Decoding H.264 through CUDA GPU

Hi I am using cudaDecodeD3D9 project in samples to see the decoding through GPU and as per the doc cudaPostProcessFrame(CUdeviceptr *ppDecodedFrame, size_t nDecodedPitch,
CUdeviceptr *ppTextureData, size_t nTexturePitch,
CUmodule cuModNV12toARGB,
CUfunction fpCudaKernel, CUstream streamID) method first Argument have decoded data and I try to dump the decoded data in ppDecodedFrame to a file and and file is empty.

Is the decoded data is in a different place please let me know. why this pointer does not have the decoded data since decoding is happening perfectly.