Getting duration

Sample code

The following sample code shows how to get the duration from a MPEG file. This sample shows the duration of the MPEG file and ends.

#include <stdio.h>

#include <dshow.h>

// change here
#define	FILENAME L"c:\\DXSDK\\Samples\\Media\\butterfly.mpg"

int
main()
{
 IGraphBuilder *pGraphBuilder;
 IMediaControl *pMediaControl;
 IMediaPosition *pMediaPosition;

 REFTIME length;

 CoInitialize(NULL);

 CoCreateInstance(CLSID_FilterGraph,
	NULL,
	CLSCTX_INPROC,
	IID_IGraphBuilder,
	(LPVOID *)&pGraphBuilder);

 pGraphBuilder->QueryInterface(IID_IMediaControl,
	(LPVOID *)&pMediaControl);

 pGraphBuilder->QueryInterface(IID_IMediaPosition,
	(LPVOID *)&pMediaPosition);

 pMediaControl->RenderFile(FILENAME);

 pMediaPosition->get_Duration(&length);
 printf("%lf\n", length);

 pMediaPosition->Release();
 pMediaControl->Release();
 pGraphBuilder->Release();

 CoUninitialize();

 return 0;
}

The IMediaPosition::get_Duration method returns REFTIME. REFTIME shows the duration of the media content in seconds. REFTIME is defined as following, and is a double value.

typedef double REFTIME;