umc_mpeg2pes_spl.cpp

这是在PCA下的基于IPP库示例代码例子,在网上下了IPP的库之后,设置相关参数就可以编译该代码.

    {
        ret = m_pDataReader->CheckByte(&byte_code, 0);

        while(byte_code == 0xff && ret == UMC_OK)
        {
            ret = m_pDataReader->GetByte(&byte_code);
             ret = m_pDataReader->CheckByte(&byte_code, 0);
            gotBytes++;
        }

        if((byte_code & 0xc0) == 0x40)
        {
             ret = m_pDataReader->MovePosition(2);
             ret = m_pDataReader->CheckByte(&byte_code, 0);
            gotBytes+=2;
        }
        if((byte_code & 0xf0) == 0x30)
        {
            int c1;
            if((ret = m_pDataReader->GetByte(&byte_code)) != UMC_OK)
                return ret;
            c1 = ((byte_code & 0x0f) >> 1);
            if((ret = m_pDataReader->GetUInt(&ptstmp)) != UMC_OK)
                return ret;
            ptstmp >>= 1;
            ptstmp = (ptstmp & 0x7fff) | (((ptstmp >> 16) & 0x7fff) << 15);
            *out_pts = ((double)ptstmp + (double)(c1 * 1073741824.0)) / 90000.0;
            gotBytes += 5;

            ret = m_pDataReader->MovePosition(5);
            gotBytes += 5;

        }
        else if((byte_code & 0xf0) == 0x20)
        {
            int c1;
            if((ret = m_pDataReader->GetByte(&byte_code)) != UMC_OK)
                return ret;
            c1 = ((byte_code & 0x0f) >> 1);
            if((ret = m_pDataReader->GetUInt(&ptstmp)) != UMC_OK)
                return ret;
            ptstmp >>= 1;
            ptstmp = (ptstmp & 0x7fff) | (((ptstmp >> 16) & 0x7fff) << 15);
            *out_pts = ((double)ptstmp + (double)(c1 * 1073741824.0)) / 90000.0;
            gotBytes += 5;
        }
        else
        {
            if(ret != UMC_OK)
                return ret;
            VM_ASSERT(byte_code == 0x0f);
            ret = m_pDataReader->GetByte(&byte_code);
            gotBytes += 1;
        }
    }

    return ret;
}

int MPEG2PESSplitter::CheckIfNewES(bool isAudio, int streamID, int /*index*/)
{
    int i;
    unsigned char bExist = false;
    for(i = 0; i < m_inESCount; i++)
    {
        if(m_pESArray[i].m_uiStreamID == (unsigned)streamID)
        {
            bExist = true;
            break;
        }
    }
    if(!bExist)
    {
        m_inESCount++;
        m_pESArray[i].m_uiStreamID   = streamID;
        //m_pESArray[i].m_uiStreamSubID; will be re-filled after if available
        if(isAudio)
        {
            if(m_iChoosedAudio[0] == -1)
                m_iChoosedAudio[0]      = streamID;
            else if(m_iChoosedAudio[1] == -1)
                m_iChoosedAudio[1]      = streamID;
        }
        else
        {
            if(m_iChoosedVideo == -1)
                m_iChoosedVideo      = streamID;
        }

    }
    return i;
}


//not sure in this part of code
//exactly know only length of this header 3 bytes
Status MPEG2PESSplitter::ParseAC3PacketHeader(ElementaryStream* pES)
{
    Status err;
    //try to parse, in any case we can skip it
    err = m_pDataReader->MovePosition(3);
    if(err != UMC_OK) return err;

    return err;
}


//not sure in this part of code
//exactly know only length of this header 6 bytes
Status MPEG2PESSplitter::ParseLPCMPacketHeader(ElementaryStream* pES)
{
    Status err;
    //try to parse, in any case we can skip it
    err = m_pDataReader->MovePosition(6);
    if(err != UMC_OK) return err;

    pES->m_audioStreamInfo.bitPerSample = 16;
    pES->m_audioStreamInfo.sample_frequency =  48000;
    pES->m_audioStreamInfo.channels =  2;

    return err;
}

Status MPEG2PESSplitter::GetAudioTime(double* time, double timeStamp)
{
    /*if(curr_audio_pts != -1)
        audio_pts_prev = curr_audio_pts;

    curr_vaudio_pts = timeStamp;

    if(audio_pts_base == -1 && curr_audio_pts != -1)
    {
        audio_pts_base = curr_audio_pts;
    }
    if(audio_pts_base != -1 && curr_audio_pts != -1)
    {

        if(audio_pts_base > curr_audio_pts+1.0)
        {
            audio_pts_base = curr_audio_pts;
            audio_pts_diff = audio_pts_prev;
        }
    }
    if(curr_audio_pts != -1)
        curr_audio_pts += audio_pts_diff;

    curr_audio_time = curr_audio_pts;*/

    *time = timeStamp;

    return UMC_OK;

}

Status MPEG2PESSplitter::GetVideoTime(double* time, double timeStamp)
{

    /*if(m_dCurrVideoPts != -1)
        m_dPrevVideoPts = m_dCurrVideoPts;

    m_dCurrVideoPts = timeStamp;

    if(m_dBaseVideoPts == -1 && m_dCurrVideoPts != -1)
    {
        m_dBaseVideoPts = m_dCurrVideoPts;
    }
    if(m_dBaseVideoPts != -1 && m_dCurrVideoPts != -1)
    {

        if(m_dBaseVideoPts > m_dCurrVideoPts+1.0)
        {
            m_dBaseVideoPts = m_dCurrVideoPts;
            m_dDiffVideoPts = m_dPrevVideoPts;
        }
    }
    if(m_dCurrVideoPts != -1)
        m_dCurrVideoPts += m_dDiffVideoPts;*/



