如何在MF應用程序中使用幀速率轉換器DMO

我希望在我的媒體基礎應用程序中使用Frame Rate convertor DSP。我正在使用'SourceReader'來讀取視頻文件。任何人都可以告訴我在哪裏以及如何整合DMO與MF來獲得幀率轉換。我似乎無法理解向DMO提供哪種樣本（壓縮/未壓縮）以獲得新的幀速率。 DMO如何改變幀速率？它是否爲新樣本提供了新的時間戳？沒有代碼示例演示其用法。請幫助，我卡住了。如何在MF應用程序中使用幀速率轉換器DMO

感謝，磁光阱

來源

2011-12-07 mots_g

這是一個老問題。

要使用SourceReader進行幀速率轉換，我們需要手動集成DMO。

這個想法是從SourceReader獲得兼容的樣本，比如說由DMO處理的視頻子類型。

DMO如何改變幀速率？

根據幀速率轉換器的DSP：

該DSP改變通過重複或丟棄幀的幀速率。

。

它是否給新樣本添加新的時間戳？

DMO更改採樣時間和採樣持續時間。但是，如果視頻文件的持續時間是1分鐘，那末它將保持不變。

例如，如果您的視頻文件有1800幀，持續時間爲1分鐘，幀速率爲30幀/秒。你想要60幀/秒，所以你將有3600幀，持續時間不會改變（總是1分鐘）。

#pragma once 
#define WIN32_LEAN_AND_MEAN 
#define STRICT 

#pragma comment(lib, "mfplat") 
#pragma comment(lib, "mfreadwrite") 
#pragma comment(lib, "mfuuid") 
#pragma comment(lib, "wmcodecdspuuid") 

#include <WinSDKVer.h> 
#include <new> 
#include <windows.h> 
#include <mfapi.h> 
#include <mfidl.h> 
#include <mfreadwrite.h> 
#include <mferror.h> 
#include <Wmcodecdsp.h> 

template <class T> inline void SAFE_RELEASE(T*& p){ 

    if(p){ 
     p->Release(); 
     p = NULL; 
    } 
} 

HRESULT ProcessConverter(); 
HRESULT InitDMO(IMFTransform**, IMFMediaType*); 
HRESULT ProcessSample(IMFSourceReader*, IMFTransform*); 
HRESULT ProcessDMO(IMFTransform*, IMFSample*, DWORD&, const UINT32); 
HRESULT InitOutputDataBuffer(IMFTransform*, MFT_OUTPUT_DATA_BUFFER*, const UINT32); 

void main(){ 

    HRESULT hr = CoInitializeEx(NULL, COINIT_APARTMENTTHREADED | COINIT_DISABLE_OLE1DDE); 

    if(SUCCEEDED(hr)){ 

     hr = MFStartup(MF_VERSION, MFSTARTUP_LITE); 

     if(SUCCEEDED(hr)){ 

      hr = ProcessConverter(); 

      hr = MFShutdown(); 
     } 

     CoUninitialize(); 
    } 
} 

HRESULT ProcessConverter(){ 

    HRESULT hr; 
    IMFSourceReader* pReader = NULL; 

    // Change the URL 
    if(FAILED(hr = MFCreateSourceReaderFromURL(L"Wildlife.wmv", NULL, &pReader))){ 
     return hr; 
    } 

    DWORD dwMediaTypeIndex = 0; 
    IMFMediaType* pType = NULL; 

    hr = pReader->GetNativeMediaType((DWORD)MF_SOURCE_READER_FIRST_VIDEO_STREAM, dwMediaTypeIndex, &pType); 

    if(SUCCEEDED(hr)){ 

     // We must ask for a subtype compatible with DMO : 
     // ARGB32 RGB24 RGB32 RGB555 RGB565 AYUV IYUV UYVY Y211 Y411 Y41P YUY2 YUYV YV12 YVYU 
     hr = pType->SetGUID(MF_MT_SUBTYPE, MFVideoFormat_YV12); 

     if(SUCCEEDED(hr)){ 
      hr = pReader->SetCurrentMediaType((DWORD)MF_SOURCE_READER_FIRST_VIDEO_STREAM, NULL, pType); 
     } 

