samples_per_visual_peak);
+		double pixels_per_frame = 1.0 / samples_per_visual_peak;
+
+		xmin = 1.0;
+		xmax = -1.0;
+
+		while (nvisual_peaks < npeaks) {
+
+			if (i == frames_read) {
+				
+				to_read = min (chunksize, (_length - current_frame));
+				
+				if ((frames_read = read_unlocked (raw_staging, current_frame, to_read, workbuf)) < 0) {
+					error << string_compose(_("AudioSource[%1]: peak read - cannot read %2 samples at offset %3")
+							 , _name, to_read, current_frame) 
+					      << endmsg;
+					goto out;
+				}
+
+				i = 0;
+			}
+			
+			xmax = max (xmax, raw_staging[i]);
+			xmin = min (xmin, raw_staging[i]);
+			++i;
+			++current_frame;
+			pixel_pos += pixels_per_frame;
+
+			if (pixel_pos >= next_pixel_pos) {
+
+				peaks[nvisual_peaks].max = xmax;
+				peaks[nvisual_peaks].min = xmin;
+				++nvisual_peaks;
+				xmin = 1.0;
+				xmax = -1.0;
+
+				next_pixel_pos = ceil (pixel_pos + 0.5);
+			}
+		}
+		
+		if (zero_fill) {
+			memset (&peaks[npeaks], 0, sizeof (PeakData) * zero_fill);
+		}
+
+		ret = 0;
+	}
+
+  out:
+	if (peakfile >= 0) {
+		close (peakfile);
+	}
+
+	if (staging) {
+		delete [] staging;
+	} 
+
+	if (raw_staging) {
+		delete [] raw_staging;
+	}
+
+	if (workbuf) {
+		delete [] workbuf;
+	}
+	
+	return ret;
+}
+
+#undef DEBUG_PEAK_BUILD
+
+int
+AudioSource::build_peaks ()
+{
+	vector<PeakBuildRecord*> built;
+	int status = -1;
+	bool pr_signal = false;
+	list<PeakBuildRecord*> copy;
+
+	{
+		Glib::Mutex::Lock lm (_lock);
+		copy = pending_peak_builds;
+		pending_peak_builds.clear ();
+	}
+		
+#ifdef DEBUG_PEAK_BUILD
+	cerr << "build peaks with " << copy.size() << " requests pending\n";
+#endif		
+
+	for (list<PeakBuildRecord *>::iterator i = copy.begin(); i != copy.end(); ++i) {
+		
+		if ((status = do_build_peak ((*i)->frame, (*i)->cnt)) != 0) { 
+			unlink (peakpath.c_str());
+			break;
+		}
+		built.push_back (new PeakBuildRecord (*(*i)));
+		delete *i;
+	}
+
+	{ 
+		Glib::Mutex::Lock lm (_lock);
+
+		if (status == 0) {
+			_peaks_built = true;
+			
+			if (next_peak_clear_should_notify) {
+				next_peak_clear_should_notify = false;
+				pr_signal = true;
+			}
+		}
+	}
+
+	if (status == 0) {
+		for (vector<PeakBuildRecord *>::iterator i = built.begin(); i != built.end(); ++i) {
+			PeakRangeReady ((*i)->frame, (*i)->cnt); /* EMIT SIGNAL */
+			delete *i;
+		}
+
+		if (pr_signal) {
+			PeaksReady (); /* EMIT SIGNAL */
+		}
+	}
+
+	return status;
+}
+
+int
+AudioSource::do_build_peak (jack_nframes_t first_frame, jack_nframes_t cnt)
+{
+	jack_nframes_t current_frame;
+	Sample buf[frames_per_peak];
+	Sample xmin, xmax;
+	uint32_t  peaki;
+	PeakData* peakbuf;
+	char * workbuf = 0;
+	jack_nframes_t frames_read;
+	jack_nframes_t frames_to_read;
+	off_t first_peak_byte;
+	int peakfile = -1;
+	int ret = -1;
+
+#ifdef DEBUG_PEAK_BUILD
+	cerr << pthread_self() << ": " << _name << ": building peaks for " << first_frame << " to " << first_frame + cnt - 1 << endl;
+#endif
+
+	first_peak_byte = (first_frame / frames_per_peak) * sizeof (PeakData);
+
+#ifdef DEBUG_PEAK_BUILD
+	cerr << "seeking to " << first_peak_byte << " before writing new peak data\n";
+#endif
+
+	current_frame = first_frame;
+	peakbuf = new PeakData[(cnt/frames_per_peak)+1];
+	peaki = 0;
+
+	workbuf = new char[max(frames_per_peak, cnt) * 4];
+	
+	if ((peakfile = ::open (peakpath.c_str(), O_RDWR|O_CREAT, 0664)) < 0) {
+		error << string_compose(_("AudioSource: cannot open peakpath \"%1\" (%2)"), peakpath, strerror (errno)) << endmsg;
+		return -1;
+	}
+	
+	while (cnt) {
+
+		frames_to_read = min (frames_per_peak, cnt);
+
+		if ((frames_read = read_unlocked (buf, current_frame, frames_to_read, workbuf)) != frames_to_read) {
+			error << string_compose(_("%1: could not write read raw data for peak computation (%2)"), _name, strerror (errno)) << endmsg;
+			goto out;
+		}
+
+		xmin = buf[0];
+		xmax = buf[0];
+
+		for (jack_nframes_t n = 1; n < frames_read; ++n) {
+			xmax = max (xmax, buf[n]);
+			xmin = min (xmin, buf[n]);
+
+//			if (current_frame < frames_read) {
+//				cerr << "sample = " << buf[n] << " max = " << xmax << " min = " << xmin << " max of 2 = " << max (xmax, buf[n]) << endl;
+//			}
+		}
+
+		peakbuf[peaki].max = xmax;
+		peakbuf[peaki].min = xmin;
+		peaki++;
+
+		current_frame += frames_read;
+		cnt -= frames_read;
+	}
+
+	if (::pwrite (peakfile, peakbuf, sizeof (PeakData) * peaki, first_peak_byte) != (ssize_t) (sizeof (PeakData) * peaki)) {
+		error << string_compose(_("%1: could not write peak file data (%2)"), _name, strerror (errno)) << endmsg;
+		goto out;
+	}
+
+	ret = 0;
+
+  out:
+	delete [] peakbuf;
+	if (peakfile >= 0) {
+		close (peakfile);
+	}
+	if (workbuf)
+		delete [] workbuf;
+	return ret;
+}
+
+void
+AudioSource::build_peaks_from_scratch ()
+{
+	Glib::Mutex::Lock lp (_lock);
+
+	next_peak_clear_should_notify = true;
+	pending_peak_builds.push_back (new PeakBuildRecord (0, _length));
+	queue_for_peaks (*this);
+}
+
+bool
+AudioSource::file_changed (string path)
+{
+	struct stat stat_file;
+	struct stat stat_peak;
+
+	int e1 = stat (path.c_str(), &stat_file);
+	int e2 = stat (peak_path(path).c_str(), &stat_peak);
+	
+	if (!e1 && !e2 && stat_file.st_mtime > stat_peak.st_mtime){
+		return true;
+	} else {
+		return false;
+	}
+}
+
+jack_nframes_t
+AudioSource::available_peaks (double zoom_factor) const
+{
+	int peakfile;
+	off_t end;
+
+	if (zoom_factor < frames_per_peak) {
+		return length(); // peak data will come from the audio file
+	} 
+	
+	/* peak data comes from peakfile */
+
+	if ((peakfile = ::open (peakpath.c_str(), O_RDONLY)) < 0) {
+		error << string_compose(_("AudioSource: cannot open peakpath \"%1\" (%2)"), peakpath, strerror (errno)) << endmsg;
+		return 0;
+	}
+
+	{ 
+		Glib::Mutex::Lock lm (_lock);
+		end = lseek (peakfile, 0, SEEK_END);
+	}
+
+	close (peakfile);
+
+	return (end/sizeof(PeakData)) * frames_per_peak;
+}
+
+void
+AudioSource::update_length (jack_nframes_t pos, jack_nframes_t cnt)
+{
+	if (pos + cnt > _length) {
+		_length = pos+cnt;
+	}
+}
+
diff --git a/libs/ardour/auditioner.cc b/libs/ardour/auditioner.cc
index ce7b9a3e6f..2f0b943c0e 100644
--- a/libs/ardour/auditioner.cc
+++ b/libs/ardour/auditioner.cc
@@ -20,7 +20,7 @@
 
 #include <glibmm/thread.h>
 
-#include <ardour/diskstream.h>
+#include <ardour/audio_diskstream.h>
 #include <ardour/audioregion.h>
 #include <ardour/route.h>
 #include <ardour/session.h>
diff --git a/libs/ardour/configuration.cc b/libs/ardour/configuration.cc
index b7b1d65815..e73208b872 100644
--- a/libs/ardour/configuration.cc
+++ b/libs/ardour/configuration.cc
@@ -26,7 +26,7 @@
 
 #include <ardour/ardour.h>
 #include <ardour/configuration.h>
-#include <ardour/diskstream.h>
+#include <ardour/audio_diskstream.h>
 #include <ardour/destructive_filesource.h>
 #include <ardour/control_protocol_manager.h>
 
@@ -231,7 +231,7 @@ Configuration::set_state (const XMLNode& root)
 		}
 	}
 
-	DiskStream::set_disk_io_chunk_frames (minimum_disk_io_bytes.get() / sizeof (Sample));
+	AudioDiskstream::set_disk_io_chunk_frames (minimum_disk_io_bytes.get() / sizeof (Sample));
 
 	return 0;
 }
diff --git a/libs/ardour/destructive_filesource.cc b/libs/ardour/destructive_filesource.cc
index 9a4c2425e9..00fabba445 100644
--- a/libs/ardour/destructive_filesource.cc
+++ b/libs/ardour/destructive_filesource.cc
@@ -66,13 +66,9 @@ gain_t* DestructiveFileSource::out_coefficient = 0;
 gain_t* DestructiveFileSource::in_coefficient = 0;
 jack_nframes_t DestructiveFileSource::xfade_frames = 64;
 
-DestructiveFileSource::DestructiveFileSource (string path, jack_nframes_t rate, bool repair_first, SampleFormat samp_format)
-	: FileSource (path, rate, repair_first, samp_format)
+DestructiveFileSource::DestructiveFileSource (string path, SampleFormat samp_format, HeaderFormat hdr_format, jack_nframes_t rate, Flag flags)
+	: SndFileSource (path, samp_format, hdr_format, rate, flags)
 {
-	if (out_coefficient == 0) {
-		setup_standard_crossfades (rate);
-	}
-
 	xfade_buf = new Sample[xfade_frames];
 
 	_capture_start = false;
@@ -80,13 +76,9 @@ DestructiveFileSource::DestructiveFileSource (string path, jack_nframes_t rate,
 	file_pos = 0;
 }
 
-DestructiveFileSource::DestructiveFileSource (const XMLNode& node, jack_nframes_t rate)
-	: FileSource (node, rate)
+DestructiveFileSource::DestructiveFileSource (const XMLNode& node)
+	: SndFileSource (node)
 {
-	if (out_coefficient == 0) {
-		setup_standard_crossfades (rate);
-	}
-
 	xfade_buf = new Sample[xfade_frames];
 
 	_capture_start = false;
@@ -102,6 +94,10 @@ DestructiveFileSource::~DestructiveFileSource()
 void
 DestructiveFileSource::setup_standard_crossfades (jack_nframes_t rate)
 {
+	/* This static method is assumed to have been called by the Session
+	   before any DFS's are created.
+	*/
+
 	xfade_frames = (jack_nframes_t) floor ((Config->get_destructive_xfade_msecs () / 1000.0) * rate);
 
 	if (out_coefficient) {
@@ -124,12 +120,6 @@ DestructiveFileSource::setup_standard_crossfades (jack_nframes_t rate)
 	}
 }
 
-int
-DestructiveFileSource::seek (jack_nframes_t frame)
-{
-	return 0;
-}
-
 void
 DestructiveFileSource::mark_capture_start (jack_nframes_t pos)
 {
@@ -188,7 +178,7 @@ DestructiveFileSource::crossfade (Sample* data, jack_nframes_t cnt, int fade_in,
 	}
 
 	if (file_cnt) {
-		if ((retval = file_read (xfade_buf, fade_position, file_cnt, workbuf)) != (ssize_t) file_cnt) {
+		if ((retval = write_float (xfade_buf, fade_position, file_cnt)) != (ssize_t) file_cnt) {
 			if (retval >= 0 && errno == EAGAIN) {
 				/* XXX - can we really trust that errno is meaningful here?  yes POSIX, i'm talking to you.
 				 * short or no data there */
@@ -206,7 +196,7 @@ DestructiveFileSource::crossfade (Sample* data, jack_nframes_t cnt, int fade_in,
 	}
 	
 	if (nofade && !fade_in) {
-		if (file_write (data, file_pos, nofade, workbuf) != (ssize_t) nofade) {
+		if (write_float (data, file_pos, nofade) != nofade) {
 			error << string_compose(_("DestructiveFileSource: \"%1\" bad write (%2)"), _path, strerror (errno)) << endmsg;
 			return 0;
 		}
@@ -248,14 +238,14 @@ DestructiveFileSource::crossfade (Sample* data, jack_nframes_t cnt, int fade_in,
 	}
 
 	if (xfade) {
-		if (file_write (xfade_buf, fade_position, xfade, workbuf) != (ssize_t) xfade) {
+		if (write_float (xfade_buf, fade_position, xfade) != xfade) {
 			error << string_compose(_("DestructiveFileSource: \"%1\" bad write (%2)"), _path, strerror (errno)) << endmsg;
 			return 0;
 		}
 	}
 	
 	if (fade_in && nofade) {
-		if (file_write (data + xfade, file_pos + xfade, nofade, workbuf) != (ssize_t) nofade) {
+		if (write_float (data + xfade, file_pos + xfade, nofade) != nofade) {
 			error << string_compose(_("DestructiveFileSource: \"%1\" bad write (%2)"), _path, strerror (errno)) << endmsg;
 			return 0;
 		}
@@ -265,96 +255,100 @@ DestructiveFileSource::crossfade (Sample* data, jack_nframes_t cnt, int fade_in,
 }
 
 jack_nframes_t
-DestructiveFileSource::write (Sample* data, jack_nframes_t cnt, char * workbuf)
+DestructiveFileSource::write_unlocked (Sample* data, jack_nframes_t start, jack_nframes_t cnt, char * workbuf)
 {
-	{
-		Glib::Mutex::Lock lm (_lock);
-		
-		jack_nframes_t old_file_pos;
+	jack_nframes_t old_file_pos;
 
-		if (_capture_start && _capture_end) {
-			_capture_start = false;
-			_capture_end = false;
-
-			/* move to the correct location place */
-			file_pos = capture_start_frame;
-			
-			// split cnt in half
-			jack_nframes_t subcnt = cnt / 2;
-			jack_nframes_t ofilepos = file_pos;
-			
-			// fade in
-			if (crossfade (data, subcnt, 1, workbuf) != subcnt) {
-				return 0;
-			}
+	if (!writable()) {
+		return 0;
+	}
 
-			file_pos += subcnt;
-			Sample * tmpdata = data + subcnt;
-			
-			// fade out
-			subcnt = cnt - subcnt;
-			if (crossfade (tmpdata, subcnt, 0, workbuf) != subcnt) {
-				return 0;
-			}
+	if (_capture_start && _capture_end) {
+		_capture_start = false;
+		_capture_end = false;
+		
+		/* move to the correct location place */
+		file_pos = capture_start_frame;
+		
+		// split cnt in half
+		jack_nframes_t subcnt = cnt / 2;
+		jack_nframes_t ofilepos = file_pos;
+		
+		// fade in
+		if (crossfade (data, subcnt, 1, workbuf) != subcnt) {
+			return 0;
+		}
+		
+		file_pos += subcnt;
+		Sample * tmpdata = data + subcnt;
+		
+		// fade out
+		subcnt = cnt - subcnt;
+		if (crossfade (tmpdata, subcnt, 0, workbuf) != subcnt) {
+			return 0;
+		}
+		
+		file_pos = ofilepos; // adjusted below
+	}
+	else if (_capture_start) {
 
