AS_DCP_PCM.cpp

/*
Copyright (c) 2004-2021, John Hurst
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/*! \file    AS_DCP_PCM.cpp
    \version $Id$       
    \brief   AS-DCP library, PCM essence reader and writer implementation
*/

#include "AS_DCP_internal.h"
#include <map>
#include <iostream>
#include <iomanip>

//------------------------------------------------------------------------------------------

static std::string PCM_PACKAGE_LABEL = "File Package: SMPTE 382M frame wrapping of wave audio";
static std::string SOUND_DEF_LABEL = "Sound Track";

//
Result_t
ASDCP::PCM_ADesc_to_MD(PCM::AudioDescriptor& ADesc, MXF::WaveAudioDescriptor* ADescObj)
{
  ASDCP_TEST_NULL(ADescObj);
  ADescObj->SampleRate = ADesc.EditRate;
  ADescObj->AudioSamplingRate = ADesc.AudioSamplingRate;
  ADescObj->Locked = ADesc.Locked;
  ADescObj->ChannelCount = ADesc.ChannelCount;
  ADescObj->QuantizationBits = ADesc.QuantizationBits;
  ADescObj->BlockAlign = ADesc.BlockAlign;
  ADescObj->AvgBps = ADesc.AvgBps;
  ADescObj->LinkedTrackID = ADesc.LinkedTrackID;
  ADescObj->ContainerDuration = ADesc.ContainerDuration;
  ADescObj->ChannelAssignment.get().Reset();

  switch ( ADesc.ChannelFormat )
    {
      case PCM::CF_CFG_1:
	ADescObj->ChannelAssignment = DefaultSMPTEDict().Type(MDD_DCAudioChannelCfg_1_5p1).ul;
	break;

      case PCM::CF_CFG_2:
	ADescObj->ChannelAssignment = DefaultSMPTEDict().Type(MDD_DCAudioChannelCfg_2_6p1).ul;
	break;

      case PCM::CF_CFG_3:
	ADescObj->ChannelAssignment = DefaultSMPTEDict().Type(MDD_DCAudioChannelCfg_3_7p1).ul;
	break;

      case PCM::CF_CFG_4:
	ADescObj->ChannelAssignment = DefaultSMPTEDict().Type(MDD_DCAudioChannelCfg_4_WTF).ul;
	break;

      case PCM::CF_CFG_5:
	ADescObj->ChannelAssignment = DefaultSMPTEDict().Type(MDD_DCAudioChannelCfg_5_7p1_DS).ul;
	break;

      case PCM::CF_CFG_6:
	ADescObj->ChannelAssignment = DefaultSMPTEDict().Type(MDD_DCAudioChannelCfg_MCA).ul;
	break;

      case PCM::CF_NONE:
      case PCM::CF_MAXIMUM:
	break;
    }

  return RESULT_OK;
}

//
ASDCP::Result_t
ASDCP::MD_to_PCM_ADesc(MXF::WaveAudioDescriptor* ADescObj, PCM::AudioDescriptor& ADesc)
{
  ASDCP_TEST_NULL(ADescObj);
  ADesc.EditRate = ADescObj->SampleRate;
  ADesc.AudioSamplingRate = ADescObj->AudioSamplingRate;
  ADesc.Locked = ADescObj->Locked;
  ADesc.ChannelCount = ADescObj->ChannelCount;
  ADesc.QuantizationBits = ADescObj->QuantizationBits;
  ADesc.BlockAlign = ADescObj->BlockAlign;
  ADesc.AvgBps = ADescObj->AvgBps;
  if ( ! ADescObj->LinkedTrackID.empty() )
    {
      ADesc.LinkedTrackID = ADescObj->LinkedTrackID;
    }
  if ( ! ADescObj->ContainerDuration.empty() )
    {
      assert(ADescObj->ContainerDuration <= 0xFFFFFFFFL);
      ADesc.ContainerDuration = (ui32_t) ADescObj->ContainerDuration;
    }
  ADesc.ChannelFormat = PCM::CF_NONE;

  if ( ! ADescObj->ChannelAssignment.empty() )
    {
      if ( ADescObj->ChannelAssignment == DefaultSMPTEDict().Type(MDD_DCAudioChannelCfg_1_5p1).ul )
	ADesc.ChannelFormat = PCM::CF_CFG_1;

      else if ( ADescObj->ChannelAssignment == DefaultSMPTEDict().Type(MDD_DCAudioChannelCfg_2_6p1).ul )
	ADesc.ChannelFormat = PCM::CF_CFG_2;

