pxpngff.cpp

linux下的一款播放器

                {
                    // Get an IHXBuffer interface from the IHXFragmentedBuffer
                    HX_RELEASE(m_pFileBuffer);
                    retVal = m_pFragBuffer->QueryInterface(IID_IHXBuffer, (void**) &m_pFileBuffer);
                    if (SUCCEEDED(retVal))
                    {
                        // Now we can release the IHXFragmentedBuffer interface
                        HX_RELEASE(m_pFragBuffer);
                        // Set state
                        m_ulState = kStateFileClosePending;
                        // Close the file
                        m_pFileObject->Close();
                    }
                }
                else
                {
                    retVal = HXR_FAIL;
                }
            }
            else
            {
                // Set state
                m_ulState = kStateFileReadPending;
                // Read some more
                m_pFileObject->Read(kReadSize);
            }
        }

        if (FAILED(retVal))
        {
            m_pFormatResponse->InitDone(retVal);
        }
    }
    else
    {
        retVal = HXR_UNEXPECTED;
    }

    return retVal;
}


STDMETHODIMP PXPNGFileFormat::SeekDone(HX_RESULT status)
{
    return HXR_UNEXPECTED;
}

STDMETHODIMP PXPNGFileFormat::CloseDone(HX_RESULT status)
{
    HX_RESULT retVal = HXR_OK;

    if (m_ulState == kStateFileClosePending)
    {
        // Get the width and height out of the IHDR chunk
        if (PXPNGDecode::GetIHDRInfo(m_pFileBuffer, m_ulImageWidth, m_ulImageHeight))
        {
            // Now we have the entire file, so first we determine the number
            // of packets. We do this by finding the beginning of the first
            // IDAT chunk.
            UINT32    ulOffset  = 0;
            UINT32    ulBytes   = 0;
            BOOL      bComplete = FALSE;
            BOOL      bPresent  = PXPNGDecode::IsChunkPresent(m_pFileBuffer,
                                                              0x49444154, // IDAT chunk
                                                              ulOffset,
                                                              ulBytes,
                                                              bComplete);
            if (bPresent && bComplete)
            {
                UINT32 ulFirstBufferSize = 0;
                if (ulOffset + kMinIDATBytes > kDefaultPacketSize)
                {
                    // Since the size of the all the chunks before the IDAT is
                    // greater than the ideal packet size, then we'll just do
                    // the minimum here.
                    ulFirstBufferSize   = ulOffset + kMinIDATBytes;
                }
                else
                {
                    // Since the size of all the chunks before the IDAT is
                    // LESS than the ideal packet size, we'll allow some of
                    // the IDAT chunk into the first packet.
                    ulFirstBufferSize = kDefaultPacketSize;
                    if (ulFirstBufferSize > m_pFileBuffer->GetSize())
                    {
                        ulFirstBufferSize = m_pFileBuffer->GetSize();
                    }
                }
                // Add the first packet buffer
                m_ulNumPacketBuffers  = 1;
                // Add all the rest of the packets past the first
                m_ulNumPacketBuffers += (m_pFileBuffer->GetSize() - ulFirstBufferSize +
                                         kDefaultPacketSize - 1) /
                                         kDefaultPacketSize;
                // So now that we know how many packets we'll have, we
                // can allocate the array of IHXBuffer pointers to hold
                // them.
                HX_VECTOR_DELETE(m_ppPacketBuffer);
                m_ppPacketBuffer = new IHXBuffer* [m_ulNumPacketBuffers];
                if (m_ppPacketBuffer)
                {
                    // Init the statistics
                    m_ulMaxPacketSize = 0;
                    m_ulAvgPacketSize = 0;
                    // Now run through and create the buffers
                    UINT32 ulCurOffset = 0;
                    UINT32 ulCurSize   = ulFirstBufferSize;
                    for (UINT32 i = 0; i < m_ulNumPacketBuffers && SUCCEEDED(retVal); i++)
                    {
                        // Create a nested buffer
                        CHXNestedBuffer* pNest = NULL;
                        retVal                 = CHXNestedBuffer::CreateObject(&pNest);
                        if (SUCCEEDED(retVal))
                        {
                            // AddRef the object
                            pNest->AddRef();
                            // Init the nested buffer
                            retVal = pNest->Init(m_pFileBuffer, ulCurOffset, ulCurSize);
                            if (SUCCEEDED(retVal))
                            {
                                // QI for IHXBuffer
                                IHXBuffer* pData = NULL;
                                retVal            = pNest->QueryInterface(IID_IHXBuffer,
                                                                          (void**) &pData);
                                if (SUCCEEDED(retVal))
                                {
                                    // Update the statistics
                                    if (ulCurSize > m_ulMaxPacketSize)
                                    {
                                        m_ulMaxPacketSize = ulCurSize;
                                    }
                                    m_ulAvgPacketSize += ulCurSize;
                                    // Update the current offset and size
                                    ulCurOffset += ulCurSize;
                                    ulCurSize    = kDefaultPacketSize;
                                    if (ulCurOffset + ulCurSize > m_pFileBuffer->GetSize())
                                    {
                                        ulCurSize = m_pFileBuffer->GetSize() - ulCurOffset;
                                    }
                                    // Put it in the array
                                    m_ppPacketBuffer[i] = pData;
                                    m_ppPacketBuffer[i]->AddRef();
                                }
                                HX_RELEASE(pData);
                            }
                        }
                        HX_RELEASE(pNest);
                    }
                    // Compute the avg
                    m_ulAvgPacketSize    = (m_ulAvgPacketSize + (m_ulNumPacketBuffers >> 1)) /
                                           m_ulNumPacketBuffers;
                    m_ulTotalBytesToSend = m_pFileBuffer->GetSize();
                    // Now we can release the file buffer, since all the
                    // nested buffers have refs on it
                    HX_RELEASE(m_pFileBuffer);
                    // Set the state
                    m_ulState = (SUCCEEDED(retVal) ? kStateFileFormatInitialized : kStateError);
                    // Callback to the response interface
                    m_pFormatResponse->InitDone(retVal);
                }
                else
                {
                    retVal = HXR_OUTOFMEMORY;
                }
            }
            else
            {
                retVal = HXR_FAIL;
            }
        }
        else
        {
            retVal = HXR_FAIL;
        }
    }
    else
    {
        retVal = HXR_UNEXPECTED;
    }

