private void ReadImagePlaneHeader(SimpleBitIO bitIO)
{
// internal color format
cfColorFormat = (COLORFORMAT)bitIO.GetBit32_SB(Constant.ColorFormatNumBits);
if (cfColorFormat != COLORFORMAT.Y_ONLY /* accept DEM only! */)
{
throw new ArgumentOutOfRangeException("bitIO", "cfColorFormat = " + cfColorFormat);
}
// lossless mode
bScaledArith = bitIO.GetBit32_SB(Constant.NoScaledFlagNumBits) == 1;
// subbands
sbSubband = (SUBBAND)bitIO.GetBit32_SB(Constant.BandsPresentNumBits);
if (sbSubband != SUBBAND.SB_ALL)
{
throw new ArgumentOutOfRangeException("bitIO", "sbSubband = " + sbSubband);
}
cNumChannels = 1;
bitIO.GetBit32_SB(8); // pSCP->nLenMantissaOrShift = (U8)GetBit32_SB(pSB, 8);
// quantization
uQPMode = 0;
// DC uniform
if (bitIO.GetBit32_SB(Constant.DCFrameUniformNumBits) == 1)
{
uQPMode += (uint)BitstreamDecoder.ReadQuantizerSB(out uiQPIndexDC, bitIO) << 3;
}
else
{
uQPMode++;
}
if (sbSubband != SUBBAND.SB_DC_ONLY)
{
if (bitIO.GetBit32_SB(Constant.UseDCQuantizerNumBits) == 0)
{ // don't use DC QP
uQPMode += 0x200;
if (bitIO.GetBit32_SB(Constant.LPFrameUniformNumBits) == 1) // LP uniform
{
uQPMode += (uint)BitstreamDecoder.ReadQuantizerSB(out uiQPIndexLP, bitIO) << 5;
}
else
{
uQPMode += 2;
}
}
else
{
uQPMode += ((uQPMode & 1) << 1) + ((uQPMode & 0x18) << 2);
}
if (sbSubband != SUBBAND.SB_NO_HIGHPASS)
{
if (bitIO.GetBit32_SB(Constant.UseLPQuantizerNumBits) == 0)
{ // don't use LP QP
uQPMode += 0x400;
if (bitIO.GetBit32_SB(Constant.HPFrameUniformNumBits) == 1) // HP uniform
{
uQPMode += (uint)BitstreamDecoder.ReadQuantizerSB(out uiQPIndexHP, bitIO) << 7;
}
else
{
uQPMode += 4;
}
}
else
{
uQPMode += ((uQPMode & 2) << 1) + ((uQPMode & 0x60) << 2);
}
}
}
if (sbSubband == SUBBAND.SB_DC_ONLY)
{
uQPMode |= 0x200;
}
else
if (sbSubband == SUBBAND.SB_NO_HIGHPASS)
{
uQPMode |= 0x400;
}
if ((uQPMode & 0x600) == 0)
{
throw new ArgumentOutOfRangeException("bitIO", "Frame level QPs must be specified independently!");
}
bitIO.Flush();
}
/// <summary>
/// Reads header of FIRST PLANE only (p.39, HD Photo Bitstream Specification)
/// </summary>
/// <param name="bitIO">Stream to read the image plane header from</param>
private void ReadImagePlaneHeader(SimpleBitIO bitIO)
{
// internal color format
cfColorFormat = (COLORFORMAT)bitIO.GetBit32_SB(Constant.ColorFormatNumBits);
if (cfColorFormat != COLORFORMAT.Y_ONLY /* accept DEM only! */)
{
throw new ArgumentOutOfRangeException("bitIO", "cfColorFormat = " + cfColorFormat);
}
// lossless mode
bScaledArith = bitIO.GetBit32_SB(Constant.NoScaledFlagNumBits) == 1;
// subbands
sbSubband = (SUBBAND)bitIO.GetBit32_SB(Constant.BandsPresentNumBits);
if (sbSubband != SUBBAND.SB_ALL)
{
throw new ArgumentOutOfRangeException("bitIO", "sbSubband = " + sbSubband);
}
cNumChannels = 1;
bitIO.GetBit32_SB(8);// pSCP->nLenMantissaOrShift = (U8)GetBit32_SB(pSB, 8);
// quantization
uQPMode = 0;
// DC uniform
if (bitIO.GetBit32_SB(Constant.DCFrameUniformNumBits) == 1)
{
uQPMode += (uint)BitstreamDecoder.ReadQuantizerSB(out uiQPIndexDC, bitIO) << 3;
}
else
{
uQPMode++;
}
if (sbSubband != SUBBAND.SB_DC_ONLY)
{
if (bitIO.GetBit32_SB(Constant.UseDCQuantizerNumBits) == 0)
{ // don't use DC QP
uQPMode += 0x200;
if (bitIO.GetBit32_SB(Constant.LPFrameUniformNumBits) == 1) // LP uniform
{
uQPMode += (uint)BitstreamDecoder.ReadQuantizerSB(out uiQPIndexLP, bitIO) << 5;
}
else
{
uQPMode += 2;
}
}
else
{
uQPMode += ((uQPMode & 1) << 1) + ((uQPMode & 0x18) << 2);
}
if (sbSubband != SUBBAND.SB_NO_HIGHPASS)
{
if (bitIO.GetBit32_SB(Constant.UseLPQuantizerNumBits) == 0)
{ // don't use LP QP
uQPMode += 0x400;
if (bitIO.GetBit32_SB(Constant.HPFrameUniformNumBits) == 1) // HP uniform
{
uQPMode += (uint)BitstreamDecoder.ReadQuantizerSB(out uiQPIndexHP, bitIO) << 7;
}
else
{
uQPMode += 4;
}
}
else
{
uQPMode += ((uQPMode & 2) << 1) + ((uQPMode & 0x60) << 2);
}
}
}
if (sbSubband == SUBBAND.SB_DC_ONLY)
{
uQPMode |= 0x200;
}
else
if (sbSubband == SUBBAND.SB_NO_HIGHPASS)
{
uQPMode |= 0x400;
}
if ((uQPMode & 0x600) == 0)
{
throw new ArgumentOutOfRangeException("bitIO", "Frame level QPs must be specified independently!");
}
bitIO.Flush();
}
