Add channel assignment support for SMPTE DCPs.

[libdcp.git] / src / sound_asset_writer.cc

diff --git a/src/sound_asset_writer.cc b/src/sound_asset_writer.cc
index 46321a857f9648dd30e285aa3f5fae86664010c6..f7513d9171a4dee55b1f62cb419adfbd4ca8313a 100644 (file)
--- a/src/sound_asset_writer.cc
+++ b/src/sound_asset_writer.cc
@@ -16,6 +16,19 @@
     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_asset_writer.h"
@@ -23,7 +36,8 @@
 #include "exceptions.h"
 #include "dcp_assert.h"
 #include "compose.hpp"
-#include "AS_DCP.h"
+#include "encryption_context.h"
+#include <asdcp/AS_DCP.h>
 
 using std::min;
 using std::max;
@@ -37,7 +51,7 @@ struct SoundAssetWriter::ASDCPState
        ASDCP::PCM::AudioDescriptor audio_desc;
 };
 
-SoundAssetWriter::SoundAssetWriter (SoundAsset* asset, boost::filesystem::path file, Standard standard)
+SoundAssetWriter::SoundAssetWriter (SoundAsset* asset, boost::filesystem::path file, Standard standard, ChannelAssignment assign)
        : AssetWriter (asset, file, standard)
        , _state (new SoundAssetWriter::ASDCPState)
        , _sound_asset (asset)
@@ -52,7 +66,27 @@ SoundAssetWriter::SoundAssetWriter (SoundAsset* asset, boost::filesystem::path f
        _state->audio_desc.BlockAlign = 3 * _sound_asset->channels();
        _state->audio_desc.AvgBps = _sound_asset->sampling_rate() * _state->audio_desc.BlockAlign;
        _state->audio_desc.LinkedTrackID = 0;
-       _state->audio_desc.ChannelFormat = ASDCP::PCM::CF_NONE;
+       if (standard == INTEROP) {
+               _state->audio_desc.ChannelFormat = ASDCP::PCM::CF_NONE;
+       } else {
+               switch (assign) {
+               case CHANNEL_ASSIGNMENT_51:
+                       _state->audio_desc.ChannelFormat = ASDCP::PCM::CF_CFG_1;
+                       break;
+               case CHANNEL_ASSIGNMENT_61:
+                       _state->audio_desc.ChannelFormat = ASDCP::PCM::CF_CFG_2;
+                       break;
+               case CHANNEL_ASSIGNMENT_71:
+                       _state->audio_desc.ChannelFormat = ASDCP::PCM::CF_CFG_3;
+                       break;
+               case CHANNEL_ASSIGNMENT_WTF:
+                       _state->audio_desc.ChannelFormat = ASDCP::PCM::CF_CFG_4;
+                       break;
+               case CHANNEL_ASSIGNMENT_71_DS:
+                       _state->audio_desc.ChannelFormat = ASDCP::PCM::CF_CFG_5;
+                       break;
+               }
+       }
 
        _state->frame_buffer.Capacity (ASDCP::PCM::CalcFrameBufferSize (_state->audio_desc));
        _state->frame_buffer.Size (ASDCP::PCM::CalcFrameBufferSize (_state->audio_desc));
@@ -78,19 +112,27 @@ SoundAssetWriter::write (float const * const * data, int frames)
                _started = true;
        }
 
+       int const ch = _sound_asset->channels ();
+
        for (int i = 0; i < frames; ++i) {
 
                byte_t* out = _state->frame_buffer.Data() + _frame_buffer_offset;
 
                /* Write one sample per channel */
-               for (int j = 0; j < _sound_asset->channels(); ++j) {
+               for (int j = 0; j < ch; ++j) {
                        /* Convert sample to 24-bit int, clipping if necessary. */
-                       int32_t const s = min (clip, max (-clip, data[j][i])) * (1 << 23);
+                       float x = data[j][i];
+                       if (x > clip) {
+                               x = clip;
+                       } else if (x < -clip) {
+                               x = -clip;
+                       }
+                       int32_t const s = x * (1 << 23);
                        *out++ = (s & 0xff);
                        *out++ = (s & 0xff00) >> 8;
                        *out++ = (s & 0xff0000) >> 16;
                }
-               _frame_buffer_offset += 3 * _sound_asset->channels();
+               _frame_buffer_offset += 3 * ch;
 
                DCP_ASSERT (_frame_buffer_offset <= int (_state->frame_buffer.Capacity()));
 
@@ -106,7 +148,7 @@ SoundAssetWriter::write (float const * const * data, int frames)
 void
 SoundAssetWriter::write_current_frame ()
 {
-       ASDCP::Result_t const r = _state->mxf_writer.WriteFrame (_state->frame_buffer, _encryption_context, _hmac_context);
+       ASDCP::Result_t const r = _state->mxf_writer.WriteFrame (_state->frame_buffer, _encryption_context->encryption(), _encryption_context->hmac());
        if (ASDCP_FAILURE (r)) {
                boost::throw_exception (MiscError (String::compose ("could not write audio MXF frame (%1)", int (r))));
        }