Intel QuickSync H264 decoder (qsvh264dec) rank?

Hi all,
I have a question about qsvh264dec ranked as “marginal” ; as stated somewhere in the documentation, I take this low rank “as a warning”.

I was wondering if someone (@seungha ? :slight_smile: ) has anything more specific than a general warning, like some known issues or limitations.
To extend on my thoughts, I’ve seen this QuickSync decoder wildly outperform the d3d11h264dec on some devices (Windows 11 / Intel i7 with Iris Xe), so I’m really wondering if I should definitely switch to QuickSync.

Thanks for your insights !

Wondering how much outperforms, and your pipeline. One thing I know is that d3d11h264dec output cannot be used by pixel shader, so vendor implemented ID3D11VideoProcessor (it’s blackbox) is required for color conversion/resizing. Or need to copy to another texture so that decoder output can be used by shader. qsv decoders does not have such limitation.

One reason I didn’t bump the qsv decoder rank is that I didn’t observe significant performance differences between qsv and d3d11, and we prefer our bitstream parser / picture management done by our decoder baseclass over vendor implemented one.