-			file_pos = ofilepos; // adjusted below
+		_capture_start = false;
+		_capture_end = false;
+		
+		/* move to the correct location place */
+		file_pos = capture_start_frame;
+		
+		if (crossfade (data, cnt, 1, workbuf) != cnt) {
+			return 0;
 		}
-		else if (_capture_start) {
-			_capture_start = false;
-			_capture_end = false;
+		
+	} else if (_capture_end) {
 
-			/* move to the correct location place */
-			file_pos = capture_start_frame;
-			
-			if (crossfade (data, cnt, 1, workbuf) != cnt) {
-				return 0;
-			}
+		_capture_start = false;
+		_capture_end = false;
+		
+		if (crossfade (data, cnt, 0, workbuf) != cnt) {
+			return 0;
+		}
 
-		} else if (_capture_end) {
-			_capture_start = false;
-			_capture_end = false;
+	} else {
 
-			if (crossfade (data, cnt, 0, workbuf) != cnt) {
-				return 0;
-			}
-		} else {
-			if (file_write(data, file_pos, cnt, workbuf) != (ssize_t) cnt) {
-				return 0;
-			}
+		if (write_float (data, file_pos, cnt) != cnt) {
+			return 0;
 		}
-
-		old_file_pos = file_pos;
-		if (file_pos + cnt > _length) {
-			_length = file_pos + cnt;
+	}
+	
+	old_file_pos = file_pos;
+	if (file_pos + cnt > _length) {
+		_length = file_pos + cnt;
+	}
+	file_pos += cnt;
+	
+	if (_build_peakfiles) {
+		PeakBuildRecord *pbr = 0;
+		
+		if (pending_peak_builds.size()) {
+			pbr = pending_peak_builds.back();
 		}
-		file_pos += cnt;
 		
-		if (_build_peakfiles) {
-			PeakBuildRecord *pbr = 0;
-			
-			if (pending_peak_builds.size()) {
-				pbr = pending_peak_builds.back();
-			}
+		if (pbr && pbr->frame + pbr->cnt == old_file_pos) {
 			
-			if (pbr && pbr->frame + pbr->cnt == old_file_pos) {
-				
-				/* the last PBR extended to the start of the current write,
-				   so just extend it again.
-				*/
-
-				pbr->cnt += cnt;
-			} else {
-				pending_peak_builds.push_back (new PeakBuildRecord (old_file_pos, cnt));
-			}
+			/* the last PBR extended to the start of the current write,
+			   so just extend it again.
+			*/
 			
-			_peaks_built = false;
+			pbr->cnt += cnt;
+		} else {
+			pending_peak_builds.push_back (new PeakBuildRecord (old_file_pos, cnt));
 		}
+		
+		_peaks_built = false;
 	}
 
 	if (_build_peakfiles) {
 		queue_for_peaks (*this);
 	}
-
+	
 	return cnt;
 }
 
@@ -367,7 +361,14 @@ DestructiveFileSource::last_capture_start_frame () const
 XMLNode& 
 DestructiveFileSource::get_state ()
 {
-	XMLNode& node = FileSource::get_state ();
+	XMLNode& node = AudioFileSource::get_state ();
 	node.add_property (X_("destructive"), "true");
 	return node;
 }
+
+void
+DestructiveFileSource::set_timeline_position (jack_nframes_t pos)
+{
+	/* destructive tracks always start at where our reference frame zero is */
+	timeline_position = 0;
+}
diff --git a/libs/ardour/externalsource.cc b/libs/ardour/externalsource.cc
deleted file mode 100644
index 7f478b6f53..0000000000
--- a/libs/ardour/externalsource.cc
+++ /dev/null
@@ -1,246 +0,0 @@
-/*
-    Copyright (C) 2006 Paul Davis 
-
-    This program is free software; you can redistribute it and/or modify
-    it under the terms of the GNU General Public License as published by
-    the Free Software Foundation; either version 2 of the License, or
-    (at your option) any later version.
-
-    This program is distributed in the hope that it will be useful,
-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    GNU General Public License for more details.
-
-    You should have received a copy of the GNU General Public License
-    along with this program; if not, write to the Free Software
-    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-
-*/
-
-#include <sys/stat.h>
-#include <unistd.h>
-#include <sys/time.h>
-
-#include <sndfile.h>
-
-#include <pbd/mountpoint.h>
-#include <ardour/externalsource.h>
-#include <ardour/sndfilesource.h>
-#include <ardour/sndfile_helpers.h>
-
-// if these headers come before sigc++ is included
-// the parser throws ObjC++ errors. (nil is a keyword)
-#ifdef HAVE_COREAUDIO 
-#include <ardour/coreaudio_source.h>
-#include <AudioToolbox/ExtendedAudioFile.h>
-#include <AudioToolbox/AudioFormat.h>
-#endif // HAVE_COREAUDIO
-
-#include "i18n.h"
-
-using namespace ARDOUR;
-
-string ExternalSource::peak_dir = "";
-
-ExternalSource::ExternalSource (const XMLNode& node)
-	: Source (node)
-{
-}
-
-ExternalSource::ExternalSource (const string& idstr, bool build_peak)
-	: Source(build_peak)
-{
-}
-
-ExternalSource::~ExternalSource ()
-{
-}
-
-jack_nframes_t
-ExternalSource::read_unlocked (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const
-{
-	return read (dst, start, cnt, workbuf);
-}
-
-string
-ExternalSource::peak_path (string audio_path)
-{
-	/* XXX hardly bombproof! fix me */
-
-	struct stat stat_file;
-	struct stat stat_mount;
-
-	string mp = mountpoint (audio_path);
-
-	stat (audio_path.c_str(), &stat_file);
-	stat (mp.c_str(), &stat_mount);
-
-	char buf[32];
-#ifdef __APPLE__
-	snprintf (buf, sizeof (buf), "%u-%u-%d.peak", stat_mount.st_ino, stat_file.st_ino, channel);
-#else
-	snprintf (buf, sizeof (buf), "%ld-%ld-%d.peak", stat_mount.st_ino, stat_file.st_ino, channel);
-#endif
-
-	string res = peak_dir;
-	res += buf;
-
-	return res;
-}
-
-#ifdef HAVE_COREAUDIO
-
-ExternalSource*
-ExternalSource::create (const XMLNode& node)
-{
-	ExternalSource* es = 0;
-
-	try {
-		es = new CoreAudioSource (node);
-	} 
-	
-	catch (failed_constructor& err) {
-		es = new SndFileSource (node);
-	}
-
-	es = new SndFileSource (node);
-
-	return es;
-}
-
-#else
-
-ExternalSource*
-ExternalSource::create (const XMLNode& node)
-{
-	return new SndFileSource (node);
-}
-
-#endif // HAVE_COREAUDIO
-
-#ifdef HAVE_COREAUDIO
-ExternalSource*
-ExternalSource::create (const string& idstr, bool build_peak)
-{
-	ExternalSource* es = 0;
-
-	try {
-		es = new CoreAudioSource (idstr, build_peak);
-	}
-
-	catch (failed_constructor& err) {
-		es = new SndFileSource (idstr, build_peak);
-	}
-
-	return es;
-}
-
-#else
-
-ExternalSource*
-ExternalSource::create (const string& idstr, bool build_peak)
-{
-	return new SndFileSource (idstr, build_peak);
-}
-
-#endif // HAVE_COREAUDIO
-
-#ifdef HAVE_COREAUDIO
-std::string 
-CFStringRefToStdString(CFStringRef stringRef)
-{
-	CFIndex size = 
-		CFStringGetMaximumSizeForEncoding(CFStringGetLength(stringRef) , 
-		kCFStringEncodingASCII);
-	    char *buf = new char[size];
-	
-	std::string result;
-
-	if(CFStringGetCString(stringRef, buf, size, kCFStringEncodingASCII)) {
-	    result = buf;
-	}
-	delete [] buf;
-	return result;
-}
-#endif // HAVE_COREAUDIO
-
-bool
-ExternalSource::get_soundfile_info (string path, SoundFileInfo& _info, string& error_msg)
-{
-#ifdef HAVE_COREAUDIO
-	OSStatus err = noErr;
-    FSRef ref; 
-	ExtAudioFileRef af = 0;
-	size_t size;
-    CFStringRef name;
-
-    err = FSPathMakeRef ((UInt8*)path.c_str(), &ref, 0);
-	if (err != noErr) {
-        ExtAudioFileDispose (af);
-		goto libsndfile;
-	}
-
-	err = ExtAudioFileOpen(&ref, &af);
-	if (err != noErr) {
-        ExtAudioFileDispose (af);
-		goto libsndfile;
-	}
-
-	AudioStreamBasicDescription absd;
-	memset(&absd, 0, sizeof(absd));
-	size = sizeof(AudioStreamBasicDescription);
-	err = ExtAudioFileGetProperty(af,
-			kExtAudioFileProperty_FileDataFormat, &size, &absd);
-	if (err != noErr) {
-        ExtAudioFileDispose (af);
-		goto libsndfile;
-	}
-
-	_info.samplerate = absd.mSampleRate;
-	_info.channels   = absd.mChannelsPerFrame;
-
-    size = sizeof(_info.length);
-    err = ExtAudioFileGetProperty(af, kExtAudioFileProperty_FileLengthFrames, &size, &_info.length);
-    if (err != noErr) {
-        ExtAudioFileDispose (af);
-		goto libsndfile;
-    }
-
-	size = sizeof(CFStringRef);
-	err = AudioFormatGetProperty(
-			kAudioFormatProperty_FormatName, sizeof(absd), &absd, &size, &name);
-	if (err != noErr) {
-        ExtAudioFileDispose (af);
-		goto libsndfile;
-	}
-
-	_info.format_name = CFStringRefToStdString(name);
-
-    ExtAudioFileDispose (af);
-	return true;
-	
-libsndfile:
-#endif // HAVE_COREAUDIO
-
-	SNDFILE *sf;
-	SF_INFO sf_info;
-
-	sf_info.format = 0; // libsndfile says to clear this before sf_open().
-
-	if ((sf = sf_open ((char*) path.c_str(), SFM_READ, &sf_info)) == 0) { 
-		char errbuf[256];
-		error_msg = sf_error_str (0, errbuf, sizeof (errbuf) - 1);
-		return false;
-	}
-
-	sf_close (sf);
-
-	_info.samplerate  = sf_info.samplerate;
-	_info.channels    = sf_info.channels;
-	_info.length      = sf_info.frames;
-	_info.format_name = string_compose("Format: %1, %2",
-			sndfile_major_format(sf_info.format),
-			sndfile_minor_format(sf_info.format));
-
-	return true;
-}
diff --git a/libs/ardour/filesource.cc b/libs/ardour/filesource.cc
index 63a9a3d014..0e0ef0bc1e 100644
--- a/libs/ardour/filesource.cc
+++ b/libs/ardour/filesource.cc
@@ -62,8 +62,7 @@
 
 #include <ardour/ardour.h>
 #include <ardour/version.h>
-#include <ardour/source.h>
-#include <ardour/filesource.h>
+#include <ardour/audiofilesource.h>
 #include <ardour/session.h>
 #include <ardour/cycle_timer.h>
 #include <ardour/pcm_utils.h>
diff --git a/libs/ardour/globals.cc b/libs/ardour/globals.cc
index 8e36ca8074..aa725d4bb3 100644
--- a/libs/ardour/globals.cc
+++ b/libs/ardour/globals.cc
@@ -43,7 +43,7 @@
 #include <ardour/audio_library.h>
 #include <ardour/configuration.h>
 #include <ardour/plugin_manager.h>
-#include <ardour/source.h>
+#include <ardour/audiosource.h>
 #include <ardour/utils.h>
 #include <ardour/session.h>
 #include <ardour/control_protocol_manager.h>
diff --git a/libs/ardour/import.cc b/libs/ardour/import.cc
index c13816e648..410171a590 100644
--- a/libs/ardour/import.cc
+++ b/libs/ardour/import.cc
@@ -36,8 +36,8 @@
 
 #include <ardour/ardour.h>
 #include <ardour/session.h>
-#include <ardour/diskstream.h>
-#include <ardour/filesource.h>
+#include <ardour/audio_diskstream.h>
+#include <ardour/sndfilesource.h>
 #include <ardour/sndfile_helpers.h>
 #include <ardour/audioregion.h>
 
@@ -51,8 +51,8 @@ int
 Session::import_audiofile (import_status& status)
 {
 	SNDFILE *in;
-	FileSource **newfiles = 0;
-	ARDOUR::AudioRegion::SourceList sources;
+	AudioFileSource **newfiles = 0;
+	AudioRegion::SourceList sources;
 	SF_INFO info;
 	float *data = 0;
 	Sample **channel_data = 0;
@@ -94,7 +94,7 @@ Session::import_audiofile (import_status& status)
 		}
 	}
 
-	newfiles = new FileSource *[info.channels];
+	newfiles = new AudioFileSource *[info.channels];
 	for (n = 0; n < info.channels; ++n) {
 		newfiles[n] = 0;
 	}
@@ -137,7 +137,10 @@ Session::import_audiofile (import_status& status)
 
 			
 		try { 
-			newfiles[n] = new FileSource (buf, frame_rate(), false, Config->get_native_file_data_format());
+			newfiles[n] = new SndFileSource (buf, 
+							 Config->get_native_file_data_format(),
+							 Config->get_native_file_header_format(),
+							 frame_rate ());
 		}
 
 		catch (failed_constructor& err) {
diff --git a/libs/ardour/osc.cc b/libs/ardour/osc.cc
index 67b70fba0c..5aaf9d5591 100644
--- a/libs/ardour/osc.cc
+++ b/libs/ardour/osc.cc
@@ -309,7 +309,6 @@ OSC::osc_receiver()
 		if ((ret = poll (pfd, nfds, timeout)) < 0) {
 			if (errno == EINTR) {
 				/* gdb at work, perhaps */
-				cerr << "EINTR hit " << endl;
 				goto again;
 			}
 			
diff --git a/libs/ardour/reverse.cc b/libs/ardour/reverse.cc
index 335dacad6e..13dd531bac 100644
--- a/libs/ardour/reverse.cc
+++ b/libs/ardour/reverse.cc
@@ -24,7 +24,7 @@
 
 #include <ardour/types.h>
 #include <ardour/reverse.h>
-#include <ardour/filesource.h>
+#include <ardour/audiofilesource.h>
 #include <ardour/session.h>
 #include <ardour/audioregion.h>
 
diff --git a/libs/ardour/route_group.cc b/libs/ardour/route_group.cc
index ae807e66e1..5730623742 100644
--- a/libs/ardour/route_group.cc
+++ b/libs/ardour/route_group.cc
@@ -29,7 +29,7 @@
 
 #include <ardour/route_group.h>
 #include <ardour/audio_track.h>
-#include <ardour/diskstream.h>
+#include <ardour/audio_diskstream.h>
 #include <ardour/configuration.h>
 
 using namespace ARDOUR;
diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index 6c1dec8e81..d7d7e290ed 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -32,7 +32,8 @@
 #include <sigc++/bind.h>
 #include <sigc++/retype.h>
 
-#include <glibmm.h>
+#include <glibmm/thread.h>
+#include <glibmm/miscutils.h>
 
 #include <pbd/error.h>
 #include <glibmm/thread.h>
@@ -43,14 +44,12 @@
 #include <ardour/audioengine.h>
 #include <ardour/configuration.h>
 #include <ardour/session.h>
-#include <ardour/diskstream.h>
+#include <ardour/audio_diskstream.h>
 #include <ardour/utils.h>
 #include <ardour/audioplaylist.h>
 #include <ardour/audioregion.h>
-#include <ardour/source.h>
-#include <ardour/filesource.h>
+#include <ardour/audiofilesource.h>
 #include <ardour/destructive_filesource.h>
-#include <ardour/sndfilesource.h>
 #include <ardour/auditioner.h>
 #include <ardour/recent_sessions.h>
 #include <ardour/redirect.h>
@@ -90,6 +89,7 @@ Session::mix_buffers_with_gain_t	Session::mix_buffers_with_gain 	= 0;
 Session::mix_buffers_no_gain_t		Session::mix_buffers_no_gain 	= 0;
 
 sigc::signal<int> Session::AskAboutPendingState;
+sigc::signal<void> Session::SMPTEOffsetChanged;
 
 int
 Session::find_session (string str, string& path, string& snapshot, bool& isnew)
@@ -456,10 +456,10 @@ Session::~Session ()
 	}
 
