Add files missing from previous commit.

git-svn-id: svn://localhost/ardour2/branches/3.0@5011 d708f5d6-7413-0410-9779-e7cbd77b26cf

1 files changed, 125 insertions, 0 deletions

diff --git a/libs/ardour/strip_silence.cc b/libs/ardour/strip_silence.cc
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+/*
+    Copyright (C) 2009 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 "ardour/strip_silence.h"
+#include "ardour/audioregion.h"
+#include "ardour/region_factory.h"
+#include "ardour/session.h"
+#include "ardour/dB.h"
+
+using namespace ARDOUR;
+
+/** Construct a StripSilence filter.
+ *  @param s Session.
+ *  @param threshold Threshold below which audio is considered silence, in dBFS.
+ *  @param minimum_length Minimum length of silence period to recognise, in samples.
+ *  @param fade_length Length of fade in/out to apply to trimmed regions, in samples.
+ */
+ 
+StripSilence::StripSilence (Session & s, double threshold, nframes_t minimum_length, nframes_t fade_length)
+	: Filter (s), _threshold (threshold), _minimum_length (minimum_length), _fade_length (fade_length)
+{
+
+}
+
+int
+StripSilence::run (boost::shared_ptr<Region> r)
+{
+	results.clear ();
+	
+	/* we only operate on AudioRegions, for now, though this could be adapted to MIDI
+	   as well I guess */
+	boost::shared_ptr<AudioRegion> region = boost::dynamic_pointer_cast<AudioRegion> (r);
+	if (!region) {
+		results.push_back (r);
+		return -1;
+	}
+
+	/* find periods of silence in the region */
+	std::list<std::pair<nframes_t, nframes_t> > const silence =
+		region->find_silence (dB_to_coefficient (_threshold), _minimum_length);
+
+	if (silence.size () == 1 && silence.front().first == 0 && silence.front().second == region->length() - 1) {
+		/* the region is all silence, so just return with nothing */
+		return 0;
+	}
+
+	if (silence.empty()) {
+		/* no silence in this region */
+		results.push_back (region);
+		return 0;
+	}
+
+	std::list<std::pair<nframes_t, nframes_t > >::const_iterator s = silence.begin ();
+	nframes_t const pos = region->position ();
+	nframes_t const end = region->start () + region->length() - 1;
+	nframes_t const start = region->start ();
+
+	region = boost::dynamic_pointer_cast<AudioRegion> (RegionFactory::create (region));
+	region->set_name (session.new_region_name (region->name ()));
+	boost::shared_ptr<AudioRegion> last_region = region;
+	results.push_back (region);
+	
+	if (s->first == 0) {
+		/* the region starts with some silence */
+
+		/* we must set length to an intermediate value here, otherwise the call
+		** to set_start will fail */
+		region->set_length (region->length() - s->second + _fade_length, 0);
+		region->set_start (start + s->second - _fade_length, 0);
+		region->set_position (pos + s->second - _fade_length, 0); 
+		region->set_fade_in_active (true);
+		region->set_fade_in (AudioRegion::Linear, _fade_length);
+		s++;
+	}
+
+	while (s != silence.end()) {
+
+		/* trim the end of this region */
+		region->trim_end (pos + s->first + _fade_length, 0);
+		region->set_fade_out_active (true);
+		region->set_fade_out (AudioRegion::Linear, _fade_length);
+
+		/* make a new region and trim its start */
+		region = boost::dynamic_pointer_cast<AudioRegion> (RegionFactory::create (region));
+		region->set_name (session.new_region_name (region->name ()));
+		last_region = region;
+		assert (region);
+		results.push_back (region);
+
+		/* set length here for the same reasons as above */
+		region->set_length (region->length() - s->second + _fade_length, 0);
+		region->set_start (start + s->second - _fade_length, 0);
+		region->set_position (pos + s->second - _fade_length, 0);
+		region->set_fade_in_active (true);
+		region->set_fade_in (AudioRegion::Linear, _fade_length);
+
+		s++;
+	}
+
+	if (silence.back().second == end) {
+		/* the last region we created is zero-sized, so just remove it */
+		results.pop_back ();
+	} else {
+		/* finish off the last region */
+		last_region->trim_end (end, 0);
+	}
+
+	return 0;
+}