Add simple sample-access API to SoundFrame.

4 files changed, 74 insertions, 2 deletions

diff --git a/src/sound_asset_writer.cc b/src/sound_asset_writer.cc
index 74bf866e..e628b26e 100644
--- a/src/sound_asset_writer.cc
+++ b/src/sound_asset_writer.cc
@@ -38,9 +38,11 @@
 #include "compose.hpp"
 #include "encryption_context.h"
 #include <asdcp/AS_DCP.h>
+#include <iostream>
 
 using std::min;
 using std::max;
+using std::cout;
 using namespace dcp;
 
 struct SoundAssetWriter::ASDCPState
diff --git a/src/sound_frame.cc b/src/sound_frame.cc
new file mode 100644
index 00000000..915099a8
--- /dev/null
+++ b/src/sound_frame.cc
@@ -0,0 +1,60 @@
+/*
+    Copyright (C) 2012-2017 Carl Hetherington <cth@carlh.net>
+
+    This file is part of libdcp.
+
+    libdcp 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.
+
+    libdcp 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 libdcp.  If not, see <http://www.gnu.org/licenses/>.
+
+    In addition, as a special exception, the copyright holders give
+    permission to link the code of portions of this program with the
+    OpenSSL library under certain conditions as described in each
+    individual source file, and distribute linked combinations
+    including the two.
+
+    You must obey the GNU General Public License in all respects
+    for all of the code used other than OpenSSL.  If you modify
+    file(s) with this exception, you may extend this exception to your
+    version of the file(s), but you are not obligated to do so.  If you
+    do not wish to do so, delete this exception statement from your
+    version.  If you delete this exception statement from all source
+    files in the program, then also delete it here.
+*/
+
+#include "sound_frame.h"
+#include <asdcp/AS_DCP.h>
+#include <iostream>
+
+using std::cout;
+using namespace dcp;
+
+SoundFrame::SoundFrame (ASDCP::PCM::MXFReader* reader, int n, boost::shared_ptr<const DecryptionContext> c)
+	: Frame (reader, n, c)
+{
+	ASDCP::PCM::AudioDescriptor desc;
+	reader->FillAudioDescriptor (desc);
+	_channels = desc.ChannelCount;
+}
+
+int32_t
+SoundFrame::get (int channel, int frame) const
+{
+	uint8_t const * d = data() + (frame * _channels * 3) + (channel * 3);
+	return d[0] | (d[1] << 8) | (d[2] << 16);
+}
+
+int
+SoundFrame::samples () const
+{
+	return size() / (_channels * 3);
+}
diff --git a/src/sound_frame.h b/src/sound_frame.h
index 2b78c8e1..e58e4bf3 100644
--- a/src/sound_frame.h
+++ b/src/sound_frame.h
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2012-2014 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2012-2017 Carl Hetherington <cth@carlh.net>
 
     This file is part of libdcp.
 
@@ -43,7 +43,16 @@
 
 namespace dcp {
 
-typedef Frame<ASDCP::PCM::MXFReader, ASDCP::PCM::FrameBuffer> SoundFrame;
+class SoundFrame : public Frame<ASDCP::PCM::MXFReader, ASDCP::PCM::FrameBuffer>
+{
+public:
+	SoundFrame (ASDCP::PCM::MXFReader* reader, int n, boost::shared_ptr<const DecryptionContext> c);
+	int samples () const;
+	int32_t get (int channel, int sample) const;
+
+private:
+	int _channels;
+};
 
 }
 
diff --git a/src/wscript b/src/wscript
index 3fd10639..dd8ee4e5 100644
--- a/src/wscript
+++ b/src/wscript
@@ -90,6 +90,7 @@ def build(bld):
              smpte_subtitle_asset.cc
              sound_asset.cc
              sound_asset_writer.cc
+             sound_frame.cc
              stereo_picture_asset.cc
              stereo_picture_asset_writer.cc
              stereo_picture_frame.cc