 #ifdef TRACK_DESTRUCTION
-	cerr << "delete diskstreams\n";
+	cerr << "delete audio_diskstreams\n";
 #endif /* TRACK_DESTRUCTION */
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ) {
-		DiskStreamList::iterator tmp;
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ) {
+		AudioDiskstreamList::iterator tmp;
 
 		tmp = i;
 		++tmp;
@@ -470,10 +470,10 @@ Session::~Session ()
 	}
 
 #ifdef TRACK_DESTRUCTION
-	cerr << "delete sources\n";
+	cerr << "delete audio sources\n";
 #endif /* TRACK_DESTRUCTION */
-	for (SourceList::iterator i = sources.begin(); i != sources.end(); ) {
-		SourceList::iterator tmp;
+	for (AudioSourceList::iterator i = audio_sources.begin(); i != audio_sources.end(); ) {
+		AudioSourceList::iterator tmp;
 
 		tmp = i;
 		++tmp;
@@ -882,7 +882,7 @@ Session::playlist_length_changed (Playlist* pl)
 }
 
 void
-Session::diskstream_playlist_changed (DiskStream* dstream)
+Session::diskstream_playlist_changed (AudioDiskstream* dstream)
 {
 	Playlist *playlist;
 
@@ -962,7 +962,7 @@ Session::set_auto_input (bool yn)
 			   The rarity and short potential lock duration makes this "OK"
 			*/
 			Glib::RWLock::ReaderLock dsm (diskstream_lock);
-			for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+			for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
 					//cerr << "switching to input = " << !auto_input << __FILE__ << __LINE__ << endl << endl;
 					(*i)->monitor_input (!auto_input);   
@@ -980,7 +980,7 @@ Session::reset_input_monitor_state ()
 {
 	if (transport_rolling()) {
 		Glib::RWLock::ReaderLock dsm (diskstream_lock);
-		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 			if ((*i)->record_enabled ()) {
 				//cerr << "switching to input = " << !auto_input << __FILE__ << __LINE__ << endl << endl;
 				(*i)->monitor_input (Config->get_use_hardware_monitoring() && !auto_input);
@@ -988,7 +988,7 @@ Session::reset_input_monitor_state ()
 		}
 	} else {
 		Glib::RWLock::ReaderLock dsm (diskstream_lock);
-		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 			if ((*i)->record_enabled ()) {
 				//cerr << "switching to input = " << !auto_input << __FILE__ << __LINE__ << endl << endl;
 				(*i)->monitor_input (Config->get_use_hardware_monitoring());
@@ -1069,7 +1069,7 @@ Session::auto_loop_changed (Location* location)
 		}
 		else if (seamless_loop && !loop_changing) {
 			
-			// schedule a locate-roll to refill the diskstreams at the
+			// schedule a locate-roll to refill the audio_diskstreams at the
 			// previous loop end
 			loop_changing = true;
 
@@ -1257,7 +1257,7 @@ Session::enable_record ()
 	if (g_atomic_int_get (&_record_status) != Recording) {
 		g_atomic_int_set (&_record_status, Recording);
 		_last_record_location = _transport_frame;
-		//send_mmc_in_another_thread (MIDI::MachineControl::cmdRecordStrobe);
+		deliver_mmc(MIDI::MachineControl::cmdRecordStrobe, _last_record_location);
 
 		if (Config->get_use_hardware_monitoring() && auto_input) {
 			/* Even though this can be called from RT context we are using
@@ -1266,7 +1266,7 @@ Session::enable_record ()
 			*/
 			Glib::RWLock::ReaderLock dsm (diskstream_lock);
 			
-			for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+			for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
 					(*i)->monitor_input (true);   
 				}
@@ -1292,7 +1292,11 @@ Session::disable_record (bool rt_context, bool force)
 			}
 		}
 
-		//send_mmc_in_another_thread (MIDI::MachineControl::cmdRecordExit);
+		// FIXME: timestamp correct? [DR]
+		// FIXME FIXME FIXME: rt_context?  this must be called in the process thread.
+		// does this /need/ to be sent in all cases?
+		if (rt_context)
+			deliver_mmc (MIDI::MachineControl::cmdRecordExit, _transport_frame);
 
 		if (Config->get_use_hardware_monitoring() && auto_input) {
 			/* Even though this can be called from RT context we are using
@@ -1301,7 +1305,7 @@ Session::disable_record (bool rt_context, bool force)
 			*/
 			Glib::RWLock::ReaderLock dsm (diskstream_lock);
 			
-			for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+			for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
 					(*i)->monitor_input (false);   
 				}
@@ -1328,7 +1332,7 @@ Session::step_back_from_record ()
 		*/
 		Glib::RWLock::ReaderLock dsm (diskstream_lock);
 		
-		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		        if (auto_input && (*i)->record_enabled ()) {
 			        //cerr << "switching from input" << __FILE__ << __LINE__ << endl << endl;
 		                (*i)->monitor_input (false);   
@@ -1353,8 +1357,7 @@ Session::maybe_enable_record ()
 			enable_record ();
 		} 
 	} else {
-		// FIXME
-		//send_mmc_in_another_thread (MIDI::MachineControl::cmdRecordPause);
+		deliver_mmc (MIDI::MachineControl::cmdRecordPause, _transport_frame);
 		RecordStateChanged (); /* EMIT SIGNAL */
 	}
 
@@ -1434,6 +1437,9 @@ Session::set_frame_rate (jack_nframes_t frames_per_second)
 
 	Route::set_automation_interval ((jack_nframes_t) ceil ((double) frames_per_second * 0.25));
 
+	// XXX we need some equivalent to this, somehow
+	// DestructiveFileSource::setup_standard_crossfades (frames_per_second);
+
 	set_dirty();
 
 	/* XXX need to reset/reinstantiate all LADSPA plugins */
@@ -1495,7 +1501,7 @@ Session::set_block_size (jack_nframes_t nframes)
 			(*i)->set_block_size (nframes);
 		}
 		
-		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 			(*i)->set_block_size (nframes);
 		}
 
@@ -1902,14 +1908,14 @@ Session::add_route (Route* route)
 }
 
 void
-Session::add_diskstream (DiskStream* dstream)
+Session::add_diskstream (AudioDiskstream* dstream)
 {
 	/* need to do this in case we're rolling at the time, to prevent false underruns */
 	dstream->do_refill(0, 0, 0);
 	
 	{ 
 		Glib::RWLock::WriterLock lm (diskstream_lock);
-		diskstreams.push_back (dstream);
+		audio_diskstreams.push_back (dstream);
 	}
 
 	/* take a reference to the diskstream, preventing it from
@@ -1929,7 +1935,7 @@ Session::add_diskstream (DiskStream* dstream)
 	set_dirty();
 	save_state (_current_snapshot_name);
 
-	DiskStreamAdded (dstream); /* EMIT SIGNAL */
+	AudioDiskstreamAdded (dstream); /* EMIT SIGNAL */
 }
 
 void
@@ -1963,18 +1969,24 @@ Session::remove_route (Route& route)
 		update_route_solo_state ();
 	}
 
-	{
-		Glib::RWLock::WriterLock lm (diskstream_lock);
-
-		AudioTrack* at;
+	AudioTrack* at;
+	AudioDiskstream* ds = 0;
+	
+	if ((at = dynamic_cast<AudioTrack*>(&route)) != 0) {
+		ds = &at->disk_stream();
+	}
+	
+	if (ds) {
 
-		if ((at = dynamic_cast<AudioTrack*>(&route)) != 0) {
-			diskstreams.remove (&at->disk_stream());
-			at->disk_stream().unref ();
+		{
+			Glib::RWLock::WriterLock lm (diskstream_lock);
+			audio_diskstreams.remove (ds);
 		}
 
-		find_current_end ();
+		ds->unref ();
 	}
+
+	find_current_end ();
 	
 	update_latency_compensation (false, false);
 	set_dirty();
@@ -2257,7 +2269,7 @@ Session::get_maximum_extent () const
 	   ensure atomicity.
 	*/
 
-	for (DiskStreamList::const_iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::const_iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		Playlist* pl = (*i)->playlist();
 		if ((me = pl->get_maximum_extent()) > max) {
 			max = me;
@@ -2267,12 +2279,12 @@ Session::get_maximum_extent () const
 	return max;
 }
 
-DiskStream *
+AudioDiskstream *
 Session::diskstream_by_name (string name)
 {
 	Glib::RWLock::ReaderLock lm (diskstream_lock);
 
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		if ((*i)->name() == name) {
 			return* i;
 		}
@@ -2281,12 +2293,12 @@ Session::diskstream_by_name (string name)
 	return 0;
 }
 
-DiskStream *
+AudioDiskstream *
 Session::diskstream_by_id (id_t id)
 {
 	Glib::RWLock::ReaderLock lm (diskstream_lock);
 
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		if ((*i)->id() == id) {
 			return *i;
 		}
@@ -2585,7 +2597,10 @@ Session::destroy_region (Region* region)
 	for (vector<Source*>::iterator i = srcs.begin(); i != srcs.end(); ++i) {
 		
 		if ((*i)->use_cnt() == 0) {
-			(*i)->mark_for_remove ();
+			AudioFileSource* afs = dynamic_cast<AudioFileSource*>(*i);
+			if (afs) {
+				(afs)->mark_for_remove ();
+			}
 			delete *i;
 		}
 	}
@@ -2609,7 +2624,7 @@ Session::remove_last_capture ()
 
 	Glib::RWLock::ReaderLock lm (diskstream_lock);
 	
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		list<Region*>& l = (*i)->last_capture_regions();
 		
 		if (!l.empty()) {
@@ -2632,15 +2647,15 @@ Session::remove_region_from_region_list (Region& r)
 /* Source Management */
 
 void
-Session::add_source (Source* source)
+Session::add_audio_source (AudioSource* source)
 {
-	pair<SourceList::key_type, SourceList::mapped_type> entry;
+	pair<AudioSourceList::key_type, AudioSourceList::mapped_type> entry;
 
 	{
-		Glib::Mutex::Lock lm (source_lock);
+		Glib::Mutex::Lock lm (audio_source_lock);
 		entry.first = source->id();
 		entry.second = source;
-		sources.insert (entry);
+		audio_sources.insert (entry);
 	}
 	
 	source->GoingAway.connect (mem_fun (this, &Session::remove_source));
@@ -2652,13 +2667,13 @@ Session::add_source (Source* source)
 void
 Session::remove_source (Source* source)
 {
-	SourceList::iterator i;
+	AudioSourceList::iterator i;
 
 	{ 
-		Glib::Mutex::Lock lm (source_lock);
+		Glib::Mutex::Lock lm (audio_source_lock);
 
-		if ((i = sources.find (source->id())) != sources.end()) {
-			sources.erase (i);
+		if ((i = audio_sources.find (source->id())) != audio_sources.end()) {
+			audio_sources.erase (i);
 		}
 	}
 
@@ -2677,15 +2692,21 @@ Session::remove_source (Source* source)
 Source *
 Session::get_source (ARDOUR::id_t id)
 {
-	Glib::Mutex::Lock lm (source_lock);
-	SourceList::iterator i;
+	Glib::Mutex::Lock lm (audio_source_lock);
+	AudioSourceList::iterator i;
 	Source* source = 0;
 
-	if ((i = sources.find (id)) != sources.end()) {
+	if ((i = audio_sources.find (id)) != audio_sources.end()) {
 		source = (*i).second;
 	}
 
-	return source;
+	if (source) {
+		return source;
+	}
+
+	/* XXX search MIDI or other searches here */
+	
+	return 0;
 }
 
 string
@@ -2892,17 +2913,23 @@ Session::audio_path_from_name (string name, uint32_t nchan, uint32_t chan, bool
 	return spath;
 }
 
-FileSource *
-Session::create_file_source (DiskStream& ds, int32_t chan, bool destructive)
+AudioFileSource *
+Session::create_audio_source_for_session (AudioDiskstream& ds, uint32_t chan, bool destructive)
 {
 	string spath = audio_path_from_name (ds.name(), ds.n_channels(), chan, destructive);
 
 	/* this might throw failed_constructor(), which is OK */
-
+	
 	if (destructive) {
-		return new DestructiveFileSource (spath, frame_rate(), false, Config->get_native_file_data_format());
+		return new DestructiveFileSource (spath,
+						  Config->get_native_file_data_format(),
+						  Config->get_native_file_header_format(),
+						  frame_rate());
 	} else {
-		return new FileSource (spath, frame_rate(), false, Config->get_native_file_data_format());
+		return new SndFileSource (spath, 
+					  Config->get_native_file_data_format(),
+					  Config->get_native_file_header_format(),
+					  frame_rate());
 	}
 }
 
@@ -3084,7 +3111,7 @@ Session::remove_empty_sounds ()
 	
 	for (vector<string *>::iterator i = possible_audiofiles->begin(); i != possible_audiofiles->end(); ++i) {
 
-		if (FileSource::is_empty (*(*i))) {
+		if (AudioFileSource::is_empty (*(*i))) {
 
 			unlink ((*i)->c_str());
 			
@@ -3142,12 +3169,12 @@ Session::set_all_mute (bool yn)
 }
 		
 uint32_t
-Session::n_diskstreams () const
+Session::n_audio_diskstreams () const
 {
 	Glib::RWLock::ReaderLock lm (diskstream_lock);
 	uint32_t n = 0;
 
-	for (DiskStreamList::const_iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::const_iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		if (!(*i)->hidden()) {
 			n++;
 		}
@@ -3156,10 +3183,10 @@ Session::n_diskstreams () const
 }
 
 void 
-Session::foreach_diskstream (void (DiskStream::*func)(void)) 
+Session::foreach_audio_diskstream (void (AudioDiskstream::*func)(void)) 
 {
 	Glib::RWLock::ReaderLock lm (diskstream_lock);
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		if (!(*i)->hidden()) {
 			((*i)->*func)();
 		}
@@ -3186,7 +3213,7 @@ Session::graph_reordered ()
 	   reflect any changes in latencies within the graph.
 	*/
 	
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		(*i)->set_capture_offset ();
 	}
 }
@@ -3469,7 +3496,7 @@ Session::reset_native_file_format ()
 	//RWLockMonitor lm1 (route_lock, true, __LINE__, __FILE__);
 	Glib::RWLock::ReaderLock lm2 (diskstream_lock);
 
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		(*i)->reset_write_sources (false);
 	}
 }
@@ -3489,7 +3516,7 @@ Session::route_name_unique (string n) const
 }
 
 int
-Session::remove_file_source (FileSource& fs)
+Session::cleanup_audio_file_source (AudioFileSource& fs)
 {
 	return fs.move_to_trash (dead_sound_dir_name);
 }
@@ -3564,12 +3591,12 @@ Session::freeze (InterThreadInfo& itt)
 }
 
 int
-Session::write_one_track (AudioTrack& track, jack_nframes_t start, jack_nframes_t len, 	bool overwrite, vector<Source*>& srcs,
-			  InterThreadInfo& itt)
+Session::write_one_audio_track (AudioTrack& track, jack_nframes_t start, jack_nframes_t len, 	
+			       bool overwrite, vector<AudioSource*>& srcs, InterThreadInfo& itt)
 {
 	int ret = -1;
 	Playlist* playlist;
-	FileSource* fsource;
+	AudioFileSource* fsource;
 	uint32_t x;
 	char buf[PATH_MAX+1];
 	string dir;
@@ -3614,7 +3641,11 @@ Session::write_one_track (AudioTrack& track, jack_nframes_t start, jack_nframes_
 		}
 		
 		try {
-			fsource = new FileSource (buf, frame_rate(), false, Config->get_native_file_data_format());
+			fsource =  new SndFileSource (buf, 
+						      Config->get_native_file_data_format(),
+						      Config->get_native_file_header_format(),
+						      frame_rate());
+							    
 		}
 		
 		catch (failed_constructor& err) {
@@ -3653,9 +3684,13 @@ Session::write_one_track (AudioTrack& track, jack_nframes_t start, jack_nframes_
 		}
 
 		uint32_t n = 0;
-		for (vector<Source*>::iterator src=srcs.begin(); src != srcs.end(); ++src, ++n) {
-			if ((*src)->write (buffers[n], this_chunk, workbuf) != this_chunk) {
-				goto out;
+		for (vector<AudioSource*>::iterator src=srcs.begin(); src != srcs.end(); ++src, ++n) {
+			AudioFileSource* afs = dynamic_cast<AudioFileSource*>(*src);
+
+			if (afs) {
+				if (afs->write (buffers[n], this_chunk, workbuf) != this_chunk) {
+					goto out;
+				}
 			}
 		}
 		
