bitstrm.c

au1200 linux2.6.11 硬件解码mae驱动和maiplayer播放器源码

          DPRINTF2((M_TEXT("MPV4: ReadFileMP4() Got data: datasize=%d\n"), BufferInfo.uiDataSize));
          /* BufferProcessed allows compbase to report buffer stats (i.e. for bitrate calculations) */
          MAICompBase_BufferProcessed(g_hComp, BufferInfo.uiDataSize, BufferInfo.uiDataSize); 
          if ((BufferInfo.dwFlags&MAICOMPBUF_FLAG_PTS) != 0)
          {
         // This flag is not defined as of now since the interpolation is not perfect. So, lets use this value (coming from the demux)
#ifndef USE_INTERPOLATED_PTS 
            g_nMP4VPTS = BufferInfo.tTimeStamp;
#endif
            DPRINTF((M_TEXT("MPV4: ReadFileMP4() PTS received, g_nMP4VPTS = %d\n"),g_nMP4VPTS));
          }
          nBytesAvailable += BufferInfo.uiDataSize;
          break; /* don't wait for more data, we've got some now */
        }    
      }
    }

    nTotalBytes = nBytesAvailable;   

#ifdef FAST_LUT_DECODE
    // If we haven't hit EOS yet and the demux returned less than 4 bytes of data,
    // ask for more (since we always need at least 4-bytes of data)
	if (!g_bEOFReached && nBytesAvailable < 5)
		ReadFileMP4();
#endif
    DPRINTF2((M_TEXT("MPV4: ReadFileMP4() done: TotalBytes=%d\n"), nTotalBytes));
}
#endif

#ifdef ENABLE_INTERLACING
INLINE UInt getSingleBit ()
{
	UInt retval = 0;

	if (m_uNumOfBitsInBuffer) 
	{
		 if(m_chDecBuffer&0x80)
			 retval = 1;

    m_chDecBuffer = m_chDecBuffer << 1;
    m_uNumOfBitsInBuffer --;
//        m_lCounter ++;
	}
	else
	{
	if(!nBytesAvailable)
		ReadFileMP4();

#ifdef USE_MAI
//      if (nBytesAvailable)  /* HWG:might be EOS, watch out for negative buffer index! */
#endif
      {
		m_chDecBuffer = MyBuffer[nTotalBytes-nBytesAvailable];
		nBytesAvailable--;

		m_uNumOfBitsInBuffer = 7;
		if(m_chDecBuffer&0x80)
			 retval = 1;
		m_chDecBuffer = m_chDecBuffer << 1;
//		m_lCounter ++;
      }
	}

	return retval;
}
#endif
 
INLINE UInt getBits (UInt numBits)
{
    UInt nGetBitsData = 0;
    Int nLocalBit;

#ifndef NO_ASSERTS
  assert (numBits <= 32);
#endif

    while (numBits) 
    {
        nGetBitsData <<= 1;
        MP4V_RETSINGLEBIT (&nLocalBit);
		nGetBitsData += nLocalBit;
        numBits--;
    }

	return nGetBitsData;
}

#ifdef FAST_LUT_DECODE
INLINE Int peekBits (UInt numBits)
{
	UInt iBitsToRet;
	Int nBitsToPeek, nlocalBytes,nBitsToLoad;

#ifndef NO_ASSERTS
    assert (numBits <= 32);
#endif

	nBitsToPeek = numBits - m_uNumOfBitsInBuffer;
    nlocalBytes = nBytesAvailable;
	if (nBytesAvailable < ((int)numBits>>3))  // JBN 050810
	{
        /* not enough bytes for peek, fill up MyBuffer some more */
         ReadFileMP4();
         nlocalBytes = nBytesAvailable;
	}

	// limit number of bits loaded to min(numBits, m_uNumOfBitsInBuffer) JBN 050809
	nBitsToLoad = (numBits < m_uNumOfBitsInBuffer) ? numBits : m_uNumOfBitsInBuffer;
	iBitsToRet = getbit (nBitsToLoad);
    MP4V_PEEKHELPER(nBitsToPeek, nlocalBytes, &iBitsToRet);
	return iBitsToRet;		
}