    return retVal;
}

STDMETHODIMP PXPNGFileFormat::WriteDone(HX_RESULT status)
{
    // We don't ever write, so we don't expect to get this...
    return HXR_UNEXPECTED;
}

HX_RESULT STDAPICALLTYPE PXPNGFileFormat::HXCreateInstance(IUnknown** ppIUnknown)
{
    HX_RESULT retVal = HXR_OK;

    if (ppIUnknown)
    {
        // Set default
        *ppIUnknown = NULL;
        // Create the object
        PXPNGFileFormat *pObj = new PXPNGFileFormat();
        if (pObj)
        {
            // QI for IUnknown
            retVal = pObj->QueryInterface(IID_IUnknown, (void**) ppIUnknown);
        }
        else
        {
            retVal = HXR_OUTOFMEMORY;
        }
        if (FAILED(retVal))
        {
            HX_DELETE(pObj);
        }
    }
    else
    {
        retVal = HXR_FAIL;
    }

    return HXR_OK;
}

void PXPNGFileFormat::Deallocate()
{
    for (UINT32 i = 0; i < m_ulNumPacketBuffers; i++)
    {
        HX_RELEASE(m_ppPacketBuffer[i]);
    }
    HX_RELEASE(m_pContext);
    HX_RELEASE(m_pFileObject);
    HX_RELEASE(m_pFormatResponse);
    HX_RELEASE(m_pCommonClassFactory);
    HX_RELEASE(m_pRequest);
    HX_RELEASE(m_pFragBuffer);
    HX_RELEASE(m_pFileBuffer);
    HX_VECTOR_DELETE(m_ppPacketBuffer);
    HX_RELEASE(m_pURLStr);
    Reset();
}

void PXPNGFileFormat::Reset()
{
    m_pContext            = NULL;
    m_pFileObject         = NULL;
    m_pFormatResponse     = NULL;
    m_pCommonClassFactory = NULL;
    m_pRequest            = NULL;
    m_pFragBuffer         = NULL;
    m_ulNumBytesRead      = 0;
    m_pFileBuffer         = NULL;
    m_ulNumPacketBuffers  = 0;
    m_ppPacketBuffer      = NULL;
    m_ulState             = kStateConstructed;
    m_ulDuration          = kDefaultDuration;
    m_ulBitrate           = kDefaultBitrate;
    m_ulImageWidth        = 0;
    m_ulImageHeight       = 0;
    m_pURLStr             = NULL;
    m_bReliable           = FALSE;
    m_ulTotalBytesToSend  = 0;
    m_ulMaxPacketSize     = 0;
    m_ulAvgPacketSize     = 0;
    m_ulBackgroundColor   = 0;
    m_ulNextPacketIndex   = 0;
}

void PXPNGFileFormat::GetURLOrRequestOptions(IHXRequest*     pRequest,
                                             REF(UINT32)      rulDuration,
                                             REF(UINT32)      rulBitrate,
                                             REF(IHXBuffer*) rpURLStr,
                                             REF(BOOL)        rbReliable,
                                             REF(UINT32)      rulBackgroundColor)
{
    if (pRequest && m_pContext && m_pCommonClassFactory)
    {
        // Create an IHXValues object to hold the param name/value pairs
        IHXValues *pValues = NULL;
        m_pCommonClassFactory->CreateInstance(CLSID_IHXValues,
                                              (void**) &pValues);
        if (pValues)
        {
            // Now add the following parameters to the IHXValues. These
            // parameters could have come as URL-encoded parameters or as
            // parameters in the request headers. These parameters will be
            // added as CString properties to the IHXValues.
            AddURLOrRequestParam(pRequest, "duration",                m_pContext, pValues);
            AddURLOrRequestParam(pRequest, "bitrate",                 m_pContext, pValues);
            AddURLOrRequestParam(pRequest, "url",                     m_pContext, pValues);
            AddURLOrRequestParam(pRequest, "reliable",                m_pContext, pValues);
            AddURLOrRequestParam(pRequest, "bgcolor",                 m_pContext, pValues);
            // Set the bitrate
            ExtractValueUINT32(pValues, "bitrate",  kDefaultBitrate,  rulBitrate);
            // Set the duration
            ExtractValueTime(pValues,   "duration", kDefaultDuration, rulDuration);
            // Set the URL
            HX_RELEASE(rpURLStr);
            pValues->GetPropertyCString("url", rpURLStr);
            // Set the background color
            IHXBuffer* pTmp = NULL;
            pValues->GetPropertyCString("bgcolor", pTmp);
            if (pTmp)
            {
                HXParseColorUINT32((const char*) pTmp->GetBuffer(),
                                   rulBackgroundColor);
            }
            HX_RELEASE(pTmp);
            // Set the reliable flag
            ExtractValueBOOL(pValues, "reliable", FALSE, rbReliable);
        }
        // Release the IHXValues object
        HX_RELEASE(pValues);
    }
}