C++ FrameBuffer::Data方法代码示例

  Result_t OpenReadFrame(const char* filename, FrameBuffer& FB)
  {
    ASDCP_TEST_NULL_STR(filename);
    m_File.Close();
    Result_t result = m_File.OpenRead(filename);

    if ( ASDCP_SUCCESS(result) )
    {
        Kumu::fsize_t file_size = m_File.Size();

        if ( FB.Capacity() < file_size )
        {
            DefaultLogSink().Error("FrameBuf.Capacity: %u frame length: %u\n", FB.Capacity(), (ui32_t)file_size);
            return RESULT_SMALLBUF;
        }
    }

    ui32_t read_count;

    if ( ASDCP_SUCCESS(result) )
        result = m_File.Read(FB.Data(), FB.Capacity(), &read_count);

    if ( ASDCP_SUCCESS(result) )
        FB.Size(read_count);

    return result;
  }

ASDCP::Result_t
ASDCP::PCM::AtmosSyncChannelGenerator::ReadFrame(FrameBuffer& OutFB)
{
    if (OutFB.Capacity() < m_numBytesPerFrame)
    {
        return RESULT_SMALLBUF;
    }

    /**
     * Update frame number and size.
     */
    OutFB.FrameNumber(m_currentFrameNumber);
    OutFB.Size(m_numBytesPerFrame);

    /**
     * Get pointer to frame essence.
     */
    byte_t* frameEssence = OutFB.Data();

    if (m_isSyncEncoderInitialized)
    {
        /**
         * Generate sync signal frame.
         */
        int ret = EncodeSync(&m_syncEncoder, m_numSamplesPerFrame, m_syncSignalBuffer, m_currentFrameNumber);
        if (ret == SYNC_ENCODER_ERROR_NONE)
        {
            for (unsigned int i = 0; i < m_numSamplesPerFrame; ++i)
            {
                /**
                 * Convert each encoded float sample to a signed 24 bit integer and
                 * copy into the essence buffer.
                 */
                i32_t sample = convertSampleFloatToInt24(m_syncSignalBuffer[i]);
                memcpy(frameEssence, ((byte_t*)(&sample))+1, NUM_BYTES_PER_INT24);
                frameEssence += NUM_BYTES_PER_INT24;
            }
        }
        else
        {
            /**
             * Encoding error, zero out the frame.
             */
            memset(frameEssence, 0, m_numBytesPerFrame);
        }
    }
    else
    {
        /**
         * Sync encoder not initialize, zero out the frame.
         */
        memset(frameEssence, 0, m_numBytesPerFrame);
    }
    ++m_currentFrameNumber;
    return RESULT_OK;
}

ASDCP::Result_t
ASDCP::MPEG2::Parser::h__Parser::ReadFrame(FrameBuffer& FB)
{
  Result_t result = RESULT_OK;
  ui32_t write_offset = 0;
  ui32_t read_count = 0;

  FB.Size(0);

  if ( m_EOF )
    return RESULT_ENDOFFILE;

  // Data is read in VESReadSize chunks. Each chunk is parsed, and the
  // process is stopped when a Sequence or Picture header is found or when
  // the input file is exhausted. The partial next frame is cached for the
  // next call.
  m_ParserDelegate.Reset();
  m_Parser.Reset();

  if ( m_TmpBuffer.Size() > 0 )
    {
      memcpy(FB.Data(), m_TmpBuffer.RoData(), m_TmpBuffer.Size());
      result = m_Parser.Parse(FB.RoData(), m_TmpBuffer.Size());
      write_offset = m_TmpBuffer.Size();
      m_TmpBuffer.Size(0);
    }

  while ( ! m_ParserDelegate.m_CompletePicture && result == RESULT_OK )
    {
      if ( FB.Capacity() < ( write_offset + VESReadSize ) )
	{
	  DefaultLogSink().Error("FrameBuf.Capacity: %u FrameLength: %u\n",
				 FB.Capacity(), ( write_offset + VESReadSize ));
	  return RESULT_SMALLBUF;
	}

      result = m_FileReader.Read(FB.Data() + write_offset, VESReadSize, &read_count);

      if ( result == RESULT_ENDOFFILE || read_count == 0 )
	{
	  m_EOF = true;

	  if ( write_offset > 0 )
	    result = RESULT_OK;
	}

      if ( ASDCP_SUCCESS(result) )
	{
	  result = m_Parser.Parse(FB.RoData() + write_offset, read_count);
	  write_offset += read_count;
	}

      if ( m_EOF )
	break;
    }
  assert(m_ParserDelegate.m_FrameSize <= write_offset);

  if ( ASDCP_SUCCESS(result)
       && m_ParserDelegate.m_FrameSize < write_offset )
    {
      assert(m_TmpBuffer.Size() == 0);
      ui32_t diff = write_offset - m_ParserDelegate.m_FrameSize;
      assert(diff <= m_TmpBuffer.Capacity());

      memcpy(m_TmpBuffer.Data(), FB.RoData() + m_ParserDelegate.m_FrameSize, diff);
      m_TmpBuffer.Size(diff);
    }

  if ( ASDCP_SUCCESS(result) )
    {
      const byte_t* p = FB.RoData();
      if ( p[0] != 0 || p[1] != 0 || p[2] != 1 || ! ( p[3] == SEQ_START || p[3] == PIC_START ) )
        {
          DefaultLogSink().Error("Frame buffer does not begin with a PIC or SEQ start code.\n");
          return RESULT_RAW_FORMAT;
        }
    }

  if ( ASDCP_SUCCESS(result) )
    {
      FB.Size(m_ParserDelegate.m_FrameSize);
      FB.TemporalOffset(m_ParserDelegate.m_TemporalRef);
      FB.FrameType(m_ParserDelegate.m_FrameType);
      FB.PlaintextOffset(m_ParserDelegate.m_PlaintextOffset);
      FB.FrameNumber(m_FrameNumber++);
      FB.GOPStart(m_ParserDelegate.m_HasGOP);
      FB.ClosedGOP(m_ParserDelegate.m_ClosedGOP);
    }

  return result;
}