On Sat, Jan 19, 2019 at 14:55:55 -0700, JD wrote: > I have a video that was sped up and now the voice is like > that of cats in cartoons. > How can I at least lower the pitch back to normal? > Since the whole video was sped up, I would rather > slow down the whole video (video and audio) AND lower > the pitch back to near normal?
There's a wiki page covering this: https://trac.ffmpeg.org/wiki/How%20to%20speed%20up%20/%20slow%20down%20a%20video (There's a part saying "Using a complex filtergraph, you can speed up video and audio at the same time:". IMO, you can also do this with separate "simple" filters, using "-vf" and "-af".) Carl Eugen failed to mention that the setpts filter doesn't change the audio speed. The audio example in the wiki, using "atempo", changes the speed while _maintaining_ the pitch. To stretch the audio _including_ pitch change, you need to instead change the sample speed with the "asetrate" filter, and re-adapt the output sample rate (because your output file will require a sane sample rate such as 44.1k or 48k) with "-ar". E.g. to reduce the speed of the audio to 0.8x of the given input, assuming an input sample rate of 48000k: $ ffmpeg -i input -af asetrate=38400 -ar 48000 output (38400 is 0.8 * 48000. I wish asetrate would understand an "input sample rate" variable.) 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".
