rollback to 3428, before the mysterious removal of libs/* at 3431/3432

git-svn-id: svn://localhost/ardour2/branches/3.0@3435 d708f5d6-7413-0410-9779-e7cbd77b26cf

1 files changed, 165 insertions, 0 deletions

diff --git a/libs/ardour/meter.cc b/libs/ardour/meter.cc
new file mode 100644
index 0000000000..e75c1d89ca
--- /dev/null
+++ b/libs/ardour/meter.cc
@@ -0,0 +1,165 @@
+/*
+    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 <ardour/meter.h>
+#include <algorithm>
+#include <cmath>
+#include <ardour/buffer_set.h>
+#include <ardour/peak.h>
+#include <ardour/dB.h>
+#include <ardour/session.h>
+
+namespace ARDOUR {
+
+
+/** Get peaks from @a bufs
+ * Input acceptance is lenient - the first n buffers from @a bufs will
+ * be metered, where n was set by the last call to setup(), excess meters will
+ * be set to 0.
+ */
+void
+PeakMeter::run_in_place (BufferSet& bufs, nframes_t start_frame, nframes_t end_frame, nframes_t nframes, nframes_t offset)
+{
+	size_t meterable = std::min((size_t)bufs.count().n_total(), _peak_power.size());
+
+	size_t n = 0;
+
+	// Meter what we have (midi)
+	for ( ; n < meterable && n < bufs.count().n_midi(); ++n) {
+	
+		float val = 0;
+		
+		// GUI needs a better MIDI meter, not much information can be
+		// expressed through peaks alone
+		for (MidiBuffer::iterator i = bufs.get_midi(n).begin(); i != bufs.get_midi(n).end(); ++i) {
+			const MIDI::Event& ev = *i;
+			if (ev.is_note_on()) {
+				const float this_vel = log(ev.buffer()[2] / 127.0 * (M_E*M_E-M_E) + M_E) - 1.0;
+				//printf("V %d -> %f\n", (int)((Byte)ev.buffer[2]), this_vel);
+				if (this_vel > val)
+					val = this_vel;
+			} else {
+				val += 1.0 / bufs.get_midi(n).capacity();
+				if (val > 1.0)
+					val = 1.0;
+			}
+		}
+			
+		_peak_power[n] = val;
+
+	}
+	
+	// Meter what we have (audio)
+	for ( ; n < meterable && n < bufs.count().n_audio(); ++n) {
+		_peak_power[n] = compute_peak (bufs.get_audio(n).data(nframes, offset), nframes, _peak_power[n]); 
+	}
+
+	// Zero any excess peaks
+	for (size_t n = meterable; n < _peak_power.size(); ++n) {
+		_peak_power[n] = 0;
+	}
+}
+
+void
+PeakMeter::reset ()
+{
+	for (size_t i = 0; i < _peak_power.size(); ++i) {
+		_peak_power[i] = 0;
+	}
+}
+
+void
+PeakMeter::reset_max ()
+{
+	for (size_t i = 0; i < _max_peak_power.size(); ++i) {
+		_max_peak_power[i] = -INFINITY;
+	}
+}
+
+bool
+PeakMeter::configure_io (ChanCount in, ChanCount out)
+{
+	/* we're transparent no matter what.  fight the power. */
+	if (out != in)
+		return false;
+
+	uint32_t limit = in.n_total();
+
+	while (_peak_power.size() > limit) {
+		_peak_power.pop_back();
+		_visible_peak_power.pop_back();
+		_max_peak_power.pop_back();
+	}
+
+	while (_peak_power.size() < limit) {
+		_peak_power.push_back(0);
+		_visible_peak_power.push_back(minus_infinity());
+		_max_peak_power.push_back(minus_infinity());
+	}
+
+	assert(_peak_power.size() == limit);
+	assert(_visible_peak_power.size() == limit);
+	assert(_max_peak_power.size() == limit);
+
+	Processor::configure_io(in, out);
+
+	return true;
+}
+
+/** To be driven by the Meter signal from IO.
+ * Caller MUST hold io_lock!
+ */
+void
+PeakMeter::meter ()
+{
+	assert(_visible_peak_power.size() == _peak_power.size());
+
+	const size_t limit = _peak_power.size();
+
+	for (size_t n = 0; n < limit; ++n) {
+
+		/* XXX we should use atomic exchange here */
+
+		/* grab peak since last read */
+
+ 		float new_peak = _peak_power[n];
+		_peak_power[n] = 0;
+		
+		/* compute new visible value using falloff */
+
+		if (new_peak > 0.0) {
+			new_peak = coefficient_to_dB (new_peak);
+		} else {
+			new_peak = minus_infinity();
+		}
+		
+		/* update max peak */
+		
+		_max_peak_power[n] = std::max (new_peak, _max_peak_power[n]);
+		
+		if (Config->get_meter_falloff() == 0.0f || new_peak > _visible_peak_power[n]) {
+			_visible_peak_power[n] = new_peak;
+		} else {
+			// do falloff
+			new_peak = _visible_peak_power[n] - (Config->get_meter_falloff() * 0.01f);
+			_visible_peak_power[n] = std::max (new_peak, -INFINITY);
+		}
+	}
+}
+
+} // namespace ARDOUR