ffmpeg -f v4l2 -video_size 640x480 -framerate 30 -vcodec mjpeg -i /dev/video0 -video_size 640x480 -framerate 30 -vcodec mjpeg -i /dev/video1 -framerate 30 -filter_complex hstack -r 30 -threads 0 -c:v libx264 -preset veryfast outputsplit.ts