Unusally high bitrate when encoding through vah265enc using RX 7900 XT
Describe your issue
I used vah265enc plugin to record video through obs and obs-vaapi plugin and noticed the bitrate will increase to several hundred Mbps when leaving the bitrate setting to 0 (auto-calculate the bitrate), and the encoder got overloaded and skipped a lot of frames. But I found the video encoded through vaapih265enc plugin was fine, and the encoding finishes as soon as the recording stops. I have also tried limiting the bitrate to 60Mbps, but the encoder still got overloaded. Could there be a regression?
Expected Behavior
The encoding finishes as soon as recording stops, and the encoder does not got overloaded.
Observed Behavior
The encoder got overloaded and skipped a lot of frames when a video is played or a game is active.
Setup
- Operating System: Arch Linux
- Device: Computer
- GPU: RX 7900 XT
- Driver: Mesa 23.0.0
- GStreamer Version: 1.22.0
- Record Resolution: 3840x2160@60fps
- obs-vaapi link: obs-vaapi
Steps to reproduce the bug
- Install OBS
- Install obs-vaapi plugin through pacman or aur on Arch Linux
- Open OBS
- Go to Settings
- Navigate to Output tab
- Change output mode from Simple to Advanced in Recordings Tab
- Change encoder to VAAPI H.265 (not the legacy one)
- Encode a video using the default settings.
How reproducible is the bug?
The reproducibility of the bug is always once after during the steps above.
Screenshots if relevant
Solutions you have tried
Limit the bit rate to 60Mbps, changed to variable bit rate, decrease max-qp from 51 to 40 and qpi,qpp, qpb to 20