bool
NALUnit::Parse(const BYTE* pBuffer, int cSpace, int LengthSize, bool bEnd)
{
// if we get the start code but not the whole
// NALU, we can return false but still have the length property valid
m_cBytes = 0;
ResetBitstream();
if (LengthSize > 0)
{
m_pStartCodeStart = pBuffer;
if (LengthSize > cSpace)
{
return false;
}
m_cBytes = 0;
for (int i = 0; i < LengthSize; i++)
{
m_cBytes <<= 8;
m_cBytes += *pBuffer++;
}
if ((m_cBytes+LengthSize) <= cSpace)
{
m_pStart = pBuffer;
return true;
}
} else {
// this is not length-delimited: we must look for start codes
const BYTE* pBegin;
if (GetStartCode(pBegin, pBuffer, cSpace))
{
m_pStart = pBuffer;
m_pStartCodeStart = pBegin;
// either we find another startcode, or we continue to the
// buffer end (if this is the last block of data)
if (GetStartCode(pBegin, pBuffer, cSpace))
{
m_cBytes = int(pBegin - m_pStart);
return true;
} else if (bEnd)
{
// current element extends to end of buffer
m_cBytes = cSpace;
return true;
}
}
}
return false;
}
bool
NALUnit::Parse(const BYTE* pBuffer, int cSpace, int LengthSize, bool bEnd)
{
m_cBytes = 0;
ResetBitstream();
if (LengthSize > 0)
{
m_pStartCodeStart = pBuffer;
if (LengthSize > cSpace)
{
return false;
}
m_cBytes = 0;
for (int i = 0; i < LengthSize; i++)
{
m_cBytes <<= 8;
m_cBytes += *pBuffer++;
}
if ((m_cBytes+LengthSize) <= cSpace)
{
m_pStart = pBuffer;
return true;
}
} else {
const BYTE* pBegin;
if (GetStartCode(pBegin, pBuffer, cSpace))
{
m_pStart = pBuffer;
m_pStartCodeStart = pBegin;
if (GetStartCode(pBegin, pBuffer, cSpace))
{
m_cBytes = int(pBegin - m_pStart);
return true;
} else if (bEnd)
{
m_cBytes = cSpace;
return true;
}
}
}
return false;
}
///////////////////////////////////////////////////////////////////////////////
// Function: Demux_ul
// Returns: The number of bytes processed
///////////////////////////////////////////////////////////////////////////////
UINT32 CDemuxer::Demux_ul(UINT8 *pBuffer,
UINT32 ulBytes,
Packet *pPacket)
{
UINT8 *pTemp = (UINT8*)pBuffer;
UINT32 ulTemp = ulBytes;
INT32 lCode = 0;
memset(pPacket, 0, sizeof(Packet));
UINT8 bCont = TRUE;
while (ulTemp >= 4 && bCont)
{
lCode = GetStartCode(&pTemp, ulTemp);
switch (lCode)
{
case -1:
bCont = FALSE;
break;
case PACK_HEADER:
{
m_pPack = pTemp;
pTemp+=4;
ulTemp-=4;
// Is this MPEG1 or MPEG2
UINT8 yNext = *pTemp & 0xF0;
// Check for MPEG1 or MPEG2.
// In MPEG2 files, '0100' follows pack_start_code and
// in MPEG1 files, '0010' follows pack_start_code.
if ((yNext & 0xC0) == 0x40)
m_bMPEG2 = TRUE;
else
m_bMPEG2 = FALSE;
break;
}
default:
// PRIVATE_STREAM_1
// VIDEO_PACKET
// AUDIO_PACKET
if ( PRIVATE_STREAM_1 == lCode ||
(lCode & 0x000000F0) == 0xE0 ||
(lCode & 0x000000E0) == 0xC0)
{
if (ProcessPacket(&pTemp, ulTemp, pPacket))
{
bCont = FALSE;
}
}
else
{
pTemp+=4;
ulTemp-=4;
}
break;
}
}
return (UINT32)(PTR_INT)(pTemp - pBuffer);
}
