Hello to everyone who read this!  I met an unpleasant problem. I bought a new router to have such ability to install OpenWRT and run ffmpeg to capture RTSP stream from my chinese IP-camera to USB HDD attached to my router. This camera can give H264 or MJPEG stream.  Now I've installed OpenWRT and ffmpeg, ran the command  ffmpeg -i "rtsp://user:password@192.168.1.103:554/unicast" -r 30 -vcodec copy -acodec copy -t 30 "/mnt/usb/NVR/1.mkv"  and got these errors:  with using MJPEG  Could not find co...