@@ -3673,14 +3708,20 @@ Session::write_one_track (AudioTrack& track, jack_nframes_t start, jack_nframes_
 		time (&now);
 		xnow = localtime (&now);
 		
-		for (vector<Source*>::iterator src=srcs.begin(); src != srcs.end(); ++src) {
-			dynamic_cast<FileSource*>((*src))->update_header (position, *xnow, now);
+		for (vector<AudioSource*>::iterator src=srcs.begin(); src != srcs.end(); ++src) {
+			AudioFileSource* afs = dynamic_cast<AudioFileSource*>(*src);
+			if (afs) {
+				afs->update_header (position, *xnow, now);
+			}
 		}
 		
 		/* build peakfile for new source */
 		
-		for (vector<Source*>::iterator src=srcs.begin(); src != srcs.end(); ++src) {
-			dynamic_cast<FileSource*>(*src)->build_peaks ();
+		for (vector<AudioSource*>::iterator src=srcs.begin(); src != srcs.end(); ++src) {
+			AudioFileSource* afs = dynamic_cast<AudioFileSource*>(*src);
+			if (afs) {
+				afs->build_peaks ();
+			}
 		}
 		
 		ret = 0;
@@ -3688,8 +3729,11 @@ Session::write_one_track (AudioTrack& track, jack_nframes_t start, jack_nframes_
 		
   out:
 	if (ret) {
-		for (vector<Source*>::iterator src=srcs.begin(); src != srcs.end(); ++src) {
-			dynamic_cast<FileSource*>(*src)->mark_for_remove ();
+		for (vector<AudioSource*>::iterator src=srcs.begin(); src != srcs.end(); ++src) {
+			AudioFileSource* afs = dynamic_cast<AudioFileSource*>(*src);
+			if (afs) {
+				afs->mark_for_remove ();
+			}
 			delete *src;
 		}
 	}
diff --git a/libs/ardour/session_butler.cc b/libs/ardour/session_butler.cc
index ebe0d64548..d29bf3937b 100644
--- a/libs/ardour/session_butler.cc
+++ b/libs/ardour/session_butler.cc
@@ -34,7 +34,7 @@
 #include <ardour/configuration.h>
 #include <ardour/audioengine.h>
 #include <ardour/session.h>
-#include <ardour/diskstream.h>
+#include <ardour/audio_diskstream.h>
 #include <ardour/crossfade.h>
 #include <ardour/timestamps.h>
 
@@ -168,10 +168,10 @@ Session::butler_thread_work ()
 	struct timeval begin, end;
 	struct pollfd pfd[1];
 	bool disk_work_outstanding = false;
-	DiskStreamList::iterator i;
+	AudioDiskstreamList::iterator i;
 
-	butler_mixdown_buffer = new Sample[DiskStream::disk_io_frames()];
-	butler_gain_buffer = new gain_t[DiskStream::disk_io_frames()];
+	butler_mixdown_buffer = new Sample[AudioDiskstream::disk_io_frames()];
+	butler_gain_buffer = new gain_t[AudioDiskstream::disk_io_frames()];
 	// this buffer is used for temp conversion purposes in filesources
 	char * conv_buffer = conversion_buffer(ButlerContext);
 
@@ -241,7 +241,7 @@ Session::butler_thread_work ()
 			}
 		}
 	
-		for (i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+		for (i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 			// cerr << "BEFORE " << (*i)->name() << ": pb = " << (*i)->playback_buffer_load() << " cp = " << (*i)->capture_buffer_load() << endl;
 		}
 
@@ -257,7 +257,7 @@ Session::butler_thread_work ()
 
 		Glib::RWLock::ReaderLock dsm (diskstream_lock);
 		
-		for (i = diskstreams.begin(); !transport_work_requested() && butler_should_run && i != diskstreams.end(); ++i) {
+		for (i = audio_diskstreams.begin(); !transport_work_requested() && butler_should_run && i != audio_diskstreams.end(); ++i) {
 			
 			// cerr << "rah fondr " << (*i)->io()->name () << endl;
 
@@ -278,7 +278,7 @@ Session::butler_thread_work ()
 
 		}
 
-		if (i != diskstreams.end()) {
+		if (i != audio_diskstreams.end()) {
 			/* we didn't get to all the streams */
 			disk_work_outstanding = true;
 		}
@@ -300,7 +300,7 @@ Session::butler_thread_work ()
 		compute_io = true;
 		gettimeofday (&begin, 0);
 		
-		for (i = diskstreams.begin(); !transport_work_requested() && butler_should_run && i != diskstreams.end(); ++i) {
+		for (i = audio_diskstreams.begin(); !transport_work_requested() && butler_should_run && i != audio_diskstreams.end(); ++i) {
 			
 			// cerr << "write behind for " << (*i)->name () << endl;
 			
@@ -330,7 +330,7 @@ Session::butler_thread_work ()
 			request_stop ();
 		}
 
-		if (i != diskstreams.end()) {
+		if (i != audio_diskstreams.end()) {
 			/* we didn't get to all the streams */
 			disk_work_outstanding = true;
 		}
@@ -357,7 +357,7 @@ Session::butler_thread_work ()
 			Glib::Mutex::Lock lm (butler_request_lock);
 
 			if (butler_should_run && (disk_work_outstanding || transport_work_requested())) {
-//				for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+//				for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 //					cerr << "AFTER " << (*i)->name() << ": pb = " << (*i)->playback_buffer_load() << " cp = " << (*i)->capture_buffer_load() << endl;
 //				}
 
@@ -375,7 +375,7 @@ Session::butler_thread_work ()
 
 
 void
-Session::request_overwrite_buffer (DiskStream* stream)
+Session::request_overwrite_buffer (AudioDiskstream* stream)
 {
 	Event *ev = new Event (Event::Overwrite, Event::Add, Event::Immediate, 0, 0, 0.0);
 	ev->set_ptr (stream);
@@ -383,7 +383,7 @@ Session::request_overwrite_buffer (DiskStream* stream)
 }
 
 void
-Session::overwrite_some_buffers (DiskStream* ds)
+Session::overwrite_some_buffers (AudioDiskstream* ds)
 {
 	/* executed by the audio thread */
 
@@ -398,7 +398,7 @@ Session::overwrite_some_buffers (DiskStream* ds)
 	} else {
 
 		Glib::RWLock::ReaderLock dm (diskstream_lock);
-		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 			(*i)->set_pending_overwrite (true);
 		}
 	}
diff --git a/libs/ardour/session_events.cc b/libs/ardour/session_events.cc
index c9b4339686..586dea05a3 100644
--- a/libs/ardour/session_events.cc
+++ b/libs/ardour/session_events.cc
@@ -28,7 +28,7 @@
 
 #include <ardour/ardour.h>
 #include <ardour/session.h>
-#include <ardour/diskstream.h>
+#include <ardour/audio_diskstream.h>
 
 #include "i18n.h"
 
@@ -393,11 +393,11 @@ Session::process_event (Event* ev)
 		break;
 
 	case Event::Overwrite:
-		overwrite_some_buffers (static_cast<DiskStream*>(ev->ptr));
+		overwrite_some_buffers (static_cast<AudioDiskstream*>(ev->ptr));
 		break;
 
 	case Event::SetDiskstreamSpeed:
-		set_diskstream_speed (static_cast<DiskStream*> (ev->ptr), ev->speed);
+		set_diskstream_speed (static_cast<AudioDiskstream*> (ev->ptr), ev->speed);
 		break;
 
 	case Event::SetSlaveSource:
diff --git a/libs/ardour/session_export.cc b/libs/ardour/session_export.cc
index 183b6df237..f6ea0c9f3f 100644
--- a/libs/ardour/session_export.cc
+++ b/libs/ardour/session_export.cc
@@ -47,7 +47,7 @@
 #include <ardour/sndfile_helpers.h>
 #include <ardour/port.h>
 #include <ardour/audioengine.h>
-#include <ardour/diskstream.h>
+#include <ardour/audio_diskstream.h>
 #include <ardour/panner.h>
 
 #include "i18n.h"
@@ -495,7 +495,7 @@ Session::prepare_to_export (AudioExportSpecification& spec)
 
 	{
 		Glib::RWLock::ReaderLock lm (diskstream_lock);
-		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 			if ((*i)-> seek (spec.start_frame, true)) {
 				error << string_compose (_("%1: cannot seek to %2 for export"),
 						  (*i)->name(), spec.start_frame)
diff --git a/libs/ardour/session_feedback.cc b/libs/ardour/session_feedback.cc
index ea8580b3c2..b409686ce7 100644
--- a/libs/ardour/session_feedback.cc
+++ b/libs/ardour/session_feedback.cc
@@ -38,7 +38,7 @@
 #include <ardour/audioengine.h>
 #include <ardour/session.h>
 #include <ardour/audio_track.h>
-#include <ardour/diskstream.h>
+#include <ardour/audio_diskstream.h>
 #include <ardour/control_protocol.h>
 
 #include "i18n.h"
diff --git a/libs/ardour/session_midi.cc b/libs/ardour/session_midi.cc
index 9b6f0bf6ba..f1c4b1e84d 100644
--- a/libs/ardour/session_midi.cc
+++ b/libs/ardour/session_midi.cc
@@ -38,7 +38,7 @@
 #include <ardour/audioengine.h>
 #include <ardour/session.h>
 #include <ardour/audio_track.h>
-#include <ardour/diskstream.h>
+#include <ardour/audio_diskstream.h>
 #include <ardour/slave.h>
 #include <ardour/cycles.h>
 #include <ardour/smpte.h>
@@ -1016,10 +1016,15 @@ Session::send_mmc_in_another_thread (MIDI::MachineControl::Command cmd, jack_nfr
 	poke_midi_thread ();
 }
 */
+
+/** Send an MMC command at the given absolute timestamp (@a where).
+ *
+ * This must be called in the process thread, and @a where must fall within
+ * this process cycle or horrible things will happen.
+ */
 void
 Session::deliver_mmc (MIDI::MachineControl::Command cmd, jack_nframes_t where)
 {
-#if 0
 	using namespace MIDI;
 	int nbytes = 4;
 	SMPTE::Time smpte;
@@ -1030,7 +1035,7 @@ Session::deliver_mmc (MIDI::MachineControl::Command cmd, jack_nframes_t where)
 
 	mmc_buffer[nbytes++] = cmd;
 
-	// cerr << "delivering MMC, cmd = " << hex << (int) cmd << dec << endl;
+	cerr << "delivering MMC, cmd = " << hex << (int) cmd << dec << endl;
 	
 	switch (cmd) {
 	case MachineControl::cmdLocate:
@@ -1050,6 +1055,7 @@ Session::deliver_mmc (MIDI::MachineControl::Command cmd, jack_nframes_t where)
 
 	case MachineControl::cmdPlay:
 		/* always convert Play into Deferred Play */
+		/* Why? [DR] */
 		mmc_buffer[4] = MachineControl::cmdDeferredPlay;
 		break;
 
@@ -1073,14 +1079,13 @@ Session::deliver_mmc (MIDI::MachineControl::Command cmd, jack_nframes_t where)
 
 		mmc_buffer[nbytes++] = 0xf7; // terminate SysEx/MMC message
 
-		Glib::Mutex::Lock lm (midi_lock);
+		//Glib::Mutex::Lock lm (midi_lock);
 		
-		if (_mmc_port->write (mmc_buffer, nbytes) != nbytes) {
+		// FIXME: timestamp correct? [DR]
+		if (_mmc_port->write (mmc_buffer, nbytes, where - _transport_frame) != nbytes) {
 			error << string_compose(_("MMC: cannot send command %1%2%3"), &hex, cmd, &dec) << endmsg;
 		}
 	}
-#endif
-	cout << "MMC support broken." << endl;
 }
 
 bool
diff --git a/libs/ardour/session_process.cc b/libs/ardour/session_process.cc
index 411c749ade..daa3a1d380 100644
--- a/libs/ardour/session_process.cc
+++ b/libs/ardour/session_process.cc
@@ -30,7 +30,7 @@
 #include <ardour/ardour.h>
 #include <ardour/session.h>
 #include <ardour/timestamps.h>
-#include <ardour/diskstream.h>
+#include <ardour/audio_diskstream.h>
 #include <ardour/audioengine.h>
 #include <ardour/slave.h>
 #include <ardour/auditioner.h>
@@ -74,7 +74,7 @@ Session::process (jack_nframes_t nframes)
 void
 Session::prepare_diskstreams ()
 {
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		(*i)->prepare ();
 	}
 }
@@ -146,12 +146,12 @@ Session::process_routes (jack_nframes_t nframes, jack_nframes_t offset)
 
 		if ((ret = (*i)->roll (nframes, _transport_frame, _transport_frame + nframes, offset, declick, record_active, rec_monitors)) < 0) {
 
-			/* we have to do this here. Route::roll() for an AudioTrack will have called DiskStream::process(),
-			   and the DS will expect DiskStream::commit() to be called. but we're aborting from that
+			/* we have to do this here. Route::roll() for an AudioTrack will have called AudioDiskstream::process(),
+			   and the DS will expect AudioDiskstream::commit() to be called. but we're aborting from that
 			   call path, so make sure we release any outstanding locks here before we return failure.
 			*/
 
-			for (DiskStreamList::iterator ids = diskstreams.begin(); ids != diskstreams.end(); ++ids) {
+			for (AudioDiskstreamList::iterator ids = audio_diskstreams.begin(); ids != audio_diskstreams.end(); ++ids) {
 				(*ids)->recover ();
 			}
 
@@ -185,12 +185,12 @@ Session::silent_process_routes (jack_nframes_t nframes, jack_nframes_t offset)
 
 		if ((ret = (*i)->silent_roll (nframes, _transport_frame, _transport_frame + nframes, offset, record_active, rec_monitors)) < 0) {
 			
-			/* we have to do this here. Route::roll() for an AudioTrack will have called DiskStream::process(),
-			   and the DS will expect DiskStream::commit() to be called. but we're aborting from that
+			/* we have to do this here. Route::roll() for an AudioTrack will have called AudioDiskstream::process(),
+			   and the DS will expect AudioDiskstream::commit() to be called. but we're aborting from that
 			   call path, so make sure we release any outstanding locks here before we return failure.
 			*/
 
-			for (DiskStreamList::iterator ids = diskstreams.begin(); ids != diskstreams.end(); ++ids) {
+			for (AudioDiskstreamList::iterator ids = audio_diskstreams.begin(); ids != audio_diskstreams.end(); ++ids) {
 				(*ids)->recover ();
 			}
 
@@ -209,7 +209,7 @@ Session::commit_diskstreams (jack_nframes_t nframes, bool &needs_butler)
 	float pworst = 1.0f;
 	float cworst = 1.0f;
 
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 
 		if ((*i)->hidden()) {
 			continue;
@@ -579,7 +579,7 @@ Session::follow_slave (jack_nframes_t nframes, jack_nframes_t offset)
 				bool ok = true;
 				jack_nframes_t frame_delta = slave_transport_frame - _transport_frame;
 				
