How to use B-frames?
Galaxoid-333 opened this issue · comments
In this article I read about the use of B frames:
https://codecalamity.com/amd-re-introduces-the-b-frame/
But when I use these B frame settings there is no effect. I use CQP/VBR/CBR, 264 and 265 codecs. Version VCEEnc 7.00.
Can you tell me how to use B frames?
I cannot have bframes enabled on RX5500XT.
Bframes is not supported on this device, disabled.
Therefore, I think we need RX6xxx series for H.264 bframes, as the articles uses RX6900.
Correct, only latest RDNA2 has re-enabled B-frames, sorry I wasn't clearer in the article about which versions support it. AMD doesn't prove a nice list like Nvidia does with their support Matrix for NVENC, so I honestly don't know which do or don't have it.
Have to manually check with VCEEncC64.exe --check-features and see if it lists Bframe support: yes
If it does support it just need to add --bframes 3 (and I also recommend --b-pyramid) to your encoding command.
One oddity is that if --bframes is specified when the codec is HEVC, VCEEnc will warn that it isn't supported (6900XT, this is apparently correct), but doesn't complain about --b-pyramid.
B-frame support check is for --bframes only, --b-pyramid is just ignored.
I'll close this issue as the topic has been answered.