INLINE Int peekBitsTillByteAlign (Int *nBitsToPeek) 
{
    *nBitsToPeek = (m_uNumOfBitsInBuffer % 8);

    if (*nBitsToPeek == 0)
        *nBitsToPeek = 8;

    return peekBits(*nBitsToPeek);
}

INLINE Int peekBitsFromByteAlign (Int nBitsToPeek) 
{
	UInt iBitsToRet = 0;

#ifndef NO_ASSERTS
	assert (nBitsToPeek <= 32);
#endif

	if (m_uNumOfBitsInBuffer > 8)
	{
		int iTmpBuff = m_chDecBuffer, iRemainder;

		iRemainder = (m_uNumOfBitsInBuffer % 8);
		if (iRemainder == 0)
			iRemainder = 8;

		iTmpBuff <<= iRemainder;

		iBitsToRet = ((iTmpBuff >> (32 - nBitsToPeek)) & ~(0xFFFFFFFF << nBitsToPeek));
		nBitsToPeek -= (m_uNumOfBitsInBuffer - iRemainder);
	}

	if (nBitsToPeek > 0)
	{
        Int nlocalBytes = nBytesAvailable;
        UInt iBitsToRet1 = 0;

		if (nBytesAvailable < 4)
		{
			ReadFileMP4();
			nlocalBytes = nBytesAvailable;
		}

		if (m_uNumOfBitsInBuffer==0)	
			nlocalBytes--;

		MP4V_PEEKHELPER(nBitsToPeek, nlocalBytes, &iBitsToRet1);
        iBitsToRet |= iBitsToRet1;
	}

	return iBitsToRet;
/*
    // CAUTION!!!! Do not change this condition (don't make it nBytesAvailable < 4)
    if (!nBytesAvailable)
    {
        ReadFileMP4();
        nlocalBytes = nBytesAvailable;
    }

    if (m_uNumOfBitsInBuffer==0)	
        nlocalBytes--;
    else if (m_uNumOfBitsInBuffer>7)
    {
        int iDiv = (m_uNumOfBitsInBuffer/8);

        if (m_uNumOfBitsInBuffer == 8)
            ;
        else if (m_uNumOfBitsInBuffer == 16)
            nlocalBytes+= 1;
        else if (m_uNumOfBitsInBuffer == 24)
            nlocalBytes+= 2;
        else
            nlocalBytes+= iDiv;
    }

    MP4V_PEEKHELPER(nBitsToPeek, nlocalBytes, &iBitsToRet);
	return iBitsToRet;		
*/
}

#else // !FAST_LUT_DECODE

INLINE Int peekBits (UInt numBits)
{
  UInt iBitsToRet;

#ifndef NO_ASSERTS
  assert (numBits <= 32);
#endif
  iBitsToRet = getbit (m_uNumOfBitsInBuffer);
  if (m_uNumOfBitsInBuffer<numBits)
  {
    /* need more buffered data */
    Int nBitsToPeek = numBits - m_uNumOfBitsInBuffer;
    Int nlocalBytes = nBytesAvailable;
    if (!nBytesAvailable)
    {
      ReadFileMP4();
      nlocalBytes = nBytesAvailable;
    }
    iBitsToRet = getbit (m_uNumOfBitsInBuffer);
    MP4V_PEEKHELPER(nBitsToPeek, nlocalBytes, &iBitsToRet);
  }
	return iBitsToRet;		
}

INLINE Int peekBitsTillByteAlign (Int *nBitsToPeek) 
{
#ifndef NO_ASSERTS
	assert (m_uNumOfBitsInBuffer != 8);
#endif
	*nBitsToPeek = (m_uNumOfBitsInBuffer == 0) ? 8 : m_uNumOfBitsInBuffer;

	return peekBits(*nBitsToPeek);
}

INLINE Int peekBitsFromByteAlign (Int nBitsToPeek) 
{
    UInt iBitsToRet = 0;
    Int nlocalBytes = nBytesAvailable;

#ifndef NO_ASSERTS
    assert (nBitsToPeek <= 32);
#endif

    if (!nBytesAvailable)
    {
        ReadFileMP4();
        nlocalBytes = nBytesAvailable;
    }
    
    if (m_uNumOfBitsInBuffer==0)	
        nlocalBytes--;

    MP4V_PEEKHELPER(nBitsToPeek, nlocalBytes, &iBitsToRet);
	return iBitsToRet;		
}
#endif