     // We need this because we use the MediaType to initialize the Transform 
     if(SUCCEEDED(hr)){ 
      SAFE_RELEASE(pType); 
      hr = pReader->GetCurrentMediaType((DWORD)MF_SOURCE_READER_FIRST_VIDEO_STREAM, &pType); 
     } 

     if(SUCCEEDED(hr)){ 

      IMFTransform* pTransform = NULL; 
      hr = InitDMO(&pTransform, pType); 

      if(SUCCEEDED(hr)){ 

       hr = ProcessSample(pReader, pTransform); 

       // Seems not really needed with the DMO 
       /*hr = */ pTransform->ProcessMessage(MFT_MESSAGE_COMMAND_FLUSH, NULL); 
       /*hr = */ pTransform->ProcessMessage(MFT_MESSAGE_NOTIFY_END_OF_STREAM, NULL); 
       /*hr = */ pTransform->ProcessMessage(MFT_MESSAGE_NOTIFY_END_STREAMING, NULL); 
      } 

      SAFE_RELEASE(pTransform); 
     } 
    } 

    SAFE_RELEASE(pType); 
    SAFE_RELEASE(pReader); 

    return hr; 
} 

HRESULT InitDMO(IMFTransform** ppTransform, IMFMediaType* pType){ 

    HRESULT hr = CoCreateInstance(CLSID_CFrameRateConvertDmo, NULL, CLSCTX_INPROC_SERVER, IID_IMFTransform, reinterpret_cast<void**>(ppTransform)); 

    if(SUCCEEDED(hr)){ 
     hr = (*ppTransform)->SetInputType(0, pType, 0); 
    } 

    if(SUCCEEDED(hr)){ 
     // Change the frame rate as needed, here num = 60000 and den = 1001 
     hr = MFSetAttributeRatio(pType, MF_MT_FRAME_RATE, 60000, 1001); 
    } 

    if(SUCCEEDED(hr)){ 
     hr = (*ppTransform)->SetOutputType(0, pType, 0); 
    } 

    if(SUCCEEDED(hr)){ 
     hr = (*ppTransform)->ProcessMessage(MFT_MESSAGE_NOTIFY_BEGIN_STREAMING, NULL); 
    } 

    if(SUCCEEDED(hr)){ 
     hr = (*ppTransform)->ProcessMessage(MFT_MESSAGE_NOTIFY_START_OF_STREAM, NULL); 
    } 

    return hr; 
} 

HRESULT ProcessSample(IMFSourceReader* pReader, IMFTransform* pTransform){ 

    HRESULT hr; 
    IMFMediaType* pType = NULL; 

    if(FAILED(hr = pTransform->GetOutputCurrentType(0, &pType))){ 
     return hr; 
    } 

    // We need the frame size to create the sample buffer. 
    UINT32 uiFrameSize = 0; 
    hr = pType->GetUINT32(MF_MT_SAMPLE_SIZE, &uiFrameSize); 

    SAFE_RELEASE(pType); 

    if(FAILED(hr) || uiFrameSize == 0){ 
     return hr; 
    } 

    BOOL bProcess = TRUE; 
    DWORD streamIndex; 
    DWORD flags; 
    LONGLONG llTimeStamp; 
    IMFSample* pSample = NULL; 
    DWORD dwReaderCount = 0; 
    DWORD dwDMOCount = 0; 

    while(bProcess){ 

     hr = pReader->ReadSample((DWORD)MF_SOURCE_READER_FIRST_VIDEO_STREAM, 0, &streamIndex, &flags, &llTimeStamp, &pSample); 

     if(FAILED(hr) || flags != 0){ 
      bProcess = FALSE; 
     } 
     else{ 

      hr = ProcessDMO(pTransform, pSample, dwDMOCount, uiFrameSize); 

