CUDA Video Decoder crash Simple decoder application crash

I’m trying to knock up a version of the cudaDecodeGL sample application but on a live source, rendering in OpenGL. I’ve got a really simple first step application which is crashing on a call to cuvidCreateDecoder. First I create the CUDA context:

g_oDevice = cutGetMaxGflopsDeviceId();

cutilGLDeviceInitDrv ( g_oDevice, argcp, argv );

cutilDrvSafeCallNoSync( cuGLCtxCreate( &g_oContext, CU_CTX_BLOCKING_SYNC, g_oDevice ));

// Create the Video Context Lock (used for synchronization)

cutilDrvSafeCallNoSync( cuvidCtxLockCreate ( &cuCtxLock, g_oContext ));

This block works for my live encoder project. Then very simply I try to create a decoder context:

memset ( (void*)&decodeParams, 0, sizeof ( CUVIDDECODECREATEINFO ));

decodeParams.CodecType = cudaVideoCodec_H264;

decodeParams.ulWidth = GL_IMAGE_WIDTH;

decodeParams.ulHeight = GL_IMAGE_HEIGHT;

decodeParams.ulNumDecodeSurfaces = 20; // MAX_FRM_CNT;

	

// Limit decode memory to 24MB (16M pixels at 4:2:0 = 24M bytes)

while ( decodeParams.ulNumDecodeSurfaces * decodeParams.ulWidth * decodeParams.ulHeight > 16*1024*1024 )

{

  decodeParams.ulNumDecodeSurfaces--;

}

decodeParams.ChromaFormat = cudaVideoChromaFormat_420;

decodeParams.OutputFormat = cudaVideoSurfaceFormat_NV12;

decodeParams.DeinterlaceMode = cudaVideoDeinterlaceMode_Adaptive;

// Output format

decodeParams.ulTargetWidth = GL_IMAGE_WIDTH;

decodeParams.ulTargetHeight = GL_IMAGE_HEIGHT;

decodeParams.ulNumOutputSurfaces = 2;

decodeParams.ulCreationFlags = cudaVideoCreate_Default;

decodeParams.vidLock = cuCtxLock;

CUresult result = cuvidCreateDecoder( pDecoder, &decodeParams );

So all basically hard coded results, look good in the debugger. I never get a return from creating the decoder, and there is no stack trace (it dies somewhere in nvcuvid.dll).

I have the latest CUDA 3.2, my encoder project works and the cudaDecodeGL project seems to run correctly. Is there maybe a missing step between creating the context and the decoder?

Thanks!

This was a stupid error on my part. Calls to cuvidCreateDecoder expect that the decoder object already has memory assigned to it, my decleration was:

CUvideodecoder *oDecoder_;

It just needed to be a member variable, that or allocated before the call

CUvideodecoder pDecoder;