markdown ffmpeg.md

Posted 2021-05-05

# [merge file](https://blessing.studio/use-ffmpeg-to-concat-flv-videos-downloaded-by-bilibili-client/)
`ffmpeg.exe -f concat -safe 0 -i "clips.txt" -c copy "video.mp4"`

# [reverse](https://blog.csdn.net/Contex_A17/article/details/82014826)
* 视频倒放，无音频
`ffmpeg.exe -i inputfile.mp4 -filter_complex [0:v]reverse[v] -map [v] -preset superfast reversed.mp4`
* 视频倒放，音频不变
`ffmpeg.exe -i inputfile.mp4 -vf reverse reversed.mp4`
* 音频倒放，视频不变
`ffmpeg.exe -i inputfile.mp4 -map 0 -c:v copy -af "areverse" reversed_audio.mp4`
* 音视频同时倒放
`ffmpeg.exe -i inputfile.mp4 -vf reverse -af areverse -preset superfast reversed.mp4`