-				for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+				for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 					if (!(*i)->can_internal_playback_seek (frame_delta)) {
 						ok = false;
 						break;
@@ -587,7 +587,7 @@ Session::follow_slave (jack_nframes_t nframes, jack_nframes_t offset)
 				}
 
 				if (ok) {
-					for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+					for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 						(*i)->internal_playback_seek (frame_delta);
 					}
 					_transport_frame += frame_delta;
diff --git a/libs/ardour/session_state.cc b/libs/ardour/session_state.cc
index 466a546aee..edcc52d729 100644
--- a/libs/ardour/session_state.cc
+++ b/libs/ardour/session_state.cc
@@ -58,13 +58,11 @@
 #include <ardour/audioengine.h>
 #include <ardour/configuration.h>
 #include <ardour/session.h>
-#include <ardour/diskstream.h>
+#include <ardour/audio_diskstream.h>
 #include <ardour/utils.h>
 #include <ardour/audioplaylist.h>
-#include <ardour/source.h>
-#include <ardour/filesource.h>
+#include <ardour/audiofilesource.h>
 #include <ardour/destructive_filesource.h>
-#include <ardour/sndfilesource.h>
 #include <ardour/sndfile_helpers.h>
 #include <ardour/auditioner.h>
 #include <ardour/export.h>
@@ -196,12 +194,13 @@ Session::first_stage_init (string fullpath, string snapshot_name)
 	destructive_index = 0;
 
 	/* allocate conversion buffers */
-	_conversion_buffers[ButlerContext] = new char[DiskStream::disk_io_frames() * 4];
-	_conversion_buffers[TransportContext] = new char[DiskStream::disk_io_frames() * 4];
+	_conversion_buffers[ButlerContext] = new char[AudioDiskstream::disk_io_frames() * 4];
+	_conversion_buffers[TransportContext] = new char[AudioDiskstream::disk_io_frames() * 4];
 	
 	/* default short fade = 15ms */
 
 	Crossfade::set_short_xfade_length ((jack_nframes_t) floor ((15.0 * frame_rate()) / 1000.0));
+	DestructiveFileSource::setup_standard_crossfades (frame_rate());
 
 	last_mmc_step.tv_sec = 0;
 	last_mmc_step.tv_usec = 0;
@@ -267,10 +266,10 @@ Session::first_stage_init (string fullpath, string snapshot_name)
 	/* These are all static "per-class" signals */
 
 	Region::CheckNewRegion.connect (mem_fun (*this, &Session::add_region));
-	Source::SourceCreated.connect (mem_fun (*this, &Session::add_source));
+	AudioSource::AudioSourceCreated.connect (mem_fun (*this, &Session::add_audio_source));
 	Playlist::PlaylistCreated.connect (mem_fun (*this, &Session::add_playlist));
 	Redirect::RedirectCreated.connect (mem_fun (*this, &Session::add_redirect));
-	DiskStream::DiskStreamCreated.connect (mem_fun (*this, &Session::add_diskstream));
+	AudioDiskstream::AudioDiskstreamCreated.connect (mem_fun (*this, &Session::add_diskstream));
 	NamedSelection::NamedSelectionCreated.connect (mem_fun (*this, &Session::add_named_selection));
 
 	IO::MoreOutputs.connect (mem_fun (*this, &Session::ensure_passthru_buffers));
@@ -285,7 +284,7 @@ Session::first_stage_init (string fullpath, string snapshot_name)
 int
 Session::second_stage_init (bool new_session)
 {
-	ExternalSource::set_peak_dir (peak_dir());
+	AudioFileSource::set_peak_dir (peak_dir());
 
 	if (!new_session) {
 		if (load_state (_current_snapshot_name)) {
@@ -425,7 +424,7 @@ Session::setup_raid_path (string path)
 		}
 		fspath += tape_dir_name;
 		
-		FileSource::set_search_path (fspath);
+		AudioFileSource::set_search_path (fspath);
 
 		return;
 	}
@@ -481,9 +480,9 @@ Session::setup_raid_path (string path)
 		session_dirs.push_back (sp);
 	}
 
-	/* set the FileSource search path */
+	/* set the AudioFileSource search path */
 
-	FileSource::set_search_path (fspath);
+	AudioFileSource::set_search_path (fspath);
 
 	/* reset the round-robin soundfile path thingie */
 
@@ -625,11 +624,11 @@ Session::load_diskstreams (const XMLNode& node)
 
 	for (citer = clist.begin(); citer != clist.end(); ++citer) {
 		
-		DiskStream* dstream;
+		AudioDiskstream* dstream;
 
 		try {
-			dstream = new DiskStream (*this, **citer);
-			/* added automatically by DiskStreamCreated handler */
+			dstream = new AudioDiskstream (*this, **citer);
+			/* added automatically by AudioDiskstreamCreated handler */
 		} 
 		
 		catch (failed_constructor& err) {
@@ -1335,15 +1334,15 @@ Session::state(bool full_state)
 	child = node->add_child ("Sources");
 
 	if (full_state) {
-		Glib::Mutex::Lock sl (source_lock);
+		Glib::Mutex::Lock sl (audio_source_lock);
 
-		for (SourceList::iterator siter = sources.begin(); siter != sources.end(); ++siter) {
+		for (AudioSourceList::iterator siter = audio_sources.begin(); siter != audio_sources.end(); ++siter) {
 			
-			/* Don't save information about FileSources that are empty */
+			/* Don't save information about AudioFileSources that are empty */
 			
-			FileSource* fs;
+			AudioFileSource* fs;
 
-			if ((fs = dynamic_cast<FileSource*> ((*siter).second)) != 0) {
+			if ((fs = dynamic_cast<AudioFileSource*> ((*siter).second)) != 0) {
 				DestructiveFileSource* dfs = dynamic_cast<DestructiveFileSource*> (fs);
 
 				/* destructive file sources are OK if they are empty, because
@@ -1380,7 +1379,7 @@ Session::state(bool full_state)
 
 	{ 
 		Glib::RWLock::ReaderLock dl (diskstream_lock);
-		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 			if (!(*i)->hidden()) {
 				child->add_child_nocopy ((*i)->get_state());
 			}
@@ -1511,7 +1510,7 @@ Session::set_state (const XMLNode& node)
 	Options
 	Sources
 	AudioRegions
-	DiskStreams
+	AudioDiskstreams
 	Connections
 	Locations
 	Routes
@@ -1745,6 +1744,7 @@ Session::XMLRegionFactory (const XMLNode& node, bool full)
 	const XMLProperty* prop;
 	id_t s_id;
 	Source* source;
+	AudioSource* as;
 	AudioRegion::SourceList sources;
 	uint32_t nchans = 1;
 	char buf[128];
@@ -1772,7 +1772,13 @@ Session::XMLRegionFactory (const XMLNode& node, bool full)
 		return 0;
 	}
 
-	sources.push_back(source);
+	as = dynamic_cast<AudioSource*>(source);
+	if (!as) {
+		error << string_compose(_("Session: XMLNode describing a AudioRegion references a non-audio source id =%1"), s_id) << endmsg;
+		return 0;
+	}
+
+	sources.push_back (as);
 
 	/* pickup other channels */
 
@@ -1785,7 +1791,13 @@ Session::XMLRegionFactory (const XMLNode& node, bool full)
 				error << string_compose(_("Session: XMLNode describing a AudioRegion references an unknown source id =%1"), s_id) << endmsg;
 				return 0;
 			}
-			sources.push_back(source);
+			
+			as = dynamic_cast<AudioSource*>(source);
+			if (!as) {
+				error << string_compose(_("Session: XMLNode describing a AudioRegion references a non-audio source id =%1"), s_id) << endmsg;
+				return 0;
+			}
+			sources.push_back (as);
 		}
 	}
 	
@@ -1804,12 +1816,14 @@ Session::get_sources_as_xml ()
 
 {
 	XMLNode* node = new XMLNode (X_("Sources"));
-	Glib::Mutex::Lock lm (source_lock);
+	Glib::Mutex::Lock lm (audio_source_lock);
 
-	for (SourceList::iterator i = sources.begin(); i != sources.end(); ++i) {
+	for (AudioSourceList::iterator i = audio_sources.begin(); i != audio_sources.end(); ++i) {
 		node->add_child_nocopy ((*i).second->get_state());
 	}
 
+	/* XXX get MIDI and other sources here */
+
 	return *node;
 }
 
@@ -1867,23 +1881,12 @@ Session::XMLSourceFactory (const XMLNode& node)
 	}
 
 	try {
-		if (node.property (X_("destructive")) != 0) {
-			src = new DestructiveFileSource (node, frame_rate());
-		} else {
-			src = new FileSource (node, frame_rate());
-		}
+		src = AudioFileSource::create (node);
 	}
 	
 	catch (failed_constructor& err) {
-
-		try {
-			src = ExternalSource::create (node);
-		}
-
-		catch (failed_constructor& err) {
-			error << _("Found a sound file that cannot be used by Ardour. See the progammers.") << endmsg;
-			return 0;
-		} 
+		error << _("Found a sound file that cannot be used by Ardour. Talk to the progammers.") << endmsg;
+		return 0;
 	}
 
 	return src;
@@ -2930,9 +2933,9 @@ Session::cleanup_sources (Session::cleanup_report& rep)
 	rep.paths.clear ();
 	rep.space = 0;
 
-	for (SourceList::iterator i = sources.begin(); i != sources.end(); ) {
+	for (AudioSourceList::iterator i = audio_sources.begin(); i != audio_sources.end(); ) {
 
-		SourceList::iterator tmp;
+		AudioSourceList::iterator tmp;
 
 		tmp = i;
 		++tmp;
@@ -2949,7 +2952,7 @@ Session::cleanup_sources (Session::cleanup_report& rep)
 			   adding it to the list of all sources below
 			*/
 
-			sources.erase (i);
+			audio_sources.erase (i);
 		}
 
 		i = tmp;
@@ -3013,20 +3016,17 @@ Session::cleanup_sources (Session::cleanup_report& rep)
 	   state file on disk still references sources we may have already
 	   dropped.
 	*/
-
+	
 	find_all_sources_across_snapshots (all_sources, true);
 
-	/* add our current source list
+	/*  add our current source list
 	 */
-
-	for (SourceList::iterator i = sources.begin(); i != sources.end(); ++i) {
-		FileSource* fs;
-		ExternalSource* sfs;
+	
+	for (AudioSourceList::iterator i = audio_sources.begin(); i != audio_sources.end(); ++i) {
+		AudioFileSource* fs;
 		
-		if ((fs = dynamic_cast<FileSource*> ((*i).second)) != 0) {
+		if ((fs = dynamic_cast<AudioFileSource*> ((*i).second)) != 0) {
 			all_sources.insert (fs->path());
-		} else if ((sfs = dynamic_cast<ExternalSource*> ((*i).second)) != 0) {
-			all_sources.insert (sfs->path());
 		} 
 	}
 
diff --git a/libs/ardour/session_time.cc b/libs/ardour/session_time.cc
index 453f5d6d27..d597860a5e 100644
--- a/libs/ardour/session_time.cc
+++ b/libs/ardour/session_time.cc
@@ -32,6 +32,7 @@
 #include <ardour/audioengine.h>
 #include <ardour/session.h>
 #include <ardour/tempo.h>
+#include <ardour/audiofilesource.h>
 
 #include "i18n.h"
 
@@ -95,6 +96,9 @@ Session::set_smpte_offset (jack_nframes_t off)
 {
 	_smpte_offset = off;
 	last_smpte_valid = false;
+
+	AudioFileSource::set_header_position_offset (_smpte_offset, _smpte_offset_negative);
+
 	SMPTEOffsetChanged (); /* EMIT SIGNAL */
 }
 
@@ -103,6 +107,9 @@ Session::set_smpte_offset_negative (bool neg)
 {
 	_smpte_offset_negative = neg;
 	last_smpte_valid = false;
+
+	AudioFileSource::set_header_position_offset (_smpte_offset, _smpte_offset_negative);
+
 	SMPTEOffsetChanged (); /* EMIT SIGNAL */
 }
 
@@ -194,7 +201,7 @@ void
 Session::sample_to_smpte( jack_nframes_t sample, SMPTE::Time& smpte, bool use_offset, bool use_subframes ) const
 {
 	jack_nframes_t offset_sample;
-  
+
 	if (!use_offset) {
 		offset_sample = sample;
 		smpte.negative = false;
@@ -326,7 +333,7 @@ Session::smpte_duration_string (char* buf, jack_nframes_t when) const
 	SMPTE::Time smpte;
 
 	smpte_duration (when, smpte);
-	snprintf (buf, sizeof (buf), "%02ld:%02ld:%02ld:%02ld", smpte.hours, smpte.minutes, smpte.seconds, smpte.frames);
+	snprintf (buf, sizeof (buf), "%02" PRIu32 ":%02" PRIu32 ":%02" PRIu32 ":%02" PRIu32, smpte.hours, smpte.minutes, smpte.seconds, smpte.frames);
 }
 
 void
diff --git a/libs/ardour/session_timefx.cc b/libs/ardour/session_timefx.cc
index 6351aa9825..ee751b9af7 100644
--- a/libs/ardour/session_timefx.cc
+++ b/libs/ardour/session_timefx.cc
@@ -27,7 +27,6 @@
 
 #include <ardour/session.h>
 #include <ardour/audioregion.h>
-#include <ardour/filesource.h>
 #include <ardour/sndfilesource.h>
 
 #include "i18n.h"
@@ -80,7 +79,10 @@ Session::tempoize_region (TimeStretchRequest& tsr)
 		}
 
 		try {
-			sources.push_back(new FileSource (path, frame_rate(), false, Config->get_native_file_data_format()));
+			sources.push_back (new SndFileSource (path, 
+							      Config->get_native_file_data_format(),
+							      Config->get_native_file_header_format(),
+							      frame_rate()));
 		} catch (failed_constructor& err) {
 			error << string_compose (_("tempoize: error creating new audio file %1 (%2)"), path, strerror (errno)) << endmsg;
 			goto out;
@@ -150,13 +152,16 @@ Session::tempoize_region (TimeStretchRequest& tsr)
 	xnow = localtime (&now);
 
 	for (it = sources.begin(); it != sources.end(); ++it) {
-		dynamic_cast<FileSource*>(*it)->update_header (tsr.region->position(), *xnow, now);
+		AudioFileSource* afs = dynamic_cast<AudioFileSource*>(*it);
+		if (afs) {
+			afs->update_header (tsr.region->position(), *xnow, now);
+		}
 	}
 
 	region_name = tsr.region->name() + X_(".t");
 
 	r = new AudioRegion (sources, 0, sources.front()->length(), region_name,
-			0, AudioRegion::Flag (AudioRegion::DefaultFlags | AudioRegion::WholeFile));
+			     0, AudioRegion::Flag (AudioRegion::DefaultFlags | AudioRegion::WholeFile));
 
 
   out:
diff --git a/libs/ardour/session_transport.cc b/libs/ardour/session_transport.cc
index fafaf2a475..c05f8f4054 100644
--- a/libs/ardour/session_transport.cc
+++ b/libs/ardour/session_transport.cc
@@ -36,7 +36,7 @@
 #include <ardour/ardour.h>
 #include <ardour/audioengine.h>
 #include <ardour/session.h>
-#include <ardour/diskstream.h>
+#include <ardour/audio_diskstream.h>
 #include <ardour/auditioner.h>
 #include <ardour/slave.h>
 #include <ardour/location.h>
@@ -78,7 +78,7 @@ Session::request_transport_speed (float speed)
 }
 
 void
-Session::request_diskstream_speed (DiskStream& ds, float speed)
+Session::request_diskstream_speed (AudioDiskstream& ds, float speed)
 {
 	Event* ev = new Event (Event::SetDiskstreamSpeed, Event::Add, Event::Immediate, 0, speed);
 	ev->set_ptr (&ds);
@@ -200,7 +200,7 @@ Session::butler_transport_work ()
 	}
 
 	if (post_transport_work & PostTransportInputChange) {
-		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 			(*i)->non_realtime_input_change ();
 		}
 	}
@@ -216,7 +216,7 @@ Session::butler_transport_work ()
 		cumulative_rf_motion = 0;
 		reset_rf_scale (0);
 
-		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 			if (!(*i)->hidden()) {
 				if ((*i)->speed() != 1.0f || (*i)->speed() != -1.0f) {
 					(*i)->seek ((jack_nframes_t) (_transport_frame * (double) (*i)->speed()));
@@ -248,7 +248,7 @@ Session::non_realtime_set_speed ()
 {
 	Glib::RWLock::ReaderLock lm (diskstream_lock);
 
