The mfxExtCodingOptionSPSPPS structure is inadequate for getting the video parameter set sequence header for HEVC. If you use this method with MFXVideoENCODE_GetVideoParam you can retrieve the SPS (00 00 01 42) and PPS (00 00 01 44) sequence header information.
But HEVC introduced a more important parameter set: video parameter set (00 00 01 40). Right now, the only way to get that is to do a dummy encoding of one frame.
It would be much more efficient to be able to extract all 3 sequence header buffers using a structure like mfxExtCodingOptionSPSPPS.
