Gamma differences between RGB and H.264 streams

I’m using NvFBC to capture a remote screen and compress it with H.264, and decoding the stream with the Capture SDK and displaying with OpenGL on the receiving end. If I switch between capturing raw RGB pixels and H.264, I find that the RGB image is what I expect and the H.264 requires gamma correction. Is there a implicit gamma adjustment happening in the H.264 encoder or decoder that would account for the difference? If so, can we control this or disable it?

Maybe you hit “limited color space” problem http://kodi.wiki/view/Video_levels_and_color_space.
The problem is usually at receiver end - try another h264 pipeline/player.

That’s interesting. I’m pretty sure what I’m seeing is a gamma difference, though. If I apply a gamma correction to the decoded H.264 stream, I can get back a pretty good representation of what I was capturing.

Maybe compression generic quatization and/or color conversion lost. Try to encode in 4:4:4.
Check https://forums.adobe.com/thread/1063696 or https://forums.adobe.com/thread/1103186 or other Google hits.
Check/set parameters in “NV_ENC_CONFIG_H264_VUI_PARAMETERS” .

Thats all from me.