On Tue, Jan 29, 2019 at 23:04:23 +0100, Zoltan Kerenyi Nagy wrote: > Slight modification does not work either: > > ffmpeg -f lavfi -i nullsrc -f alsa -i hw:0,0 -filter_complex > "[0:a]showwaves=s=1280x720:mode=line:colors=Blue[v]" -map "[v]" -map 0:a > -c:v libx264 -r 15 http://localhost:5554/video.ffm > > error: > > Stream specifier ':a' in filtergraph description > [0:a]showwaves=s=1280x720:mode=line:colors=Blue[v] matches no streams.
This is why you should always show us the *complete* uncut console output. You are hiding interesting info otherwise. Your first input (0) is nullsrc, a video source. So "[0:a]" does not specify a valid stream. You are not even using nullsrc, so you should probably omit "-f lavfi -i nullsrc", then the rest should work. Moritz _______________________________________________ ffmpeg-user mailing list [email protected] http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email [email protected] with subject "unsubscribe".
