Hi @Rowan-Dempster , you are right, actually, there is no option right now to log from an ion buffer using voxl-logger. However, voxl-replay has an option to send camera frames as ion buffers. I have not tested it recently, but you could give it a try : https://gitlab.com/voxl-public/voxl-sdk/utilities/voxl-logger/-/blob/extend-cam-logging/tools/voxl-replay.cpp
For offline processing, it should not matter much whether you are using ion buffers or not. There would be a bit more cpu usage, but hopefully not too much. Having voxl-replay support cam playback as ion buffers is probably more important than using ion buffers for logging, since then your offline processing pipeline uses the same flow (ion buffers) as the live vio pipeline.
We may add logging from ion buffer, but it's probably not a high priority.
By the way, i wanted to mention one detail. I recently made a change in camera server dev branch to allocate the ion buffers that are used for incoming raw images as uncached buffers. This actually happens to reduce the cpu usage (so that cpu does not have to check / flush cache before sending the buffer to the GPU). The cpu reduction was something like 5% of one core per camera (for a large 4K image). For majority of hires camera use cases, this is beneficial, because usually the cpu never touches the raw10 image before sending to GPU.
However, when you are logging the raw10 image to disk using voxl-logger, the cpu will have to read the contents of the whole image and send it via the pipe - uncached reads are more expensive. There will be increased cpu usage (i dont remember how much), but it should still be fine unless you are trying to log very large images at high rate. If you wanted to profile the cpu usage while logging, you can just disable making the raw buffers uncached and see if that helps. I have not yet figured out a clean way to handle this, maybe i will add a param for type of caching to use for the raw camera buffer.
look for the following comment in https://gitlab.com/voxl-public/voxl-sdk/services/voxl-camera-server/-/blob/dev/src/hal3_camera_mgr.cpp :
//make raw preview stream uncached for Bayer cameras to avoid cpu overhead mapping mipi data to cpu, since it will go to gpu directly
Alex
