On Wed, 28 Apr 2021 09:03:26 +0200, Michael Koch <astroelectro...@t-online.de> wrote:
>Am 28.04.2021 um 08:51 schrieb Bo Berglund: >> Sometimes when I download a video it turns out to have some issues that has >> raised the audio pitch of the video making it not so enjoyable to watch/hear. >> So I wonder if there is an ffmpeg command that can modify the pitch of the >> audio >> without changing the playback speed or lipsync? > >Yes, this is possible with a combination of asetrate, atempo and >aresample filters. >See chapter 3.4 in my book: >http://www.astro-electronic.de/FFmpeg_Book.pdf > Thanks for the book! It has many useful items. But chapter 3.4 seems to deal only in modifying an audio file whereas I am talking about an mp4 video with both audio and video content. I had tested this (which I found by googling) before I posted: ffmpeg -i input20.mp4 -filter:a "atempo=1.25" -vn output20.mp4 There were no errors displayed but the resulting file *ONLY* contains the audio part, I neeed both and the audio change must not change the length or lipsync of the file. I already have a script to change lipsync using ffmpeg this way (shifting audio 350 ms here): ffmpeg -hide_banner -i input.mp4 -itsoffset -0.35 -i input.mp4 -map 1:v -map 0:a -c copy output.mp4 Is this basically what one has to do, specifying the input twice? I am not really understanding how all the ffmpeg arguments do work... -- Bo Berglund Developer in Sweden _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
