@bendraper, in case you need to set lower CBR bitrates than previously stated, we have a workaround for the 1.5 and 3.0 mbps limits. Camera server in dev branch supports lower bitrates and we have tested h265 as low as 0.25Mbps works pretty well.
The workaround tells the encoder that fps is higher than actual, allowing us to achieve effective lowering of the bitrate. You can just set your bitrate in camera server config to the desired bitrate and if bitrate is below the “limit”, the encoder fps setting is adjusted accordingly to achieve the low bitrate. This does not have any adverse effect on output quality and the fps value is not actually sent with the encoded stream.
If you want to adjust the bitrate dynamically below that “limit”, you may want to hardcode the value of m_fpsHackScale to a certain value like 12. Value of 12 would allow you to set h265 to 3.0/12 = 0.25Mbps or higher.
https://gitlab.com/voxl-public/voxl-sdk/services/voxl-camera-server/-/blob/dev/src/omx_video_encoder.cpp
Let me know if you need any more details. We will work towards improving this workaround in the future.
Alex