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		(*i)->non_realtime_set_speed ();
 	}
 }
@@ -258,7 +258,7 @@ Session::non_realtime_overwrite ()
 {
 	Glib::RWLock::ReaderLock lm (diskstream_lock);
 
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		if ((*i)->pending_overwrite) {
 			(*i)->overwrite_existing_buffers ();
 		}
@@ -274,7 +274,7 @@ Session::non_realtime_stop (bool abort)
 	
 	did_record = false;
 	
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		if ((*i)->get_captured_frames () != 0) {
 			did_record = true;
 			break;
@@ -327,7 +327,7 @@ Session::non_realtime_stop (bool abort)
 		_have_captured = true;
 	}
 
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		(*i)->transport_stopped (*now, xnow, abort);
 	}
 	
@@ -364,7 +364,7 @@ Session::non_realtime_stop (bool abort)
 	}
 #endif
 
-		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 			if (!(*i)->hidden()) {
 				if ((*i)->speed() != 1.0f || (*i)->speed() != -1.0f) {
 					(*i)->seek ((jack_nframes_t) (_transport_frame * (double) (*i)->speed()));
@@ -494,7 +494,7 @@ Session::set_auto_loop (bool yn)
 
 			if (seamless_loop) {
 				// set all diskstreams to use internal looping
-				for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+				for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 					if (!(*i)->hidden()) {
 						(*i)->set_loop (loc);
 					}
@@ -502,7 +502,7 @@ Session::set_auto_loop (bool yn)
 			}
 			else {
 				// set all diskstreams to NOT use internal looping
-				for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+				for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 					if (!(*i)->hidden()) {
 						(*i)->set_loop (0);
 					}
@@ -532,7 +532,7 @@ Session::set_auto_loop (bool yn)
 		clear_events (Event::AutoLoop);
 
 		// set all diskstreams to NOT use internal looping
-		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 			if (!(*i)->hidden()) {
 				(*i)->set_loop (0);
 			}
@@ -653,7 +653,7 @@ Session::locate (jack_nframes_t target_frame, bool with_roll, bool with_flush, b
 			   The rarity and short potential lock duration makes this "OK"
 			*/
 			Glib::RWLock::ReaderLock dsm (diskstream_lock);
-			for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+			for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
 					//cerr << "switching from input" << __FILE__ << __LINE__ << endl << endl;
 					(*i)->monitor_input (!auto_input);
@@ -668,7 +668,7 @@ Session::locate (jack_nframes_t target_frame, bool with_roll, bool with_flush, b
 			   The rarity and short potential lock duration makes this "OK"
 			*/
 			Glib::RWLock::ReaderLock dsm (diskstream_lock);
-			for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+			for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
 					//cerr << "switching to input" << __FILE__ << __LINE__ << endl << endl;
 					(*i)->monitor_input (true);
@@ -714,7 +714,7 @@ Session::set_transport_speed (float speed, bool abort)
 			   The rarity and short potential lock duration makes this "OK"
 			*/
 			Glib::RWLock::ReaderLock dsm (diskstream_lock);
-			for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+			for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
 					//cerr << "switching to input" << __FILE__ << __LINE__ << endl << endl;
 					(*i)->monitor_input (true);	
@@ -740,7 +740,7 @@ Session::set_transport_speed (float speed, bool abort)
 			   The rarity and short potential lock duration makes this "OK"
 			*/
 			Glib::RWLock::ReaderLock dsm (diskstream_lock);
-			for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+			for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 				if (auto_input && (*i)->record_enabled ()) {
 					//cerr << "switching from input" << __FILE__ << __LINE__ << endl << endl;
 					(*i)->monitor_input (false);	
@@ -791,7 +791,7 @@ Session::set_transport_speed (float speed, bool abort)
 		_last_transport_speed = _transport_speed;
 		_transport_speed = speed;
 		
-		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+		for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 			if ((*i)->realtime_set_speed ((*i)->speed(), true)) {
 				post_transport_work = PostTransportWork (post_transport_work | PostTransportSpeed);
 			}
@@ -881,7 +881,7 @@ Session::actually_start_transport ()
 	transport_sub_state |= PendingDeclickIn;
 	_transport_speed = 1.0;
 	
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		(*i)->realtime_set_speed ((*i)->speed(), true);
 	}
 
@@ -1016,7 +1016,7 @@ Session::set_slave_source (SlaveSource src, jack_nframes_t frame)
 	
 	_slave_type = src;
 
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		if (!(*i)->hidden()) {
 			if ((*i)->realtime_set_speed ((*i)->speed(), true)) {
 				non_rt_required = true;
@@ -1048,7 +1048,7 @@ Session::reverse_diskstream_buffers ()
 }
 
 void
-Session::set_diskstream_speed (DiskStream* stream, float speed)
+Session::set_diskstream_speed (AudioDiskstream* stream, float speed)
 {
 	if (stream->realtime_set_speed (speed, false)) {
 		post_transport_work = PostTransportWork (post_transport_work | PostTransportSpeed);
@@ -1244,7 +1244,7 @@ Session::update_latency_compensation (bool with_stop, bool abort)
 	/* reflect any changes in latencies into capture offsets
 	*/
 	
-	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
+	for (AudioDiskstreamList::iterator i = audio_diskstreams.begin(); i != audio_diskstreams.end(); ++i) {
 		(*i)->set_capture_offset ();
 	}
 }
diff --git a/libs/ardour/sndfilesource.cc b/libs/ardour/sndfilesource.cc
index 87f7faf423..6929385141 100644
--- a/libs/ardour/sndfilesource.cc
+++ b/libs/ardour/sndfilesource.cc
@@ -18,47 +18,203 @@
     $Id$
 */
 
+#include <cerrno>
+#include <climits>
+
+#include <pwd.h>
+#include <sys/utsname.h>
+
+#include <glibmm/miscutils.h>
+
 #include <ardour/sndfilesource.h>
 
 #include "i18n.h"
 
+using namespace std;
 using namespace ARDOUR;
 
 SndFileSource::SndFileSource (const XMLNode& node)
-	: ExternalSource (node)
+	: AudioFileSource (node)
 {
-	init (_name, true);
-	SourceCreated (this); /* EMIT SIGNAL */
+	init (_name);
+
+	if (open()) {
+		throw failed_constructor ();
+	}
+
+	if (_build_peakfiles) {
+		if (initialize_peakfile (false, _path)) {
+			sf_close (sf);
+			sf = 0;
+			throw failed_constructor ();
+		}
+	}
+
+	AudioSourceCreated (this); /* EMIT SIGNAL */
 }
 
-SndFileSource::SndFileSource (const string& idstr, bool build_peak)
-	: ExternalSource(idstr, build_peak)
+SndFileSource::SndFileSource (string idstr, Flag flags)
+	: AudioFileSource (idstr, Flag (flags & ~(Writable|Removable|RemovableIfEmpty|RemoveAtDestroy)))
 {
-	init (idstr, build_peak);
+	init (idstr);
 
-	if (build_peak) {
-		 SourceCreated (this); /* EMIT SIGNAL */
+	if (open()) {
+		throw failed_constructor ();
 	}
+
+	if (_build_peakfiles) {
+		if (initialize_peakfile (false, _path)) {
+			sf_close (sf);
+			sf = 0;
+			throw failed_constructor ();
+		}
+	}
+
+
+	AudioSourceCreated (this); /* EMIT SIGNAL */
+}
+
+SndFileSource::SndFileSource (string idstr, SampleFormat sfmt, HeaderFormat hf, jack_nframes_t rate, Flag flags)
+	: AudioFileSource(idstr, flags, sfmt, hf)
+{
+	int fmt = 0;
+
+	init (idstr);
+
+	cerr << "creating " << idstr << " hf = " << hf << endl;
+
+	switch (hf) {
+	case CAF:
+		fmt = SF_FORMAT_CAF;
+		_flags = Flag (_flags & ~Broadcast);
+		break;
+
+	case AIFF:
+		fmt = SF_FORMAT_AIFF;
+		_flags = Flag (_flags & ~Broadcast);
+		break;
+
+	case BWF:
+		fmt = SF_FORMAT_WAV;
+		_flags = Flag (_flags | Broadcast);
+		break;
+
+	case WAVE:
+		fmt = SF_FORMAT_WAV;
+		_flags = Flag (_flags & ~Broadcast);
+		break;
+
+	case WAVE64:
+		fmt = SF_FORMAT_W64;
+		_flags = Flag (_flags & ~Broadcast);
+		break;
+
+	default:
+		fatal << string_compose (_("programming error: %1"), X_("unsupported audio header format requested")) << endmsg;
+		/*NOTREACHED*/
+		break;
+
+	}
+
+	switch (sfmt) {
+	case FormatFloat:
+		fmt |= SF_FORMAT_FLOAT;
+		break;
+
+	case FormatInt24:
+		fmt |= SF_FORMAT_PCM_24;
+		break;
+	}
+	
+	_info.channels = 1;
+	_info.samplerate = rate;
+	_info.format = fmt;
+
+	if (open()) {
+		throw failed_constructor();
+	}
+
+	if (writable() && (_flags & Broadcast)) {
+
+		_broadcast_info = new SF_BROADCAST_INFO;
+		memset (_broadcast_info, 0, sizeof (*_broadcast_info));
+		
+		snprintf (_broadcast_info->description, sizeof (_broadcast_info->description), "BWF %s", _name.c_str());
+		
+		struct utsname utsinfo;
+
+		if (uname (&utsinfo)) {
+			error << string_compose(_("FileSource: cannot get host information for BWF header (%1)"), strerror(errno)) << endmsg;
+			return;
+		}
+		
+		snprintf (_broadcast_info->originator, sizeof (_broadcast_info->originator), "ardour:%s:%s:%s:%s:%s)", 
+			  Glib::get_real_name().c_str(),
+			  utsinfo.nodename,
+			  utsinfo.sysname,
+			  utsinfo.release,
+			  utsinfo.version);
+		
+		_broadcast_info->version = 1;  
+		
+		/* XXX do something about this field */
+		
+		snprintf (_broadcast_info->umid, sizeof (_broadcast_info->umid), "%s", "fnord");
+		
+		/* coding history is added by libsndfile */
+
+		if (sf_command (sf, SFC_SET_BROADCAST_INFO, _broadcast_info, sizeof (_broadcast_info)) != SF_TRUE) {
+			char errbuf[256];
+			sf_error_str (0, errbuf, sizeof (errbuf) - 1);
+			error << string_compose (_("cannot set broadcast info for audio file %1 (%2); dropping broadcast info for this file"), _path, errbuf) << endmsg;
+			_flags = Flag (_flags & ~Broadcast);
+			delete _broadcast_info;
+			_broadcast_info = 0;
+		}
+	}
+	
+	if (_build_peakfiles) {
+		if (initialize_peakfile (false, _path)) {
+			sf_close (sf);
+			sf = 0;
+			throw failed_constructor ();
+		}
+	}
+
+	/* since SndFileSource's constructed with this constructor can be writable, make sure we update if the header info changes */
+
+	if (writable()) {
+		HeaderPositionOffsetChanged.connect (mem_fun (*this, &AudioFileSource::handle_header_position_change));
+	}
+
+	if (_build_peakfiles) {
+		if (initialize_peakfile (false, _path)) {
+			sf_close (sf);
+			sf = 0;
+			throw failed_constructor ();
+		}
+	}
+
+	AudioSourceCreated (this); /* EMIT SIGNAL */
 }
 
 void 
-SndFileSource::init (const string& idstr, bool build_peak)
+SndFileSource::init (const string& idstr)
 {
 	string::size_type pos;
 	string file;
 
-	tmpbuf = 0;
-	tmpbufsize = 0;
+	interleave_buf = 0;
+	interleave_bufsize = 0;
 	sf = 0;
-
-	_name = idstr;
+	_broadcast_info = 0;
 
 	if ((pos = idstr.find_last_of (':')) == string::npos) {
 		channel = 0;
-		file = idstr;
+		_name = Glib::path_get_basename (idstr);
 	} else {
 		channel = atoi (idstr.substr (pos+1).c_str());
-		file = idstr.substr (0, pos);
+		_name = Glib::path_get_basename (idstr.substr (0, pos));
 	}
 
 	/* although libsndfile says we don't need to set this,
@@ -66,46 +222,56 @@ SndFileSource::init (const string& idstr, bool build_peak)
 	*/
 
 	memset (&_info, 0, sizeof(_info));
+}
 
-	/* note that we temporarily truncated _id at the colon */
-	
-	if ((sf = sf_open (file.c_str(), SFM_READ, &_info)) == 0) {
+int
+SndFileSource::open ()
+{
+	if ((sf = sf_open (_path.c_str(), (writable() ? SFM_RDWR : SFM_READ), &_info)) == 0) {
 		char errbuf[256];
 		sf_error_str (0, errbuf, sizeof (errbuf) - 1);
-		error << string_compose(_("SndFileSource: cannot open file \"%1\" (%2)"), file, errbuf) << endmsg;
-		throw failed_constructor();
+		error << string_compose(_("SndFileSource: cannot open file \"%1\" for %2 (%3)"), 
+					_path, (writable() ? "read+write" : "reading"), errbuf) << endmsg;
+		return -1;
 	}
 
 	if (channel >= _info.channels) {
 		error << string_compose(_("SndFileSource: file only contains %1 channels; %2 is invalid as a channel number"), _info.channels, channel) << endmsg;
 		sf_close (sf);
 		sf = 0;
-		throw failed_constructor();
+		return -1;
 	}
 
 	_length = _info.frames;
-	_path = file;
 
-	if (build_peak) {
-		if (initialize_peakfile (false, _path)) {
-			sf_close (sf);
-			sf = 0;
-			throw failed_constructor ();
-		}
+	if (writable()) {
+		sf_command (sf, SFC_SET_UPDATE_HEADER_AUTO, 0, SF_FALSE);
+	}
+
+	return 0;
+}
+
+void
+SndFileSource::close ()
+{
+	if (sf) {
+		sf_close (sf);
+		sf = 0;
 	}
 }
 
 SndFileSource::~SndFileSource ()
-
 {
 	GoingAway (this); /* EMIT SIGNAL */
 
-	if (sf) {
-		sf_close (sf);
+	close ();
+
+	if (interleave_buf) {
+		delete [] interleave_buf;
 	}
 
-	if (tmpbuf) {
-		delete [] tmpbuf;
+	if (_broadcast_info) {
+		delete [] _broadcast_info;
 	}
 }
 
@@ -116,49 +282,73 @@ SndFileSource::sample_rate () const
 }
 
 jack_nframes_t
-SndFileSource::read (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const
+SndFileSource::read_unlocked (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const
 {
 	int32_t nread;
 	float *ptr;
 	uint32_t real_cnt;
+	jack_nframes_t file_cnt;
 
-	if (sf_seek (sf, (off_t) start, SEEK_SET) < 0) {
-		char errbuf[256];
-		sf_error_str (0, errbuf, sizeof (errbuf) - 1);
-		error << string_compose(_("SndFileSource: could not seek to frame %1 within %2 (%3)"), start, _name.substr (1), errbuf) << endmsg;
-		return 0;
-	}
+	if (start > _length) {
 
-	if (_info.channels == 1) {
-		jack_nframes_t ret = sf_read_float (sf, dst, cnt);
-		_read_data_count = cnt * sizeof(float);
-		return ret;
-	}
+		/* read starts beyond end of data, just memset to zero */
+		
+		file_cnt = 0;
 
-	real_cnt = cnt * _info.channels;
+	} else if (start + cnt > _length) {
+		
+		/* read ends beyond end of data, read some, memset the rest */
+		
+		file_cnt = _length - start;
 
