Very basic audio processing framework.

1 files changed, 72 insertions, 0 deletions

diff --git a/src/lib/mid_side_decoder.cc b/src/lib/mid_side_decoder.cc
new file mode 100644
index 000000000..a518a4389
--- /dev/null
+++ b/src/lib/mid_side_decoder.cc
@@ -0,0 +1,72 @@
+/*
+    Copyright (C) 2014 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 "mid_side_decoder.h"
+#include "audio_buffers.h"
+
+#include "i18n.h"
+
+using std::string;
+using boost::shared_ptr;
+
+string
+MidSideDecoder::name () const
+{
+	return _("Mid-side decoder");
+}
+
+string
+MidSideDecoder::id () const
+{
+	return N_("mid-side-decoder");
+}
+
+ChannelCount
+MidSideDecoder::in_channels () const
+{
+	return ChannelCount (2);
+}
+
+int
+MidSideDecoder::out_channels (int) const
+{
+	return 3;
+}
+
+shared_ptr<AudioProcessor>
+MidSideDecoder::clone () const
+{
+	return shared_ptr<AudioProcessor> (new MidSideDecoder ());
+}
+
+shared_ptr<AudioBuffers>
+MidSideDecoder::run (shared_ptr<const AudioBuffers> in)
+{
+	shared_ptr<AudioBuffers> out (new AudioBuffers (3, in->frames ()));
+	for (int i = 0; i < in->frames(); ++i) {
+		float const left = in->data()[0][i];
+		float const right = in->data()[1][i];
+		float const mid = (left + right) / 2;
+		out->data()[0][i] = left - mid;
+		out->data()[1][i] = right - mid;
+		out->data()[2][i] = mid;
+	}
+
+	return out;
+}