Enumerating MPEG2 Format Compatible Compressors Example for C++

// the following code demonstrates enumerates the valid audio 
 and video compressors for the 

// MPEG2 target format. A recommended compressor is also retrieved.

void EnumMPEG2Compressors(IltmmConvert *pConvert)

{

   IltmmCompressors *pCompressors;

   IltmmCompressor *pCompressor;

   IltmmTargetFormats *pTargetformats;

   IltmmTargetFormat* pTargetformat;

   long lCount, lIndex, lValid;

   BSTR Name;



   // set the target format to MPEG2

   pConvert->put_TargetFormat(ltmmCapture_TargetFormat_MPEG2_PROGRAM);



   pConvert->get_TargetFormats(&pTargetformats);

   pTargetformats->Item(ltmmCapture_TargetFormat_MPEG2_PROGRAM, 
 &pTargetformat);

   pTargetformats->Release();



   // Audio 

   // get the compressors collection

   pConvert->get_AudioCompressors(&Compressors);

   pCompressors->get_Count(&lCount);



   for(lIndex = 0; lIndex < lCount; lIndex++)

   {

      long lValid;

      pCompressors->Item(lIndex, 
 &pCompressor);

      pCompressor->get_Name(&Name);

      pTargetformat->IsValidCompressor(Name, 
 &valid);

      if( lValid != ltmmTargetFormat_Compressor_Invalid 
 )

      {

         // do whatever needed 
 with the valid compressor (i.e. add it to some list)

      }

      ::SysFreeString(Name);

      pCompressor->Release();

   }



   // get the recommended compressor for the current format

   pTargetformat->get_RecommendedAudioCompressor(&Name);

   if( Name )

   {

      // do whatever needed with the recommended 
 compressor (i.e. select it)

   }



   pCompressors->Release();



   // Video 

   // get the compressors collection

   pConvert->get_VideoCompressors(&Compressors);

   pCompressors->get_Count(&lCount);



   for(lIndex = 0; lIndex < lCount; lIndex++)

   {

      long lValid;

      pCompressors->Item(lIndex, 
 &pCompressor);

      pCompressor->get_Name(&Name);

      pTargetformat->IsValidCompressor(Name, 
 &valid);

      if( lValid != ltmmTargetFormat_Compressor_Invalid 
 )

      {

         // do whatever needed 
 with the valid compressor (i.e. add it to some list)

      }

      ::SysFreeString(Name);

      pCompressor->Release();

   }



   // get the recommended compressor for the current format

   pTargetformat->get_RecommendedVideoCompressor(&Name);

   if( Name )

   {

      // do whatever needed with the recommended 
 compressor (i.e. select it)

   }



   pCompressors->Release();



   pTargetformat->Release();

}