+ /* XXX: should add on entry point here? */
+ return shared_ptr<const SoundFrame> (new SoundFrame (path().string(), n, _decryption_context));
+}
+
+shared_ptr<SoundAssetWriter>
+SoundAsset::start_write (bool interop, MXFMetadata const & metadata)
+{
+ /* XXX: can't we use a shared_ptr here? */
+ return shared_ptr<SoundAssetWriter> (new SoundAssetWriter (this, interop, metadata));
+}
+
+struct SoundAssetWriter::ASDCPState
+{
+ ASDCP::PCM::MXFWriter mxf_writer;
+ ASDCP::PCM::FrameBuffer frame_buffer;
+ ASDCP::WriterInfo writer_info;
+ ASDCP::PCM::AudioDescriptor audio_desc;
+ ASDCP::AESEncContext* encryption_context;
+};
+
+SoundAssetWriter::SoundAssetWriter (SoundAsset* a, bool interop, MXFMetadata const & m)
+ : _state (new SoundAssetWriter::ASDCPState)
+ , _asset (a)
+ , _finalized (false)
+ , _frames_written (0)
+ , _frame_buffer_offset (0)
+ , _metadata (m)
+{
+ _state->encryption_context = a->encryption_context ();
+
+ /* Derived from ASDCP::Wav::SimpleWaveHeader::FillADesc */
+ _state->audio_desc.EditRate = ASDCP::Rational (_asset->edit_rate(), 1);
+ _state->audio_desc.AudioSamplingRate = ASDCP::Rational (_asset->sampling_rate(), 1);
+ _state->audio_desc.Locked = 0;
+ _state->audio_desc.ChannelCount = _asset->channels ();
+ _state->audio_desc.QuantizationBits = 24;
+ _state->audio_desc.BlockAlign = 3 * _asset->channels();
+ _state->audio_desc.AvgBps = _asset->sampling_rate() * _state->audio_desc.BlockAlign;
+ _state->audio_desc.LinkedTrackID = 0;
+ _state->audio_desc.ChannelFormat = ASDCP::PCM::CF_NONE;
+
+ _state->frame_buffer.Capacity (ASDCP::PCM::CalcFrameBufferSize (_state->audio_desc));
+ _state->frame_buffer.Size (ASDCP::PCM::CalcFrameBufferSize (_state->audio_desc));
+ memset (_state->frame_buffer.Data(), 0, _state->frame_buffer.Capacity());
+
+ _asset->fill_writer_info (&_state->writer_info, _asset->uuid (), interop, _metadata);
+
+ if (ASDCP_FAILURE (_state->mxf_writer.OpenWrite (_asset->path().string().c_str(), _state->writer_info, _state->audio_desc))) {
+ boost::throw_exception (FileError ("could not open audio MXF for writing", _asset->path().string()));
+ }
+}
+
+void
+SoundAssetWriter::write (float const * const * data, int frames)
+{
+ 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 < _asset->channels(); ++j) {
+ int32_t const s = data[j][i] * (1 << 23);
+ *out++ = (s & 0xff);
+ *out++ = (s & 0xff00) >> 8;
+ *out++ = (s & 0xff0000) >> 16;
+ }
+ _frame_buffer_offset += 3 * _asset->channels();
+
+ assert (_frame_buffer_offset <= int (_state->frame_buffer.Capacity()));
+
+ /* Finish the MXF frame if required */
+ if (_frame_buffer_offset == int (_state->frame_buffer.Capacity())) {
+ write_current_frame ();
+ _frame_buffer_offset = 0;
+ memset (_state->frame_buffer.Data(), 0, _state->frame_buffer.Capacity());
+ }
+ }
+}
+
+void
+SoundAssetWriter::write_current_frame ()
+{
+ if (ASDCP_FAILURE (_state->mxf_writer.WriteFrame (_state->frame_buffer, _state->encryption_context, 0))) {
+ boost::throw_exception (MiscError ("could not write audio MXF frame"));
+ }
+
+ ++_frames_written;
+}
+
+void
+SoundAssetWriter::finalize ()
+{
+ if (_frame_buffer_offset > 0) {
+ write_current_frame ();
+ }
+
+ if (ASDCP_FAILURE (_state->mxf_writer.Finalize())) {
+ boost::throw_exception (MiscError ("could not finalise audio MXF"));
+ }
+
+ _finalized = true;
+ _asset->set_intrinsic_duration (_frames_written);
+ _asset->set_duration (_frames_written);
+}
+
+string
+SoundAsset::key_type () const
+{
+ return "MDAK";