      else if ( ADescObj->ChannelAssignment == DefaultSMPTEDict().Type(MDD_DCAudioChannelCfg_3_7p1).ul )
	ADesc.ChannelFormat = PCM::CF_CFG_3;

      else if ( ADescObj->ChannelAssignment == DefaultSMPTEDict().Type(MDD_DCAudioChannelCfg_4_WTF).ul )
	ADesc.ChannelFormat = PCM::CF_CFG_4;

      else if ( ADescObj->ChannelAssignment == DefaultSMPTEDict().Type(MDD_DCAudioChannelCfg_5_7p1_DS).ul )
	ADesc.ChannelFormat = PCM::CF_CFG_5;

      else if ( ADescObj->ChannelAssignment == DefaultSMPTEDict().Type(MDD_DCAudioChannelCfg_MCA).ul )
	ADesc.ChannelFormat = PCM::CF_CFG_6;
    }

  return RESULT_OK;
}

//
std::ostream&
ASDCP::PCM::operator << (std::ostream& strm, const AudioDescriptor& ADesc)
{
  strm << "        SampleRate: " << ADesc.EditRate.Numerator << "/" << ADesc.EditRate.Denominator << std::endl;
  strm << " AudioSamplingRate: " << ADesc.AudioSamplingRate.Numerator << "/" << ADesc.AudioSamplingRate.Denominator << std::endl;
  strm << "            Locked: " << (unsigned) ADesc.Locked << std::endl;
  strm << "      ChannelCount: " << (unsigned) ADesc.ChannelCount << std::endl;
  strm << "  QuantizationBits: " << (unsigned) ADesc.QuantizationBits << std::endl;
  strm << "        BlockAlign: " << (unsigned) ADesc.BlockAlign << std::endl;
  strm << "            AvgBps: " << (unsigned) ADesc.AvgBps << std::endl;
  strm << "     LinkedTrackID: " << (unsigned) ADesc.LinkedTrackID << std::endl;
  strm << " ContainerDuration: " << (unsigned) ADesc.ContainerDuration << std::endl;
  strm << "     ChannelFormat: ";
  switch (ADesc.ChannelFormat)
  {
    case CF_NONE:
    default:
      strm << "No Channel Format";
      break;

    case CF_CFG_1:
      strm << "Config 1 (5.1 with optional HI/VI)";
      break;

    case CF_CFG_2:
      strm << "Config 2 (5.1 + center surround with optional HI/VI)";
      break;

    case CF_CFG_3:
      strm << "Config 3 (7.1 with optional HI/VI)";
      break;

    case CF_CFG_4:
      strm << "Config 4";
      break;

    case CF_CFG_5:
      strm << "Config 5 (7.1 DS with optional HI/VI)";
      break;

    case CF_CFG_6:
      strm << "Config 6 (ST 377-4 MCA)";
      break;
  }
  strm << std::endl;

  return strm;
}

//
void
ASDCP::PCM::AudioDescriptorDump(const AudioDescriptor& ADesc, FILE* stream)
{
  if ( stream == 0 )
    stream = stderr;

  fprintf(stream, "\
        EditRate: %d/%d\n\
 AudioSamplingRate: %d/%d\n\
            Locked: %u\n\
      ChannelCount: %u\n\
  QuantizationBits: %u\n\
        BlockAlign: %u\n\
            AvgBps: %u\n\
     LinkedTrackID: %u\n\
 ContainerDuration: %u\n\
     ChannelFormat: %u\n",
	  ADesc.EditRate.Numerator, ADesc.EditRate.Denominator,
	  ADesc.AudioSamplingRate.Numerator, ADesc.AudioSamplingRate.Denominator,
	  ADesc.Locked,
	  ADesc.ChannelCount,
	  ADesc.QuantizationBits,
	  ADesc.BlockAlign,
	  ADesc.AvgBps,
	  ADesc.LinkedTrackID,
	  ADesc.ContainerDuration,
          ADesc.ChannelFormat
	  );
}


