Add UpmixerB.

1 files changed, 139 insertions, 0 deletions

diff --git a/src/lib/upmixer_b.cc b/src/lib/upmixer_b.cc
new file mode 100644
index 000000000..9340582c3
--- /dev/null
+++ b/src/lib/upmixer_b.cc
@@ -0,0 +1,139 @@
+/*
+    Copyright (C) 2015 Carl Hetherington <cth@carlh.net>
+
+    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 "upmixer_b.h"
+#include "audio_buffers.h"
+#include "audio_mapping.h"
+
+#include "i18n.h"
+
+using std::string;
+using std::min;
+using std::vector;
+using boost::shared_ptr;
+
+UpmixerB::UpmixerB (int sampling_rate)
+	: _lfe (0.02, 20.0 / sampling_rate, 150.0 / sampling_rate)
+	, _delay (0.02 * sampling_rate)
+{
+
+}
+
+string
+UpmixerB::name () const
+{
+	return _("Stereo to 5.1 up-mixer B");
+}
+
+
+string
+UpmixerB::id () const
+{
+	return N_("stereo-5.1-upmix-b");
+}
+
+int
+UpmixerB::out_channels () const
+{
+	return 6;
+}
+
+shared_ptr<AudioProcessor>
+UpmixerB::clone (int sampling_rate) const
+{
+	return shared_ptr<AudioProcessor> (new UpmixerB (sampling_rate));
+}
+
+shared_ptr<AudioBuffers>
+UpmixerB::run (shared_ptr<const AudioBuffers> in, int channels)
+{
+	shared_ptr<AudioBuffers> out (new AudioBuffers (channels, in->frames()));
+
+	/* L + R minus 6dB (in terms of amplitude) */
+	shared_ptr<AudioBuffers> in_LR = in->channel(0);
+	in_LR->accumulate_frames (in->channel(1).get(), 0, 0, in->frames());
+	in_LR->apply_gain (-6);
+
+	if (channels > 0) {
+		/* L = Lt */
+		out->copy_channel_from (in.get(), 0, 0);
+	}
+
+	if (channels > 1) {
+		/* R = Rt */
+		out->copy_channel_from (in.get(), 1, 1);
+	}
+
+	if (channels > 2) {
+		/* C = L + R minus 3dB */
+		out->copy_channel_from (in_LR.get(), 0, 2);
+	}
+
+	if (channels > 3) {
+		/* Lfe is filtered C */
+		out->copy_channel_from (_lfe.run(in_LR).get(), 0, 3);
+	}
+
+	shared_ptr<AudioBuffers> S;
+	if (channels > 4) {
+		/* Ls is L - R with some delay */
+		shared_ptr<AudioBuffers> sub (new AudioBuffers (1, in->frames()));
+		sub->copy_channel_from (in.get(), 0, 0);
+		float* p = sub->data (0);
+		float const * q = in->data (1);
+		for (int i = 0; i < in->frames(); ++i) {
+			*p++ -= *q++;
+		}
+		S = _delay.run (sub);
+		out->copy_channel_from (S.get(), 0, 4);
+	}
+
+	if (channels > 5) {
+		/* Rs = Ls */
+		out->copy_channel_from (S.get(), 0, 5);
+	}
+
+	return out;
+}
+
+void
+UpmixerB::flush ()
+{
+	_lfe.flush ();
+	_delay.flush ();
+}
+
+void
+UpmixerB::make_audio_mapping_default (AudioMapping& mapping) const
+{
+	/* Just map the first two input channels to our L/R */
+	mapping.make_zero ();
+	for (int i = 0; i < min (2, mapping.input_channels()); ++i) {
+		mapping.set (i, i, 1);
+	}
+}
+
+vector<string>
+UpmixerB::input_names () const
+{
+	vector<string> n;
+	n.push_back (_("Upmix L"));
+	n.push_back (_("Upmix R"));
+	return n;
+}