      // You can check timestamp from the SourceReader 
      //hr = pSample->GetSampleDuration(&llTimeStamp); 
      //hr = pSample->GetSampleTime(&llTimeStamp); 

      SAFE_RELEASE(pSample); 
      dwReaderCount++; 
     } 
    } 

    // Todo : check dwReaderCount and dwDMOCount here. 
    // For example with native frame rate = 30000/1001 and dwReaderCount = 900 
    // DMO frame rate = 30000/1001 -> dwReaderCount = 900 
    // DMO frame rate = 60000/1001 -> dwReaderCount = 1800 
    // DMO frame rate = 25/1 -> dwReaderCount = 750 

    SAFE_RELEASE(pSample); 

    return hr; 
} 

HRESULT ProcessDMO(IMFTransform* pTransform, IMFSample* pSample, DWORD& dwDMOCount, const UINT32 uiFrameSize){ 

    HRESULT hr = S_OK; 

    MFT_OUTPUT_DATA_BUFFER outputDataBuffer; 
    DWORD processOutputStatus = 0; 

    // Todo : we should avoid recreating the buffer... 
    hr = InitOutputDataBuffer(pTransform, &outputDataBuffer, uiFrameSize); 

    while(hr == S_OK){ 

     hr = pTransform->ProcessOutput(0, 1, &outputDataBuffer, &processOutputStatus); 

     if(hr == MF_E_TRANSFORM_NEED_MORE_INPUT){ 
      break; 
     } 

     // You can check new timestamp from the DMO 
     /*if(outputDataBuffer.pSample != NULL){ 

      LONGLONG llTimeStamp = 0; 
      hr = outputDataBuffer.pSample->GetSampleTime(&llTimeStamp); 
      hr = outputDataBuffer.pSample->GetSampleDuration(&llTimeStamp); 
     }*/ 

     dwDMOCount++; 
    } 

    if(hr == MF_E_TRANSFORM_NEED_MORE_INPUT){ 
     hr = pTransform->ProcessInput(0, pSample, 0); 
    } 

    if(outputDataBuffer.pSample != NULL){ 
     SAFE_RELEASE(outputDataBuffer.pSample); 
    } 

    return hr; 
} 

HRESULT InitOutputDataBuffer(IMFTransform* pMFTransform, MFT_OUTPUT_DATA_BUFFER* pOutputBuffer, const UINT32 uiFrameSize){ 

    MFT_OUTPUT_STREAM_INFO outputStreamInfo; 
    DWORD outputStreamId = 0; 

    ZeroMemory(&outputStreamInfo, sizeof(outputStreamInfo)); 
    ZeroMemory(pOutputBuffer, sizeof(*pOutputBuffer)); 

    HRESULT hr = pMFTransform->GetOutputStreamInfo(outputStreamId, &outputStreamInfo); 

    if(SUCCEEDED(hr)){ 

     if((outputStreamInfo.dwFlags & MFT_OUTPUT_STREAM_PROVIDES_SAMPLES) == 0 && 
      (outputStreamInfo.dwFlags & MFT_OUTPUT_STREAM_CAN_PROVIDE_SAMPLES) == 0){ 

      IMFSample* pOutputSample = NULL; 
      IMFMediaBuffer* pMediaBuffer = NULL; 

      hr = MFCreateSample(&pOutputSample); 

      if(SUCCEEDED(hr)){ 
       hr = MFCreateMemoryBuffer(uiFrameSize, &pMediaBuffer); 
      } 

      if(SUCCEEDED(hr)){ 
       hr = pOutputSample->AddBuffer(pMediaBuffer); 
      } 

      if(SUCCEEDED(hr)){ 
       pOutputBuffer->pSample = pOutputSample; 
       pOutputBuffer->pSample->AddRef(); 
      } 

      SAFE_RELEASE(pMediaBuffer); 
      SAFE_RELEASE(pOutputSample); 
     } 
    } 

    return hr; 
}

來源

2015-12-02 16:01:48 mofo77

如何在MF應用程序中使用幀速率轉換器DMO

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