//
//
static ui32_t
calc_CBR_frame_size(ASDCP::WriterInfo& Info, const ASDCP::PCM::AudioDescriptor& ADesc)
{
  ui32_t CBR_frame_size = 0;

  if ( Info.EncryptedEssence )
    {
      CBR_frame_size =
	SMPTE_UL_LENGTH
	+ MXF_BER_LENGTH
	+ klv_cryptinfo_size
	+ calc_esv_length(ASDCP::PCM::CalcFrameBufferSize(ADesc), 0)
	+ ( Info.UsesHMAC ? klv_intpack_size : (MXF_BER_LENGTH * 3) );
    }
  else
    {
      CBR_frame_size = ASDCP::PCM::CalcFrameBufferSize(ADesc) + SMPTE_UL_LENGTH + MXF_BER_LENGTH;
    }

  return CBR_frame_size;
}


//------------------------------------------------------------------------------------------


class ASDCP::PCM::MXFReader::h__Reader : public ASDCP::h__ASDCPReader
{
  ASDCP_NO_COPY_CONSTRUCT(h__Reader);
  h__Reader();

public:
  AudioDescriptor m_ADesc;

  h__Reader(const Dictionary *d, const Kumu::IFileReaderFactory& fileReaderFactory) : ASDCP::h__ASDCPReader(d, fileReaderFactory) {}
  virtual ~h__Reader() {}
  Result_t    OpenRead(const std::string&);
  Result_t    ReadFrame(ui32_t, FrameBuffer&, AESDecContext*, HMACContext*);
};


//
//
ASDCP::Result_t
ASDCP::PCM::MXFReader::h__Reader::OpenRead(const std::string& filename)
{
  Result_t result = OpenMXFRead(filename);

  if( ASDCP_SUCCESS(result) )
    {
      InterchangeObject* Object = 0
;
      if ( ASDCP_SUCCESS(m_HeaderPart.GetMDObjectByType(OBJ_TYPE_ARGS(WaveAudioDescriptor), &Object)) )
	{
	  if ( Object == 0 )
	    {
	      DefaultLogSink().Error("WaveAudioDescriptor object not found.\n");
	      return RESULT_FORMAT;
	    }

	  result = MD_to_PCM_ADesc((MXF::WaveAudioDescriptor*)Object, m_ADesc);
	}
    }

  if ( m_ADesc.ContainerDuration == 0 )
    {
      DefaultLogSink().Error("ContainerDuration unset.\n");
      return RESULT_FORMAT;
    }

  // check for sample/frame rate sanity
  if ( ASDCP_SUCCESS(result)
       && m_ADesc.EditRate != EditRate_24
       && m_ADesc.EditRate != EditRate_25
       && m_ADesc.EditRate != EditRate_30
       && m_ADesc.EditRate != EditRate_48
       && m_ADesc.EditRate != EditRate_50
       && m_ADesc.EditRate != EditRate_60
       && m_ADesc.EditRate != EditRate_96
       && m_ADesc.EditRate != EditRate_100
       && m_ADesc.EditRate != EditRate_120
       && m_ADesc.EditRate != EditRate_192
       && m_ADesc.EditRate != EditRate_200
       && m_ADesc.EditRate != EditRate_240
       && m_ADesc.EditRate != EditRate_16
       && m_ADesc.EditRate != EditRate_18
       && m_ADesc.EditRate != EditRate_20
       && m_ADesc.EditRate != EditRate_22
       && m_ADesc.EditRate != EditRate_23_98 )
    {
      DefaultLogSink().Error("PCM file EditRate is not a supported value: %d/%d\n", // lu
			     m_ADesc.EditRate.Numerator, m_ADesc.EditRate.Denominator);

      // oh, they gave us the audio sampling rate instead, assume 24/1
      if ( m_ADesc.EditRate == SampleRate_48k || m_ADesc.EditRate == SampleRate_96k )
	{
	  DefaultLogSink().Warn("adjusting EditRate to 24/1\n"); 
	  m_ADesc.EditRate = EditRate_24;
	}
      else
	{
	  DefaultLogSink().Error("PCM EditRate not in expected value range.\n");
	  // or we just drop the hammer
	  return RESULT_FORMAT;
	}
    }

  // TODO: test file for sane CBR index BytesPerEditUnit

  return result;
}


//
//
ASDCP::Result_t
ASDCP::PCM::MXFReader::h__Reader::ReadFrame(ui32_t FrameNum, FrameBuffer& FrameBuf,
					    AESDecContext* Ctx, HMACContext* HMAC)
{
  if ( ! m_File->IsOpen() )
    return RESULT_INIT;

  if ( (FrameNum+1) > m_ADesc.ContainerDuration )
    {
      return RESULT_RANGE;
    }

  assert(m_Dict);
  return ReadEKLVFrame(FrameNum, FrameBuf, m_Dict->ul(MDD_WAVEssence), Ctx, HMAC);
}