-	{
-		Glib::Mutex::Lock lm (_tmpbuf_lock);
+	} else {
 		
-		if (tmpbufsize < real_cnt) {
-			
-			if (tmpbuf) {
-				delete [] tmpbuf;
-			}
-			tmpbufsize = real_cnt;
-			tmpbuf = new float[tmpbufsize];
+		/* read is entirely within data */
+
+		file_cnt = cnt;
+	}
+	
+	if (file_cnt) {
+
+		if (sf_seek (sf, (off_t) start, SEEK_SET) < 0) {
+			char errbuf[256];
+			sf_error_str (0, errbuf, sizeof (errbuf) - 1);
+			error << string_compose(_("SndFileSource: could not seek to frame %1 within %2 (%3)"), start, _name.substr (1), errbuf) << endmsg;
+			return 0;
 		}
 		
-		nread = sf_read_float (sf, tmpbuf, real_cnt);
-		ptr = tmpbuf + channel;
-		nread /= _info.channels;
-		
-		/* stride through the interleaved data */
+		if (_info.channels == 1) {
+			jack_nframes_t ret = sf_read_float (sf, dst, file_cnt);
+			_read_data_count = cnt * sizeof(float);
+			return ret;
+		}
+	}
+
+	if (file_cnt != cnt) {
+		jack_nframes_t delta = cnt - file_cnt;
+		memset (dst+file_cnt, 0, sizeof (Sample) * delta);
+	}
+
+	real_cnt = cnt * _info.channels;
+
+	if (interleave_bufsize < real_cnt) {
 		
-		for (int32_t n = 0; n < nread; ++n) {
-			dst[n] = *ptr;
-			ptr += _info.channels;
+		if (interleave_buf) {
+			delete [] interleave_buf;
 		}
+		interleave_bufsize = real_cnt;
+		interleave_buf = new float[interleave_bufsize];
+	}
+	
+	nread = sf_read_float (sf, interleave_buf, real_cnt);
+	ptr = interleave_buf + channel;
+	nread /= _info.channels;
+	
+	/* stride through the interleaved data */
+	
+	for (int32_t n = 0; n < nread; ++n) {
+		dst[n] = *ptr;
+		ptr += _info.channels;
 	}
 
 	_read_data_count = cnt * sizeof(float);
@@ -166,3 +356,163 @@ SndFileSource::read (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char
 	return nread;
 }
 
+jack_nframes_t 
+SndFileSource::write_unlocked (Sample *data, jack_nframes_t cnt, char * workbuf)
+{
+	if (!writable()) {
+		return 0;
+	}
+
+	if (_info.channels != 1) {
+		fatal << string_compose (_("programming error: %1 %2"), X_("SndFileSource::write called on non-mono file"), _path) << endmsg;
+		/*NOTREACHED*/
+		return 0;
+	}
+	
+	jack_nframes_t oldlen;
+	int32_t frame_pos = _length;
+	
+	if (write_float (data, frame_pos, cnt) != cnt) {
+		return 0;
+	}
+
+	oldlen = _length;
+	update_length (oldlen, cnt);
+
+	if (_build_peakfiles) {
+		PeakBuildRecord *pbr = 0;
+		
+		if (pending_peak_builds.size()) {
+				pbr = pending_peak_builds.back();
+			}
+			
+			if (pbr && pbr->frame + pbr->cnt == oldlen) {
+				
+				/* the last PBR extended to the start of the current write,
+				   so just extend it again.
+				*/
+
+				pbr->cnt += cnt;
+			} else {
+				pending_peak_builds.push_back (new PeakBuildRecord (oldlen, cnt));
+			}
+			
+			_peaks_built = false;
+	}
+	
+	
+	if (_build_peakfiles) {
+		queue_for_peaks (*this);
+	}
+
+	_write_data_count = cnt;
+	
+	return cnt;
+}
+
+int
+SndFileSource::update_header (jack_nframes_t when, struct tm& now, time_t tnow)
+{	
+	/* allow derived classes to override how this is done */
+
+	set_timeline_position (when);
+
+	if (_flags & Broadcast) {
+		/* this will flush the header implicitly */
+		return setup_broadcast_info (when, now, tnow);
+	} else {
+		return flush_header ();
+	}
+}
+
+int
+SndFileSource::flush_header ()
+{
+	return (sf_command (sf, SFC_UPDATE_HEADER_NOW, 0, 0) != SF_TRUE);
+}
+
+int
+SndFileSource::setup_broadcast_info (jack_nframes_t when, struct tm& now, time_t tnow)
+{
+	/* random code is 9 digits */
+	
+	int random_code = random() % 999999999;
+	
+	snprintf (_broadcast_info->originator_reference, sizeof (_broadcast_info->originator_reference), "%2s%3s%12s%02d%02d%02d%9d",
+		  bwf_country_code,
+		  bwf_organization_code,
+		  bwf_serial_number,
+		  now.tm_hour,
+		  now.tm_min,
+		  now.tm_sec,
+		  random_code);
+	
+	snprintf (_broadcast_info->origination_date, sizeof (_broadcast_info->origination_date), "%4d-%02d-%02d",
+		  1900 + now.tm_year,
+		  now.tm_mon,
+		  now.tm_mday);
+	
+	snprintf (_broadcast_info->origination_time, sizeof (_broadcast_info->origination_time), "%02d-%02d-%02d",
+		  now.tm_hour,
+		  now.tm_min,
+		  now.tm_sec);
+
+	/* now update header position taking header offset into account */
+	
+	set_header_timeline_position ();
+
+	/* note that libsndfile flushes the header to disk when resetting the broadcast info */
+
+	if (sf_command (sf, SFC_SET_BROADCAST_INFO, _broadcast_info, sizeof (*_broadcast_info)) != SF_TRUE) {
+		error << string_compose (_("cannot set broadcast info for audio file %1; Dropping broadcast info for this file"), _path) << endmsg;
+		_flags = Flag (_flags & ~Broadcast);
+		delete _broadcast_info;
+		_broadcast_info = 0;
+		return -1;
+	}
+
+	return 0;
+}
+
+void
+SndFileSource::set_header_timeline_position ()
+{
+	uint64_t pos;
+
+	_broadcast_info->time_reference_high = 0;
+
+	if (header_position_negative) {
+
+		if (ULONG_LONG_MAX - header_position_offset < timeline_position) {
+			pos = ULONG_LONG_MAX; // impossible
+		} else {
+			pos = timeline_position + header_position_offset;
+		}
+
+	} else {
+
+		if (timeline_position < header_position_offset) {
+			pos = 0;
+		} else {
+			pos = timeline_position - header_position_offset;
+		}
+	}
+
+	_broadcast_info->time_reference_high = (pos >> 32);
+	_broadcast_info->time_reference_low = (pos & 0xffffffff);
+}
+
+jack_nframes_t
+SndFileSource::write_float (Sample* data, jack_nframes_t frame_pos, jack_nframes_t cnt)
+{
+	if (sf_seek (sf, frame_pos, SEEK_SET) != frame_pos) {
+		error << string_compose (_("%1: cannot seek to %2"), _path, frame_pos) << endmsg;
+		return 0;
+	}
+	
+	if (sf_writef_float (sf, data, cnt) != (ssize_t) cnt) {
+		return 0;
+	}
+	
+	return cnt;
+}
diff --git a/libs/ardour/source.cc b/libs/ardour/source.cc
index 7d790a036d..0d32ea4a21 100644
--- a/libs/ardour/source.cc
+++ b/libs/ardour/source.cc
@@ -42,35 +42,18 @@ using std::max;
 
 using namespace ARDOUR;
 
-sigc::signal<void,Source *>  Source::SourceCreated;
-pthread_t                    Source::peak_thread;
-bool                         Source::have_peak_thread = false;
-vector<Source*>              Source::pending_peak_sources;
-Glib::StaticMutex            Source::pending_peak_sources_lock = GLIBMM_STATIC_MUTEX_INIT;
-int                          Source::peak_request_pipe[2];
-
-bool Source::_build_missing_peakfiles = false;
-bool Source::_build_peakfiles = false;
-
-Source::Source (bool announce)
+Source::Source (string name)
 {
+	_name = name;
 	_id = ARDOUR::new_id();
 	_use_cnt = 0;
-	_peaks_built = false;
-	next_peak_clear_should_notify = true;
 	_timestamp = 0;
-	_read_data_count = 0;
-	_write_data_count = 0;
 }
 
 Source::Source (const XMLNode& node) 
 {
 	_use_cnt = 0;
-	_peaks_built = false;
-	next_peak_clear_should_notify = true;
 	_timestamp = 0;
-	_read_data_count = 0;
-	_write_data_count = 0;
 
 	if (set_state (node)) {
 		throw failed_constructor();
@@ -96,10 +79,6 @@ Source::get_state ()
 		node->add_property ("timestamp", buf);
 	}
 
-	if (_captured_for.length()) {
-		node->add_property ("captured-for", _captured_for);
-	}
-
 	return *node;
 }
 
@@ -124,735 +103,10 @@ Source::set_state (const XMLNode& node)
 		sscanf (prop->value().c_str(), "%ld", &_timestamp);
 	}
 
-	if ((prop = node.property ("captured-for")) != 0) {
-		_captured_for = prop->value();
-	}
-
-	return 0;
-}
-
-/***********************************************************************
-  PEAK FILE STUFF
- ***********************************************************************/
-
-void*
-Source::peak_thread_work (void* arg)
-{
-	PBD::ThreadCreated (pthread_self(), X_("Peak"));
-	struct pollfd pfd[1];
-
-	Glib::Mutex::Lock lm (pending_peak_sources_lock);
-
-	while (true) {
-
-		pfd[0].fd = peak_request_pipe[0];
-		pfd[0].events = POLLIN|POLLERR|POLLHUP;
-
-		pending_peak_sources_lock.unlock();
-
-		if (poll (pfd, 1, -1) < 0) {
-
-			if (errno == EINTR) {
-				pending_peak_sources_lock.lock();
-				continue;
-			}
-			
-			error << string_compose (_("poll on peak request pipe failed (%1)"),
-					  strerror (errno))
-			      << endmsg;
-			break;
-		}
-
-		if (pfd[0].revents & ~POLLIN) {
-			error << _("Error on peak thread request pipe") << endmsg;
-			break;
-		}
-
-		if (pfd[0].revents & POLLIN) {
-
-			char req;
-			
-			/* empty the pipe of all current requests */
-
-			while (1) {
-				size_t nread = ::read (peak_request_pipe[0], &req, sizeof (req));
-
-				if (nread == 1) {
-					switch ((PeakRequest::Type) req) {
-					
-					case PeakRequest::Build:
-						break;
-						
-					case PeakRequest::Quit:
-						pthread_exit_pbd (0);
-						/*NOTREACHED*/
-						break;
-						
-					default:
-						break;
-					}
-
-				} else if (nread == 0) {
-					break;
-				} else if (errno == EAGAIN) {
-					break;
-				} else {
-					fatal << _("Error reading from peak request pipe") << endmsg;
-					/*NOTREACHED*/
-				}
-			}
-		}
-
-		pending_peak_sources_lock.lock();
-
-		while (!pending_peak_sources.empty()) {
-
-			Source* s = pending_peak_sources.front();
-			pending_peak_sources.erase (pending_peak_sources.begin());
-
-			pending_peak_sources_lock.unlock();
-			s->build_peaks();
-			pending_peak_sources_lock.lock();
-		}
-	}
-
-	pthread_exit_pbd (0);
-	/*NOTREACHED*/
-	return 0;
-}
-
-int
-Source::start_peak_thread ()
-{
-	if (!_build_peakfiles) {
-		return 0;
-	}
-
-	if (pipe (peak_request_pipe)) {
-		error << string_compose(_("Cannot create transport request signal pipe (%1)"), strerror (errno)) << endmsg;
-		return -1;
-	}
-
-	if (fcntl (peak_request_pipe[0], F_SETFL, O_NONBLOCK)) {
-		error << string_compose(_("UI: cannot set O_NONBLOCK on peak request pipe (%1)"), strerror (errno)) << endmsg;
-		return -1;
-	}
-
-	if (fcntl (peak_request_pipe[1], F_SETFL, O_NONBLOCK)) {
-		error << string_compose(_("UI: cannot set O_NONBLOCK on peak request pipe (%1)"), strerror (errno)) << endmsg;
-		return -1;
-	}
-
-	if (pthread_create_and_store ("peak file builder", &peak_thread, 0, peak_thread_work, 0)) {
-		error << _("Source: could not create peak thread") << endmsg;
-		return -1;
-	}
-
-	have_peak_thread = true;
 	return 0;
 }
 
