Sajan

Oh, I understand. Camera, hardware video decoder and hardware video encoder - they all appear now as /dev/videoX devices, because new hardware videocodec accelerator driver (or standalone video decoder and video encoder drivers) became V4L2 kind of driver. Also thanks for the reference link.

Ok, maybe, I have not enough or outdated information. Could you help me to understand latest changes and correct me? 1. I think, camera driver and codec video engine driver - are different things, because there are completely different hardware: CSI video input and videocodec accelerator. 2. I think, video engine driver and video coding software with special codecs - are different things, because a driver does not encode/decode video, it only gives access to videocodec accelerator. And video coding software (app or lib) is not a driver, but uses a driver to get access to the videocodec accelerator. 3. So is it really driver performs video decoding in bootlin? Also, as I understand, bootlin - is not just a driver, but big project with it's own Linux, alternative to Armbian, with builtin specific driver and libs. Can I install bootlin driver on Armbian? 4. Doesn't previously mentioned https://github.com/uboborov/sunxi-cedar-mainline use /dev/cedar_dev path? Is it outdated? 5. About encoding on H3. FFmpeg-Cedrus (https://github.com/agustinov/FFmpeg-Cedrus) maybe is outdated, because uses /dev/cedar_dev, but seems to encode without lots of artifacts.

/dev/video0 - usually is the camera V4L driver. Cedrus (sunxi video engine) driver usually is /dev/cedar_dev. Also you can see

https://github.com/twdragon/FFmpeg/tree/cedrus264 may produce green line artefact at the frame bottom on 1080p resolution. In the https://github.com/agustinov/FFmpeg-Cedrus/tree/4.4-cedrus this artefact is fixed.