//------------------------------------------------------------------------------------------


//
void
ASDCP::PCM::FrameBuffer::Dump(FILE* stream, ui32_t dump_len) const
{
  if ( stream == 0 )
    stream = stderr;

  fprintf(stream, "Frame: %06u, %7u bytes\n",
	  m_FrameNumber, m_Size);

  if ( dump_len )
    Kumu::hexdump(m_Data, dump_len, stream);
}

//------------------------------------------------------------------------------------------

ASDCP::PCM::MXFReader::MXFReader(const Kumu::IFileReaderFactory& fileReaderFactory)
{
  m_Reader = new h__Reader(&DefaultCompositeDict(), fileReaderFactory);
}


ASDCP::PCM::MXFReader::~MXFReader()
{
  if ( m_Reader && m_Reader->m_File->IsOpen() )
    m_Reader->Close();
}

// Warning: direct manipulation of MXF structures can interfere
// with the normal operation of the wrapper.  Caveat emptor!
//
ASDCP::MXF::OP1aHeader&
ASDCP::PCM::MXFReader::OP1aHeader()
{
  if ( m_Reader.empty() )
    {
      assert(g_OP1aHeader);
      return *g_OP1aHeader;
    }

  return m_Reader->m_HeaderPart;
}

// Warning: direct manipulation of MXF structures can interfere
// with the normal operation of the wrapper.  Caveat emptor!
//
ASDCP::MXF::OPAtomIndexFooter&
ASDCP::PCM::MXFReader::OPAtomIndexFooter()
{
  if ( m_Reader.empty() )
    {
      assert(g_OPAtomIndexFooter);
      return *g_OPAtomIndexFooter;
    }

  return m_Reader->m_IndexAccess;
}

// Warning: direct manipulation of MXF structures can interfere
// with the normal operation of the wrapper.  Caveat emptor!
//
ASDCP::MXF::RIP&
ASDCP::PCM::MXFReader::RIP()
{
  if ( m_Reader.empty() )
    {
      assert(g_RIP);
      return *g_RIP;
    }

  return m_Reader->m_RIP;
}

// Open the file for reading. The file must exist. Returns error if the
// operation cannot be completed.
ASDCP::Result_t
ASDCP::PCM::MXFReader::OpenRead(const std::string& filename) const
{
  return m_Reader->OpenRead(filename);
}

// Reads a frame of essence from the MXF file. If the optional AESEncContext
// argument is present, the essence is decrypted after reading. If the MXF
// file is encrypted and the AESDecContext argument is NULL, the frame buffer
// will contain the ciphertext frame data.
ASDCP::Result_t
ASDCP::PCM::MXFReader::ReadFrame(ui32_t FrameNum, FrameBuffer& FrameBuf,
				 AESDecContext* Ctx, HMACContext* HMAC) const
{
  if ( m_Reader && m_Reader->m_File->IsOpen() )
    return m_Reader->ReadFrame(FrameNum, FrameBuf, Ctx, HMAC);

  return RESULT_INIT;
}


ASDCP::Result_t
ASDCP::PCM::MXFReader::LocateFrame(ui32_t FrameNum, Kumu::fpos_t& streamOffset, i8_t& temporalOffset, i8_t& keyFrameOffset) const
{
    return m_Reader->LocateFrame(FrameNum, streamOffset, temporalOffset, keyFrameOffset);
}

// Fill the struct with the values from the file's header.
// Returns RESULT_INIT if the file is not open.
ASDCP::Result_t
ASDCP::PCM::MXFReader::FillAudioDescriptor(AudioDescriptor& ADesc) const
{
  if ( m_Reader && m_Reader->m_File->IsOpen() )
    {
      ADesc = m_Reader->m_ADesc;
      return RESULT_OK;
    }

  return RESULT_INIT;
}

// Fill the struct with the values from the file's header.
// Returns RESULT_INIT if the file is not open.
ASDCP::Result_t
ASDCP::PCM::MXFReader::FillWriterInfo(WriterInfo& Info) const
{
  if ( m_Reader && m_Reader->m_File->IsOpen() )
    {
      Info = m_Reader->m_Info;
      return RESULT_OK;
    }

  return RESULT_INIT;
}

//
void
ASDCP::PCM::MXFReader::DumpHeaderMetadata(FILE* stream) const
{
  if ( m_Reader && m_Reader->m_File->IsOpen() )
    m_Reader->m_HeaderPart.Dump(stream);
}


