src/add-ons/media/plugins/ape_reader/MAClib/APECompressCore.cpp

   1 #include "All.h"
   2 #include "APECompressCore.h"
   3
   4 #include "BitArray.h"
   5 #include "Prepare.h"
   6 #include "NewPredictor.h"
   7
   8 CAPECompressCore::CAPECompressCore(CIO * pIO, const WAVEFORMATEX * pwfeInput, int nMaxFrameBlocks, int nCompressionLevel)
   9 {
  10     m_spBitArray.Assign(new CBitArray(pIO));
  11     m_spDataX.Assign(new int [nMaxFrameBlocks], TRUE);
  12     m_spDataY.Assign(new int [nMaxFrameBlocks], TRUE);
  13     m_spTempData.Assign(new int [nMaxFrameBlocks], TRUE);
  14     m_spPrepare.Assign(new CPrepare);
  15     m_spPredictorX.Assign(new CPredictorCompressNormal(nCompressionLevel));
  16     m_spPredictorY.Assign(new CPredictorCompressNormal(nCompressionLevel));
  17
  18     memcpy(&m_wfeInput, pwfeInput, sizeof(WAVEFORMATEX));
  19     m_nPeakLevel = 0;
  20 }
  21
  22 CAPECompressCore::~CAPECompressCore()
  23 {
  24 }
  25
  26 int CAPECompressCore::EncodeFrame(const void * pInputData, int nInputBytes)
  27 {
  28     // variables
  29     const int nInputBlocks = nInputBytes / m_wfeInput.nBlockAlign;
  30     int nSpecialCodes = 0;
  31
  32     // always start a new frame on a byte boundary
  33     m_spBitArray->AdvanceToByteBoundary();
  34
  35     // do the preparation stage
  36     RETURN_ON_ERROR(Prepare(pInputData, nInputBytes, &nSpecialCodes))
  37
  38     m_spPredictorX->Flush();
  39     m_spPredictorY->Flush();
  40
  41     m_spBitArray->FlushState(m_BitArrayStateX);
  42     m_spBitArray->FlushState(m_BitArrayStateY);
  43
  44     m_spBitArray->FlushBitArray();
  45
  46     if (m_wfeInput.nChannels == 2)
  47     {
  48         BOOL bEncodeX = TRUE;
  49         BOOL bEncodeY = TRUE;
  50
  51         if ((nSpecialCodes & SPECIAL_FRAME_LEFT_SILENCE) &&
  52             (nSpecialCodes & SPECIAL_FRAME_RIGHT_SILENCE))
  53         {
  54             bEncodeX = FALSE;
  55             bEncodeY = FALSE;
  56         }
  57
  58         if (nSpecialCodes & SPECIAL_FRAME_PSEUDO_STEREO)
  59         {
  60             bEncodeY = FALSE;
  61         }
  62
  63         if (bEncodeX && bEncodeY)
  64         {
  65             int nLastX = 0;
  66             for (int z = 0; z < nInputBlocks; z++)
  67             {
  68                 m_spBitArray->EncodeValue(m_spPredictorY->CompressValue(m_spDataY[z], nLastX), m_BitArrayStateY);
  69                 m_spBitArray->EncodeValue(m_spPredictorX->CompressValue(m_spDataX[z], m_spDataY[z]), m_BitArrayStateX);
  70
  71                 nLastX = m_spDataX[z];
  72             }
  73         }
  74         else if (bEncodeX)
  75         {
  76             for (int z = 0; z < nInputBlocks; z++)
  77             {
  78                 RETURN_ON_ERROR(m_spBitArray->EncodeValue(m_spPredictorX->CompressValue(m_spDataX[z]), m_BitArrayStateX))
  79             }
  80         }
  81         else if (bEncodeY)
  82         {
  83             for (int z = 0; z < nInputBlocks; z++)
  84             {
  85                 RETURN_ON_ERROR(m_spBitArray->EncodeValue(m_spPredictorY->CompressValue(m_spDataY[z]), m_BitArrayStateY))
  86             }
  87         }
  88     }
  89     else if (m_wfeInput.nChannels == 1)
  90     {
  91         if (!(nSpecialCodes & SPECIAL_FRAME_MONO_SILENCE))
  92         {
  93             for (int z = 0; z < nInputBlocks; z++)
  94             {
  95                 RETURN_ON_ERROR(m_spBitArray->EncodeValue(m_spPredictorX->CompressValue(m_spDataX[z]), m_BitArrayStateX))
  96             }
  97         }
  98     }
  99
 100     m_spBitArray->Finalize();
 101
 102     // return success
 103     return 0;
 104 }
 105
 106 int CAPECompressCore::Prepare(const void * pInputData, int nInputBytes, int * pSpecialCodes)
 107 {
 108     // variable declares
 109     *pSpecialCodes = 0;
 110     unsigned int nCRC = 0;
 111
 112     // do the preparation
 113     RETURN_ON_ERROR(m_spPrepare->Prepare((unsigned char *) pInputData, nInputBytes, &m_wfeInput, m_spDataX, m_spDataY,
 114         &nCRC, pSpecialCodes, &m_nPeakLevel))
 115
 116     // store the CRC
 117     RETURN_ON_ERROR(m_spBitArray->EncodeUnsignedLong(nCRC))
 118
 119     // store any special codes
 120     if (*pSpecialCodes != 0)
 121     {
 122         RETURN_ON_ERROR(m_spBitArray->EncodeUnsignedLong(*pSpecialCodes))
 123     }
 124
 125     return 0;
 126 }