FFmpeg has a number of video generating filters, listed in the documentation as "video sources":
- cellauto
- color
- mptestsrc
- fei0r_src
- life
- nullsrc, rgbtestsrc, testsrc
Those are great for using with other filters like overlay, but is there any way that I can generate a movie consisting of just one of those video sources without any input video?
Something like:
ffmpeg -vf color=red" red_movie.mp4
Except that that errors out with At least one input file must be specified.