//
void
ASDCP::PCM::MXFReader::DumpIndex(FILE* stream) const
{
  if ( m_Reader->m_File->IsOpen() )
    m_Reader->m_IndexAccess.Dump(stream);
}

//
ASDCP::Result_t
ASDCP::PCM::MXFReader::Close() const
{
  if ( m_Reader && m_Reader->m_File->IsOpen() )
    {
      m_Reader->Close();
      return RESULT_OK;
    }

  return RESULT_INIT;
}


//------------------------------------------------------------------------------------------

//
class ASDCP::PCM::MXFWriter::h__Writer : public ASDCP::h__ASDCPWriter
{
  ASDCP_NO_COPY_CONSTRUCT(h__Writer);
  h__Writer();

public:
  AudioDescriptor m_ADesc;
  byte_t          m_EssenceUL[SMPTE_UL_LENGTH];
  
  h__Writer(const Dictionary *d) : ASDCP::h__ASDCPWriter(d) {
    memset(m_EssenceUL, 0, SMPTE_UL_LENGTH);
  }

  virtual ~h__Writer(){}

  Result_t OpenWrite(const std::string&, ui32_t HeaderSize);
  Result_t SetSourceStream(const AudioDescriptor&);
  Result_t WriteFrame(const FrameBuffer&, AESEncContext* = 0, HMACContext* = 0);
  Result_t Finalize();
};



// Open the file for writing. The file must not exist. Returns error if
// the operation cannot be completed.
ASDCP::Result_t
ASDCP::PCM::MXFWriter::h__Writer::OpenWrite(const std::string& filename, ui32_t HeaderSize)
{
  if ( ! m_State.Test_BEGIN() )
    return RESULT_STATE;

  Result_t result = m_File.OpenWrite(filename);

  if ( ASDCP_SUCCESS(result) )
    {
      m_HeaderSize = HeaderSize;
      m_EssenceDescriptor = new WaveAudioDescriptor(m_Dict);
      result = m_State.Goto_INIT();
    }

  return result;
}


// Automatically sets the MXF file's metadata from the WAV parser info.
ASDCP::Result_t
ASDCP::PCM::MXFWriter::h__Writer::SetSourceStream(const AudioDescriptor& ADesc)
{
  if ( ! m_State.Test_INIT() )
    return RESULT_STATE;

  if ( ADesc.EditRate != EditRate_24
       && ADesc.EditRate != EditRate_25
       && ADesc.EditRate != EditRate_30
       && ADesc.EditRate != EditRate_48
       && ADesc.EditRate != EditRate_50
       && ADesc.EditRate != EditRate_60
       && ADesc.EditRate != EditRate_96
       && ADesc.EditRate != EditRate_100
       && ADesc.EditRate != EditRate_120
       && ADesc.EditRate != EditRate_192
       && ADesc.EditRate != EditRate_200
       && ADesc.EditRate != EditRate_240
       && ADesc.EditRate != EditRate_16
       && ADesc.EditRate != EditRate_18
       && ADesc.EditRate != EditRate_20
       && ADesc.EditRate != EditRate_22
       && ADesc.EditRate != EditRate_23_98 )
    {
      DefaultLogSink().Error("AudioDescriptor.EditRate is not a supported value: %d/%d\n",
			     ADesc.EditRate.Numerator, ADesc.EditRate.Denominator);
      return RESULT_RAW_FORMAT;
    }

  if ( ADesc.AudioSamplingRate != SampleRate_48k && ADesc.AudioSamplingRate != SampleRate_96k )
    {
      DefaultLogSink().Error("AudioDescriptor.AudioSamplingRate is not 48000/1 or 96000/1: %d/%d\n",
			     ADesc.AudioSamplingRate.Numerator, ADesc.AudioSamplingRate.Denominator);
      return RESULT_RAW_FORMAT;
    }

  assert(m_Dict);
  m_ADesc = ADesc;