 void
-Source::stop_peak_thread ()
-{
-	if (!have_peak_thread) {
-		return;
-	}
-
-	void* status;
-
-	char c = (char) PeakRequest::Quit;
-	::write (peak_request_pipe[1], &c, 1);
-	pthread_join (peak_thread, &status);
-}
-
-void 
-Source::queue_for_peaks (Source& source)
-{
-	if (have_peak_thread) {
-
-		Glib::Mutex::Lock lm (pending_peak_sources_lock);
-
-		source.next_peak_clear_should_notify = true;
-
-		if (find (pending_peak_sources.begin(),
-			  pending_peak_sources.end(),
-			  &source) == pending_peak_sources.end()) {
-			pending_peak_sources.push_back (&source);
-		}
-
-		char c = (char) PeakRequest::Build;
-		::write (peak_request_pipe[1], &c, 1);
-	}
-}
-
-void Source::clear_queue_for_peaks ()
-{
-	/* this is done to cancel a group of running peak builds */
-	if (have_peak_thread) {
-		Glib::Mutex::Lock lm (pending_peak_sources_lock);
-		pending_peak_sources.clear ();
-	}
-}
-
-
-bool
-Source::peaks_ready (sigc::slot<void> the_slot, sigc::connection& conn) const
-{
-	bool ret;
-	Glib::Mutex::Lock lm (_lock);
-
-	/* check to see if the peak data is ready. if not
-	   connect the slot while still holding the lock.
-	*/
-
-	if (!(ret = _peaks_built)) {
-		conn = PeaksReady.connect (the_slot);
-	}
-
-	return ret;
-}
-
-int
-Source::rename_peakfile (string newpath)
-{
-	/* caller must hold _lock */
-
-	string oldpath = peakpath;
-
-	if (access (oldpath.c_str(), F_OK) == 0) {
-		if (rename (oldpath.c_str(), newpath.c_str()) != 0) {
-			error << string_compose (_("cannot rename peakfile for %1 from %2 to %3 (%4)"), _name, oldpath, newpath, strerror (errno)) << endmsg;
-			return -1;
-		}
-	}
-
-	peakpath = newpath;
-
-	return 0;
-}
-
-int
-Source::initialize_peakfile (bool newfile, string audio_path)
-{
-	struct stat statbuf;
-
-	peakpath = peak_path (audio_path);
-
-	if (newfile) {
-
-		if (!_build_peakfiles) {
-			return 0;
-		}
-
-		_peaks_built = false;
-
-	} else {
-
-		if (stat (peakpath.c_str(), &statbuf)) {
-			if (errno != ENOENT) {
-				/* it exists in the peaks dir, but there is some kind of error */
-				
-				error << string_compose(_("Source: cannot stat peakfile \"%1\""), peakpath) << endmsg;
-				return -1;
-			}
-
-		} else {
-			
-			/* we found it in the peaks dir */
-		}
-		
-		if (statbuf.st_size == 0) {
-			_peaks_built = false;
-		} else {
-			// Check if the audio file has changed since the peakfile was built.
-			struct stat stat_file;
-			int err = stat (audio_path.c_str(), &stat_file);
-			
-			if (!err && stat_file.st_mtime > statbuf.st_mtime){
-				_peaks_built = false;
-			} else {
-				_peaks_built = true;
-			}
-		}
-	}
-
-	if (!newfile && !_peaks_built && _build_missing_peakfiles && _build_peakfiles) {
-		build_peaks_from_scratch ();
-	} 
-
-	return 0;
-}
-
-int 
-Source::read_peaks (PeakData *peaks, jack_nframes_t npeaks, jack_nframes_t start, jack_nframes_t cnt, double samples_per_visual_peak) const
-{
-	Glib::Mutex::Lock lm (_lock);
-	double scale;
-	double expected_peaks;
-	PeakData::PeakDatum xmax;
-	PeakData::PeakDatum xmin;
-	int32_t to_read;
-	uint32_t nread;
-	jack_nframes_t zero_fill = 0;
-	int ret = -1;
-	PeakData* staging = 0;
-	Sample* raw_staging = 0;
-	char * workbuf = 0;
-	int peakfile = -1;
-
-	expected_peaks = (cnt / (double) frames_per_peak);
-	scale = npeaks/expected_peaks;
-
-#if 0
-	cerr << "======>RP: npeaks = " << npeaks 
-	     << " start = " << start 
-	     << " cnt = " << cnt 
-	     << " len = " << _length 
-	     << "   samples_per_visual_peak =" << samples_per_visual_peak 
-	     << " expected was " << expected_peaks << " ... scale = " << scale
-	     << " PD ptr = " << peaks
-	     <<endl;
-	
-#endif
-
-	/* fix for near-end-of-file conditions */
-
-	if (cnt > _length - start) {
-		// cerr << "too close to end @ " << _length << " given " << start << " + " << cnt << endl;
-		cnt = _length - start;
-		jack_nframes_t old = npeaks;
-		npeaks = min ((jack_nframes_t) floor (cnt / samples_per_visual_peak), npeaks);
-		zero_fill = old - npeaks;
-	}
-
-	// cerr << "actual npeaks = " << npeaks << " zf = " << zero_fill << endl;
-	
-	if (npeaks == cnt) {
-
-		// cerr << "RAW DATA\n";
-		
-		/* no scaling at all, just get the sample data and duplicate it for
-		   both max and min peak values.
-		*/
-
-		Sample* raw_staging = new Sample[cnt];
-		workbuf = new char[cnt*4];
-		
-		if (read_unlocked (raw_staging, start, cnt, workbuf) != cnt) {
-			error << _("cannot read sample data for unscaled peak computation") << endmsg;
-			return -1;
-		}
-
-		for (jack_nframes_t i = 0; i < npeaks; ++i) {
-			peaks[i].max = raw_staging[i];
-			peaks[i].min = raw_staging[i];
-		}
-
-		delete [] raw_staging;
-		delete [] workbuf;
-		return 0;
-	}
-
-	if (scale == 1.0) {
-
-		off_t first_peak_byte = (start / frames_per_peak) * sizeof (PeakData);
-
-		/* open, read, close */
-
-		if ((peakfile = ::open (peakpath.c_str(), O_RDWR|O_CREAT, 0664)) < 0) {
-			error << string_compose(_("Source: cannot open peakpath \"%1\" (%2)"), peakpath, strerror (errno)) << endmsg;
-			return -1;
-		}
-
-		// cerr << "DIRECT PEAKS\n";
-		
-		nread = ::pread (peakfile, peaks, sizeof (PeakData)* npeaks, first_peak_byte);
-		close (peakfile);
-
-		if (nread != sizeof (PeakData) * npeaks) {
-			cerr << "Source["
-			     << _name
-			     << "]: cannot read peaks from peakfile! (read only " 
-			     << nread
-			     << " not " 
-			     << npeaks
-			      << "at sample " 
-			     << start
-			     << " = byte "
-			     << first_peak_byte
-			     << ')'
-			     << endl;
-			return -1;
-		}
-
-		if (zero_fill) {
-			memset (&peaks[npeaks], 0, sizeof (PeakData) * zero_fill);
-		}
-
-		return 0;
-	}
-
-
-	jack_nframes_t tnp;
-
-	if (scale < 1.0) {
-
-		// cerr << "DOWNSAMPLE\n";
-
-		/* the caller wants:
-
-		    - more frames-per-peak (lower resolution) than the peakfile, or to put it another way,
-                    - less peaks than the peakfile holds for the same range
-
-		    So, read a block into a staging area, and then downsample from there.
-
-		    to avoid confusion, I'll refer to the requested peaks as visual_peaks and the peakfile peaks as stored_peaks  
-		*/
-
-		const uint32_t chunksize = (uint32_t) min (expected_peaks, 4096.0);
-		
-		staging = new PeakData[chunksize];
-		
-		/* compute the rounded up frame position  */
-	
-		jack_nframes_t current_frame = start;
-		jack_nframes_t current_stored_peak = (jack_nframes_t) ceil (current_frame / (double) frames_per_peak);
-		uint32_t       next_visual_peak  = (uint32_t) ceil (current_frame / samples_per_visual_peak);
-		double         next_visual_peak_frame = next_visual_peak * samples_per_visual_peak;
-		uint32_t       stored_peak_before_next_visual_peak = (jack_nframes_t) next_visual_peak_frame / frames_per_peak;
-		uint32_t       nvisual_peaks = 0;
-		uint32_t       stored_peaks_read = 0;
-		uint32_t       i = 0;
-
-		/* handle the case where the initial visual peak is on a pixel boundary */
-
-		current_stored_peak = min (current_stored_peak, stored_peak_before_next_visual_peak);
-
-		/* open ... close during out: handling */
-
-		if ((peakfile = ::open (peakpath.c_str(), O_RDWR|O_CREAT, 0664)) < 0) {
-			error << string_compose(_("Source: cannot open peakpath \"%1\" (%2)"), peakpath, strerror (errno)) << endmsg;
-			return 0;
-		}
-
-		while (nvisual_peaks < npeaks) {
-
-			if (i == stored_peaks_read) {
-
-				uint32_t       start_byte = current_stored_peak * sizeof(PeakData);
-				tnp = min ((_length/frames_per_peak - current_stored_peak), (jack_nframes_t) expected_peaks);
-				to_read = min (chunksize, tnp);
-				
-				off_t fend = lseek (peakfile, 0, SEEK_END);
-				
-				if ((nread = ::pread (peakfile, staging, sizeof (PeakData) * to_read, start_byte))
-				    != sizeof (PeakData) * to_read) {
-					cerr << "Source["
-					     << _name
-					     << "]: cannot read peak data from peakfile ("
-					     << (nread / sizeof(PeakData))
-					     << " peaks instead of "
-					     << to_read
-					     << ") ("
-					     << strerror (errno)
-					     << ')'
-					     << " at start_byte = " << start_byte 
-					     << " _length = " << _length << " versus len = " << fend
-					     << " expected maxpeaks = " << (_length - current_frame)/frames_per_peak
-					     << " npeaks was " << npeaks
-					     << endl;
-					goto out;
-				}
-
-				i = 0;
-				stored_peaks_read = nread / sizeof(PeakData);
-			}
-
-			xmax = -1.0;
-			xmin = 1.0;
-
-			while ((i < stored_peaks_read) && (current_stored_peak <= stored_peak_before_next_visual_peak)) {
-
-				xmax = max (xmax, staging[i].max);
-				xmin = min (xmin, staging[i].min);
-				++i;
-				++current_stored_peak;
-				--expected_peaks;
-			}
-
-			peaks[nvisual_peaks].max = xmax;
-			peaks[nvisual_peaks].min = xmin;
-			++nvisual_peaks;
-			++next_visual_peak;
-
-			//next_visual_peak_frame = min ((next_visual_peak * samples_per_visual_peak), (next_visual_peak_frame+samples_per_visual_peak) );
-			next_visual_peak_frame =  min ((double) start+cnt, (next_visual_peak_frame+samples_per_visual_peak) );
-			stored_peak_before_next_visual_peak = (uint32_t) next_visual_peak_frame / frames_per_peak; 
-		}
-
-		if (zero_fill) {
- 			memset (&peaks[npeaks], 0, sizeof (PeakData) * zero_fill);
- 		}
-		
-		ret = 0;
-
-	} else {
-		
-		// cerr << "UPSAMPLE\n";
-
-		/* the caller wants 
-
-		     - less frames-per-peak (more resolution)
-		     - more peaks than stored in the Peakfile
-
-		   So, fetch data from the raw source, and generate peak
-		   data on the fly.
-		*/
-
-		jack_nframes_t frames_read = 0;
-		jack_nframes_t current_frame = start;
-		jack_nframes_t i = 0;
-		jack_nframes_t nvisual_peaks = 0;
-		jack_nframes_t chunksize = (jack_nframes_t) min (cnt, (jack_nframes_t) 4096);
-		raw_staging = new Sample[chunksize];
-		workbuf = new char[chunksize *4];
-		
-		jack_nframes_t frame_pos = start;
-		double pixel_pos = floor (frame_pos / samples_per_visual_peak);
-		double next_pixel_pos = ceil (frame_pos / samples_per_visual_peak);
-		double pixels_per_frame = 1.0 / samples_per_visual_peak;
-
-		xmin = 1.0;
-		xmax = -1.0;
-
-		while (nvisual_peaks < npeaks) {
-
-			if (i == frames_read) {
-				
-				to_read = min (chunksize, (_length - current_frame));
-				
-				if ((frames_read = read_unlocked (raw_staging, current_frame, to_read, workbuf)) < 0) {
-					error << string_compose(_("Source[%1]: peak read - cannot read %2 samples at offset %3")
-							 , _name, to_read, current_frame) 
-					      << endmsg;
-					goto out;
-				}
-
-				i = 0;
-			}
-			
-			xmax = max (xmax, raw_staging[i]);
-			xmin = min (xmin, raw_staging[i]);
-			++i;
-			++current_frame;
-			pixel_pos += pixels_per_frame;
-
-			if (pixel_pos >= next_pixel_pos) {
-
-				peaks[nvisual_peaks].max = xmax;
-				peaks[nvisual_peaks].min = xmin;
-				++nvisual_peaks;
-				xmin = 1.0;
-				xmax = -1.0;
-
-				next_pixel_pos = ceil (pixel_pos + 0.5);
-			}
-		}
-		
-		if (zero_fill) {
-			memset (&peaks[npeaks], 0, sizeof (PeakData) * zero_fill);
-		}
-
-		ret = 0;
-	}
-
-  out:
-	if (peakfile >= 0) {
-		close (peakfile);
-	}
-
-	if (staging) {
-		delete [] staging;
-	} 
-
-	if (raw_staging) {
-		delete [] raw_staging;
-	}
-
-	if (workbuf) {
-		delete [] workbuf;
-	}
-	
-	return ret;
-}
-
-#undef DEBUG_PEAK_BUILD
-
-int
-Source::build_peaks ()
-{
-	vector<PeakBuildRecord*> built;
-	int status = -1;
-	bool pr_signal = false;
-	list<PeakBuildRecord*> copy;
-
-	{
-		Glib::Mutex::Lock lm (_lock);
-		copy = pending_peak_builds;
-		pending_peak_builds.clear ();
-	}
-		
-#ifdef DEBUG_PEAK_BUILD
-	cerr << "build peaks with " << copy.size() << " requests pending\n";
-#endif		
-
-	for (list<PeakBuildRecord *>::iterator i = copy.begin(); i != copy.end(); ++i) {
-		
-		if ((status = do_build_peak ((*i)->frame, (*i)->cnt)) != 0) { 
-			unlink (peakpath.c_str());
-			break;
-		}
-		built.push_back (new PeakBuildRecord (*(*i)));
-		delete *i;
-	}
-
-	{ 
-		Glib::Mutex::Lock lm (_lock);
-
-		if (status == 0) {
-			_peaks_built = true;
-			
-			if (next_peak_clear_should_notify) {
-				next_peak_clear_should_notify = false;
-				pr_signal = true;
-			}
-		}
-	}
-
-	if (status == 0) {
-		for (vector<PeakBuildRecord *>::iterator i = built.begin(); i != built.end(); ++i) {
-			PeakRangeReady ((*i)->frame, (*i)->cnt); /* EMIT SIGNAL */
-			delete *i;
-		}
-
-		if (pr_signal) {
-			PeaksReady (); /* EMIT SIGNAL */
-		}
-	}
-
-	return status;
-}
-
-int
-Source::do_build_peak (jack_nframes_t first_frame, jack_nframes_t cnt)
-{
-	jack_nframes_t current_frame;
-	Sample buf[frames_per_peak];
-	Sample xmin, xmax;
-	uint32_t  peaki;
-	PeakData* peakbuf;
-	char * workbuf = 0;
-	jack_nframes_t frames_read;
-	jack_nframes_t frames_to_read;
-	off_t first_peak_byte;
-	int peakfile = -1;
-	int ret = -1;
-
-#ifdef DEBUG_PEAK_BUILD
-	cerr << pthread_self() << ": " << _name << ": building peaks for " << first_frame << " to " << first_frame + cnt - 1 << endl;
-#endif
-
-	first_peak_byte = (first_frame / frames_per_peak) * sizeof (PeakData);
-
-#ifdef DEBUG_PEAK_BUILD
-	cerr << "seeking to " << first_peak_byte << " before writing new peak data\n";
-#endif
-
-	current_frame = first_frame;
-	peakbuf = new PeakData[(cnt/frames_per_peak)+1];
-	peaki = 0;
-
-	workbuf = new char[max(frames_per_peak, cnt) * 4];
-	
-	if ((peakfile = ::open (peakpath.c_str(), O_RDWR|O_CREAT, 0664)) < 0) {
-		error << string_compose(_("Source: cannot open peakpath \"%1\" (%2)"), peakpath, strerror (errno)) << endmsg;
-		return -1;
-	}
-	
-	while (cnt) {
-
-		frames_to_read = min (frames_per_peak, cnt);
-
-		if ((frames_read = read_unlocked (buf, current_frame, frames_to_read, workbuf)) != frames_to_read) {
-			error << string_compose(_("%1: could not write read raw data for peak computation (%2)"), _name, strerror (errno)) << endmsg;
-			goto out;
-		}
-
-		xmin = buf[0];
-		xmax = buf[0];
-
-		for (jack_nframes_t n = 1; n < frames_read; ++n) {
-			xmax = max (xmax, buf[n]);
-			xmin = min (xmin, buf[n]);
-
-//			if (current_frame < frames_read) {
-//				cerr << "sample = " << buf[n] << " max = " << xmax << " min = " << xmin << " max of 2 = " << max (xmax, buf[n]) << endl;
-//			}
-		}
-
-		peakbuf[peaki].max = xmax;
-		peakbuf[peaki].min = xmin;
-		peaki++;
-
-		current_frame += frames_read;
-		cnt -= frames_read;
-	}
-
-	if (::pwrite (peakfile, peakbuf, sizeof (PeakData) * peaki, first_peak_byte) != (ssize_t) (sizeof (PeakData) * peaki)) {
-		error << string_compose(_("%1: could not write peak file data (%2)"), _name, strerror (errno)) << endmsg;
-		goto out;
-	}
-
-	ret = 0;
-
-  out:
-	delete [] peakbuf;
-	if (peakfile >= 0) {
-		close (peakfile);
-	}
-	if (workbuf)
-		delete [] workbuf;
-	return ret;
-}
-
-void
-Source::build_peaks_from_scratch ()
-{
-	Glib::Mutex::Lock lp (_lock); 
-
-	next_peak_clear_should_notify = true;
-	pending_peak_builds.push_back (new PeakBuildRecord (0, _length));
-	queue_for_peaks (*this);
-}
-
-bool
-Source::file_changed (string path)
-{
-	struct stat stat_file;
-	struct stat stat_peak;
-
-	int e1 = stat (path.c_str(), &stat_file);
-	int e2 = stat (peak_path(path).c_str(), &stat_peak);
-	
-	if (!e1 && !e2 && stat_file.st_mtime > stat_peak.st_mtime){
-		return true;
-	} else {
-		return false;
-	}
-}
-
-void
 Source::use ()
 {
 	_use_cnt++;
@@ -864,30 +118,3 @@ Source::release ()
 	if (_use_cnt) --_use_cnt;
 }
 
-jack_nframes_t
-Source::available_peaks (double zoom_factor) const
-{
-	int peakfile;
-	off_t end;
-
-	if (zoom_factor < frames_per_peak) {
-		return length(); // peak data will come from the audio file
-	} 
-	
-	/* peak data comes from peakfile */
-
-	if ((peakfile = ::open (peakpath.c_str(), O_RDONLY)) < 0) {
-		error << string_compose(_("Source: cannot open peakpath \"%1\" (%2)"), peakpath, strerror (errno)) << endmsg;
-		return 0;
-	}
-
-	{ 
-		Glib::Mutex::Lock lm (_lock);
-		end = lseek (peakfile, 0, SEEK_END);
-	}
-
-	close (peakfile);
-
-	return (end/sizeof(PeakData)) * frames_per_peak;
-}
-