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PK · Guest

Hi All,

Not sure if this is the correct place to post. But any help on the issue
would be appreciated.
I wanted to get the audio stream from the given mp3, wma or a wav file. So I
followed the code sample as follows. I have a multithreaded application. I
found that there was handle count increase whenever I called
AddMediaStream() / OpenFile() of the interface IAMMultiMediaStream. The
handle count was increasing in a very drastic manner and not by just 1.

Some of the links I refered was
http://dpi.ufv.br/downloads/C++IntroductoryEdition/VCB600ENU1/MSDN_VCB/SAMPLES/VC98/SDK/GRAPHICS/DIRECTANIMATION/HELP/DS/DSSD0375.HTM

The code snippet for the calling function is as follows

hr = RenderFileToMMStream(ptszFileName, &pMMStream);

if(SUCCEEDED(hr)&& pMMStream)

{

hr = RenderStreamForFileInfo(pMMStream);

pMMStream->Release();

}

HRESULT RenderStreamForFileInfo(IMultiMediaStream *pMMStream)

{

HRESULT hr = S_OK;

WAVEFORMATEX wfx;

#define DATA_SIZE 4096

PBYTE pBuffer = (PBYTE)LocalAlloc(LMEM_FIXED, DATA_SIZE);

IMediaStream *pStream = NULL;

IAudioStreamSample *pSample = NULL;

IAudioMediaStream *pAudioStream = NULL;

IAudioData *pAudioData = NULL;

pMMStream->GetMediaStream(MSPID_PrimaryAudio, &pStream);

pStream->QueryInterface(IID_IAudioMediaStream, (void **)&pAudioStream);

assert(pAudioStream != NULL);

pAudioStream->GetFormat(&wfx);

AudioFormat audio_format;

audio_format.bits_per_sample = wfx.wBitsPerSample;

audio_format.channels = wfx.nChannels;

audio_format.sample_rate = wfx.nSamplesPerSec;

if ((audio_format.sample_rate < 0) || (audio_format.sample_rate == 0))

{

hr = E_FAIL;

goto DONE;

}

hr = CoCreateInstance(CLSID_AMAudioData, NULL, CLSCTX_INPROC_SERVER,
IID_IAudioData, (void **)&pAudioData);

assert(pAudioData != NULL);

hr = pAudioData->SetBuffer(DATA_SIZE, pBuffer, 0);

hr = pAudioData->SetFormat(&wfx);

hr = pAudioStream->CreateSample(pAudioData, 0, &pSample);

DWORD dwLength;

pAudioData->GetInfo(NULL, NULL, &dwLength);

DONE:

SAFE_RELEASE( pAudioData );

SAFE_RELEASE( pSample );

SAFE_RELEASE( pStream );

SAFE_RELEASE( pAudioStream );

LocalFree((HLOCAL)pBuffer);

return hr;

}

HRESULT RenderFileToMMStream(const TCHAR* ptszFileName, IMultiMediaStream
**ppMMStream)

{

IAMMultiMediaStream *pAMStream = NULL;

HRESULT hr = S_OK;

CP2P_LICMGR objLicMgr;

//CComPtr<IMediaStream> poMediaStream;

hr = CoCreateInstance(CLSID_AMMultiMediaStream, NULL, CLSCTX_INPROC_SERVER,
IID_IAMMultiMediaStream, (void **)&pAMStream);

if(SUCCEEDED(hr)&& pAMStream)

{

pAMStream->Initialize(STREAMTYPE_READ, AMMSF_NOGRAPHTHREAD, NULL);

pAMStream->AddMediaStream(NULL, &MSPID_PrimaryAudio, 0,
NULL );//&poMediaStream);

#ifndef UNICODE

WCHAR* pwszFileName = NULL;

hr = objLicMgr.ConvertStrToUnicode( ptszFileName, &pwszFileName );

pAMStream->OpenFile(pwszFileName, AMMSF_RUN);

SAFE_ARRAYDELETE( pwszFileName );

#else

pAMStream->OpenFile(ptszFileName, AMMSF_RUN);

#endif

*ppMMStream = pAMStream;

//pAMStream->AddRef();

//poMediaStream->Release();

}

return hr;

}

Note: In RenderFileToMMStream() function I had come accross one article
which said when we make a call to AddMediaStream() the last parameter will
contain the IMediaStream pointer. We should call the Release on this
pointer. But Release() is a private member of this interface.
Also note that this functions are called several times on a multithreaded
environment.

Let me know if there any issue in the code. Am I missing any Release() on
any interface or something like that. Any inputs regarding the same would be
greatly appreciated :-)

Regds,
PK

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