Extracted Audio not in Sync with Video
Hi all, My use case is that I want to extract audio from a mp4, edit the audio, and then put the audio and the video back together. It works fine, but over the course of the two hour video, the audio gets out of sync with the video and falls behind it (visibly, so you can see the mouth and sound aren't in sync). I extract the audio with a command like this: ffmpeg -y -i "v1-ed.mp4" -vn "a1.wav" I edit a1.wav with audacity to create a1-ed.wav. And then combine audio and video with a command like this: ffmpeg -y -i "v1-ed.mp4" -i "a1-ed.wav" -filter_complex "[1]anull[aud]; [0]fade=t=out:st=6673.87:n=24[out]" -strict experimental -shortest -map [out] -map [aud] "lecture.mp4" Is there any easy way to make sure the audio stays sync'd through this process? Thanks, Josh
ffmpeg -y -i "v1-ed.mp4" -i "a1-ed.wav" -filter_complex "[1]anull[aud]; [0]fade=t=out:st=6673.87:n=24[out]" -strict experimental -shortest -map 0:v:0 -map 1:a:0 "lecture.mp4" 你试试使用这个命令，看看能否解决你的问题。 You can try using this command to see if it can solve your problem. The translation in English is: "Try canceling the fade-in and fade-out effect you added." china kaidi ------------------ Original ------------------ From: "FFmpeg user questions" <jnfo-d@grauman.com>; Date: Tue, Oct 31, 2023 07:31 AM To: "ffmpeg-user"<ffmpeg-user@ffmpeg.org>; Subject: [FFmpeg-user] Extracted Audio not in Sync with Video Hi all, My use case is that I want to extract audio from a mp4, edit the audio, and then put the audio and the video back together. It works fine, but over the course of the two hour video, the audio gets out of sync with the video and falls behind it (visibly, so you can see the mouth and sound aren't in sync). I extract the audio with a command like this: ffmpeg -y -i "v1-ed.mp4" -vn "a1.wav" I edit a1.wav with audacity to create a1-ed.wav. And then combine audio and video with a command like this: ffmpeg -y -i "v1-ed.mp4" -i "a1-ed.wav" -filter_complex "[1]anull[aud]; [0]fade=t=out:st=6673.87:n=24[out]" -strict experimental -shortest -map [out] -map [aud] "lecture.mp4" Is there any easy way to make sure the audio stays sync'd through this process? Thanks, Josh _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-request@ffmpeg.org with subject "unsubscribe".
I tried this and it doesn't help. The audio and video are still not in sync, even when you don't use the fade-out... Josh On Tue, 31 Oct 2023, 凯迪软件（咨询、售后） via ffmpeg-user wrote:
ffmpeg -y -i "v1-ed.mp4" -i "a1-ed.wav" -filter_complex "[1]anull[aud]; [0]fade=t=out:st=6673.87:n=24[out]" -strict experimental -shortest -map 0:v:0 -map 1:a:0 "lecture.mp4"
?????????????????????????????????????????? You can try using this command to see if it can solve your problem.
The translation in English is: "Try canceling the fade-in and fade-out effect you added."
china kaidi
------------------ Original ------------------ From: "FFmpeg user questions" <jnfo-d@grauman.com>; Date: Tue, Oct 31, 2023 07:31 AM To: "ffmpeg-user"<ffmpeg-user@ffmpeg.org>;
Subject: [FFmpeg-user] Extracted Audio not in Sync with Video
Hi all,
My use case is that I want to extract audio from a mp4, edit the audio, and then put the audio and the video back together. It works fine, but over the course of the two hour video, the audio gets out of sync with the video and falls behind it (visibly, so you can see the mouth and sound aren't in sync).
I extract the audio with a command like this: ffmpeg -y -i "v1-ed.mp4" -vn "a1.wav"
I edit a1.wav with audacity to create a1-ed.wav.
And then combine audio and video with a command like this: ffmpeg -y -i "v1-ed.mp4" -i "a1-ed.wav" -filter_complex "[1]anull[aud]; [0]fade=t=out:st=6673.87:n=24[out]" -strict experimental -shortest -map [out] -map [aud] "lecture.mp4"
Is there any easy way to make sure the audio stays sync'd through this process?
Thanks,
Josh _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user
To unsubscribe, visit link above, or email ffmpeg-user-request@ffmpeg.org with subject "unsubscribe". _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user
To unsubscribe, visit link above, or email ffmpeg-user-request@ffmpeg.org with subject "unsubscribe".
participants (3)
-
Josh -
Joshua Grauman
-
凯迪软件（咨询、售后）