ffmpeg.exe -i "movie.mp4" -itsoffset 0.3 -i "movie.mp4" -itsoffset 0.4 -i "movie.mp4" -map 0:v -map 1:a:0 -map 2:a:1 -c copy "movie-audio-delayed.mp4"

これで一つ目の音声を0.3秒遅らせて、2つ目の音声を0.4秒遅らせる処理になる。
詳しくはStackoverflowの回答を参考に。

参考

http://stackoverflow.com/questions/9643348/delay-audio-with-ffmpeg

Tetsu @ironsand

思いついたアイデアをすぐに形にできる能力を身につけたいのでRailsを頑張って習得中。仕事ください。

http://programming.ironsand.net/

Why not register and get more from Qiita?

We will deliver articles that match you
By following users and tags, you can catch up information on technical fields that you are interested in as a whole
you can read useful information later efficiently
By "stocking" the articles you like, you can search right away

What you can do with signing up