    *time = timeStamp;

    return UMC_OK;

}


Status MPEG2PESSplitter::GetPosition(double& pos)
{
    if(m_pDataReader)
    {
        vm_var64 size      = m_pDataReader->GetSize();
        vm_var64 bitrate   = m_systemStreamInfo.muxrate;
        double dur;

        if(bitrate <= 0)
        {
            bitrate = 700000;
        }

        dur  = ((double)(vm_var64s)(size))/((double)(vm_var64s)(bitrate));
        pos  = (double)dur;

        return UMC_OK;
    }

    return UMC_NOT_INITIALIZED;
}


Status MPEG2PESSplitter::GetInfo(SplitterInfo* pSplInfo)
{
    MPEG2AVSplitter::GetInfo(pSplInfo);

    pSplInfo->m_system_info = m_systemStreamInfo;
     if(m_pDataReader)
    {
        vm_var64 size      = m_pDataReader->GetSize();
        vm_var64 bitrate   = m_systemStreamInfo.muxrate;

        if(bitrate <= 0)
        {
            bitrate = 700000;
        }

        if(pSplInfo->m_video_info.stream_type != UNDEF_VIDEO)
        {
            pSplInfo->m_video_info.duration  =
                    ((double)(vm_var64s)(size))/((double)(vm_var64s)(bitrate));
        }
        if(pSplInfo->m_audio_info.stream_type != UNDEF_AUDIO)
        {
            pSplInfo->m_audio_info.duration  =
                    ((double)(vm_var64s)(size))/((double)(vm_var64s)(bitrate));
        }

    }

    return UMC_OK;
}


Status MPEG2PESSplitter::MPEG2PSPackHeader()
{
    unsigned int  longCode;
    unsigned short shortCode;
    unsigned int  muxRate;
    Status err;

    err = m_pDataReader->CheckUInt(&longCode, 0);
    if(err != UMC_OK) return err;
    if(longCode != ID_PS_PACK_START_CODE)
        return err;

    err = m_pDataReader->GetUInt(&longCode );
    if(err != UMC_OK) return err;


    err = m_pDataReader->GetUInt(&longCode );
    if(err != UMC_OK) return err;

    if(longCode & 0x40000000) // MPEG2 Programm stream
    {
//        vm_sizet size = 0;
        //'01' 2 bits
        //system_clock_reference_base [32..30] 3 bits
        //marker_bit 1 bit
        //system_clock_reference_base [29..15] 15 bits
        //marker_bit 1 bit
        //system_clock_reference_base [14..0] 15 bits
        //marker_bit 1 bit
        //system_clock_reference_extension 9 bits
        //marker_bit 1 bit

        //4 bytes were token befor, need 2 bytes more
        err = m_pDataReader->GetShort(&shortCode );
        if(err != UMC_OK) return err;

        m_systemStreamInfo.stream_type  = MPEG2_PROGRAMM_STREAM;
        //program_mux_rate 22 bits
        //marker_bit 1 bit
        //marker_bit 1 bit
        //reserved   5 bits
        //pack_stuffing_length 3 bits

        err = m_pDataReader->GetUInt(&longCode);
        if(err != UMC_OK) return err;
        muxRate = longCode >> 10;

        m_systemStreamInfo.muxrate  = muxRate*50;//bytes/sec

        //skip stuffing bytes:
        err = m_pDataReader->MovePosition(longCode & 7);
        if(err != UMC_OK) return err;
    }
    else
    {
        if(longCode & 0x20000000) // MPEG1 Prorgamm stream
        {
//            vm_sizet size = 0;
            //'0010'                                    4 bits
            //system_clock_reference [32..30]            3 bits
            //marker_bit                                1 bits
            //system_clock_reference [29..15]            15bits
            //marker_bit                                1 bits
            //system_clock_reference [14..0]            15bits
            //marker_bit                                1 bit
            //marker_bit                                1 bit
            //mux_rate                                    22bits
            //marker_bit                                1 bit

            //4 bytes were token before, need 4 bytes more
            m_systemStreamInfo.stream_type  = MPEG1_PROGRAMM_STREAM;

            err = m_pDataReader->GetUInt(&longCode);
            if(err != UMC_OK) return err;
            muxRate = (longCode >> 1) & 0x003fffff;

            m_systemStreamInfo.muxrate  = muxRate*50;//bytes/sec

        }
        else
            return UMC_BAD_FORMAT;
    }
    err = m_pDataReader->CheckUInt(&longCode, 0);
    if(err != UMC_OK) return err;

    if (longCode == ID_PS_SYSTEM_HEADER_START_CODE)
    {
         //get system header start code
        err = m_pDataReader->GetUInt(&longCode );
        if(err != UMC_OK) return err;

        //err = MPEG2PSSystemHeader();
        //if(err != UMC_OK) return err;

        //Alternate skip system header
        err = m_pDataReader->GetShort(&shortCode);
        if(err != UMC_OK) return err;

        err = m_pDataReader->MovePosition( shortCode);
        if(err != UMC_OK) return err;


    }

    return err;
}