We are developing AI vision app on Orange Pi 4 and Intel Movidius Neural Stick 2. Everything is working great up to FullHD with software decoders. But now we need to decode 4K video stream from RTSP to feed it to OpenCV/OpenVINO.
We could successfully use Kwiboo's ffmpeg with current Armbian 5.8.6 kernel without patches. Decoder is definitely working and we can see 120 fps with `ffmpeg -hwaccel drm -hwaccel_output_format drm_prime -i big1.avi -benchmark -f null -` (big1.avi is 3840 x 2160 h264 video).
However I can't find a way to scale it using RGA. As far as I understand it should be some kind of mem2mem filter but I'm not sure how to do it. The best I could come so far is the command: `ffmpeg -y -hwaccel drm -hwaccel_output_format drm_prime -i big1.avi -an -vf 'hwdownload,format=nv12,scale=1280:-2' -pix_fmt rgb24 -f rawvideo /dev/null` that gives about 15fps and 20% CPU usage.
So my question is how can I scale and convert to RGB888 without 4K decoded frame downloaded to the CPU?
paintenzero got a reaction from gounthar in Mainline VPU