  Result_t result = PCM_ADesc_to_MD(m_ADesc, (WaveAudioDescriptor*)m_EssenceDescriptor);
  
  if ( ASDCP_SUCCESS(result) )
    {
      memcpy(m_EssenceUL, m_Dict->ul(MDD_WAVEssence), SMPTE_UL_LENGTH);
      m_EssenceUL[SMPTE_UL_LENGTH-1] = 1; // first (and only) essence container
      result = m_State.Goto_READY();
    }

  if ( ASDCP_SUCCESS(result) )
    {
      result = WriteASDCPHeader(PCM_PACKAGE_LABEL, UL(m_Dict->ul(MDD_WAVWrappingFrame)),
				SOUND_DEF_LABEL, UL(m_EssenceUL), UL(m_Dict->ul(MDD_SoundDataDef)),
				m_ADesc.EditRate, derive_timecode_rate_from_edit_rate(m_ADesc.EditRate),
				calc_CBR_frame_size(m_Info, m_ADesc));
    }

  return result;
}


//
//
ASDCP::Result_t
ASDCP::PCM::MXFWriter::h__Writer::WriteFrame(const FrameBuffer& FrameBuf, AESEncContext* Ctx,
					     HMACContext* HMAC)
{
  Result_t result = RESULT_OK;

  if ( m_State.Test_READY() )
    result = m_State.Goto_RUNNING(); // first time through

  if ( ASDCP_SUCCESS(result) )
    result = WriteEKLVPacket(FrameBuf, m_EssenceUL, MXF_BER_LENGTH, Ctx, HMAC);

  if ( ASDCP_SUCCESS(result) )
    m_FramesWritten++;

  return result;
}

// Closes the MXF file, writing the index and other closing information.
//
ASDCP::Result_t
ASDCP::PCM::MXFWriter::h__Writer::Finalize()
{
  if ( ! m_State.Test_RUNNING() )
    return RESULT_STATE;

  m_State.Goto_FINAL();

  return WriteASDCPFooter();
}


//------------------------------------------------------------------------------------------
//



ASDCP::PCM::MXFWriter::MXFWriter()
{
}

ASDCP::PCM::MXFWriter::~MXFWriter()
{
}

// Warning: direct manipulation of MXF structures can interfere
// with the normal operation of the wrapper.  Caveat emptor!
//
ASDCP::MXF::OP1aHeader&
ASDCP::PCM::MXFWriter::OP1aHeader()
{
  if ( m_Writer.empty() )
    {
      assert(g_OP1aHeader);
      return *g_OP1aHeader;
    }

  return m_Writer->m_HeaderPart;
}

// Warning: direct manipulation of MXF structures can interfere
// with the normal operation of the wrapper.  Caveat emptor!
//
ASDCP::MXF::OPAtomIndexFooter&
ASDCP::PCM::MXFWriter::OPAtomIndexFooter()
{
  if ( m_Writer.empty() )
    {
      assert(g_OPAtomIndexFooter);
      return *g_OPAtomIndexFooter;
    }

  return m_Writer->m_FooterPart;
}

// Warning: direct manipulation of MXF structures can interfere
// with the normal operation of the wrapper.  Caveat emptor!
//
ASDCP::MXF::RIP&
ASDCP::PCM::MXFWriter::RIP()
{
  if ( m_Writer.empty() )
    {
      assert(g_RIP);
      return *g_RIP;
    }

  return m_Writer->m_RIP;
}

// Open the file for writing. The file must not exist. Returns error if
// the operation cannot be completed.
ASDCP::Result_t
ASDCP::PCM::MXFWriter::OpenWrite(const std::string& filename, const WriterInfo& Info,
				 const AudioDescriptor& ADesc, ui32_t HeaderSize)
{
  if ( Info.LabelSetType == LS_MXF_SMPTE )
    m_Writer = new h__Writer(&DefaultSMPTEDict());
  else
    m_Writer = new h__Writer(&DefaultInteropDict());

  m_Writer->m_Info = Info;
  
  Result_t result = m_Writer->OpenWrite(filename, HeaderSize);

  if ( ASDCP_SUCCESS(result) )
    result = m_Writer->SetSourceStream(ADesc);

  if ( ASDCP_FAILURE(result) )
    m_Writer.release();

  return result;
}

// Writes a frame of essence to the MXF file. If the optional AESEncContext
// argument is present, the essence is encrypted prior to writing.
// Fails if the file is not open, is finalized, or an operating system
// error occurs.
ASDCP::Result_t
ASDCP::PCM::MXFWriter::WriteFrame(const FrameBuffer& FrameBuf, AESEncContext* Ctx, HMACContext* HMAC)
{
  if ( m_Writer.empty() )
    return RESULT_INIT;

  return m_Writer->WriteFrame(FrameBuf, Ctx, HMAC);
}

// Closes the MXF file, writing the index and other closing information.
ASDCP::Result_t
ASDCP::PCM::MXFWriter::Finalize()
{
  if ( m_Writer.empty() )
    return RESULT_INIT;

  return m_Writer->Finalize();
}

//
// end AS_DCP_PCM.cpp
//