Understanding MFXVideoDECODE_DecodeHeader

Understanding MFXVideoDECODE_DecodeHeader

Hi

I am callingMFXVideoDECODE_DecodeHeader in an attempt to initialize the mfxVideoParam structure. The source of the H.264 encoded data is in the following file (http://software.intel.com/file/m/42421) which was generated using the Intel Media SDK (version 1.3). The sequence and picture parameter sets are contained in the first 46 bytes of the file.

If I provide the first 50 or 75 bytes fromthis file to the MFXVideoDECODE_DecodeHeader function (via the mfxBitStream parameter), the function returns MFX_ERR_NONE and the mfxVideoParam structure is filled out correctly. If I provide a different number of bytes (e.g. 46, 47, 48, 49, 70, 71, 72, 73, 74), the function returns MFX_ERR_MORE_DATA.

I expected to be able to provide only the first 46 bytes. Can anyone explain to me why this does not work?

Thanks, Steve

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Hi Steve,

I was able to reproduce the issue you reported. Looking at the implementation of DecodeHeader it seems we likely have a bug here.

Thanks for sharing your finding and helping us improve Intel Media SDK. We hope to provide a solution for this in both SW and HW implementation as soon as possible.

In the meantime you should be able to workaround the issue padding the data provided to DecodeHeader.

Regards,Petter

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