It looks like if you are to use voxl-streamer to encode a RAW8 pipe, it will default to encoding it in h264. Is there a way to change this to 265? I tried recompiling the service and editing the pipeline.c file to use the 265 encoder where applicable (and changed other mentions of 264 to 265) but the stream fails when I try to start it. Is there a simpler way to achieve what I'm trying to do that I'm missing?

@ bendraper , unfortunately we have not tried using voxl-streamer for encoding h265. voxl-camera-server does support h265 encoding and by the way we recently fixed the CBR functionality : https://docs.modalai.com/voxl-camera-server/#constant-quantization-vs-constant-bitrate-mode Do you need to encode an image that you modify outside of the camera server? If you are willing to share the changes you made while trying to get it to work, i can test it and see if I can spot anything that's easy to fix (you could provide a patch or link to a fork). If we can get it to work, it could be a nice extension of voxl-streamer. Alex

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streamer default h265

Unsolved VOXL SDK and Software

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A Alex Kushleyev

@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
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@Alex-Kushleyev Thanks for letting me know! I'll have to give it a try
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