I can see this code, it looks like related to the header of stream.
I believe if you set mfxEncParams.mfx.FrameInfo.PicStruct to MFX_PICSTRUCT_PROGRESSIVE, you will set this flag to 1.
Not quite understand your question, you want general_progressive_source_flag set to 1, in our code it is defined as general.progressive_source_flag, I was saying if you set the field PicStructure to MFX_PICSTURE_PROGRESSIVE in the input video parameter structure, you set general.progressive_source_flag to true or "yes" whatever you expected.
If you have an issue, could you let me know how to reproduce it?
Mark i tryed both types
mfxEncParams.mfx.FrameInfo.PicStruct = MFX_PICSTRUCT_PROGRESSIVE;
and _mfxEncParams.mfx.ExtendedPicStruct = MFX_PICSTRUCT_PROGRESSIVE;
I don't know what to try now, simple this parameters don't enable general_progressive_source_flag = 1, the first parameter enable high tier to 1