如果输入视频有多个音轨，你需要再添加一个，然后使用以下命令:

ffmpeg -i input_video_with_audio.avi -i new_audio.ac3 -map 0 -map 1 -codec copy output_video.avi

-map 0表示从第一个输入文件(input_video_with_audio.avi)复制(包括)所有流，-map 1表示从第二个输入文件(new_audio.ac3)复制(包括)所有流(在本例中是一个流)。

没有什么对我很有效(我想这是因为我输入的。mp4视频没有任何音频)，所以我发现这对我很有效:

Ffmpeg -i input_video.mp4 -i balipraavid .wav -map 0:v:0 -map 1:a:0 output.mp4

取代音频

ffmpeg -i video.mp4 -i audio.wav -map 0:v -map 1:a -c:v copy -shortest output.mp4

The -map option allows you to manually select streams / tracks. See FFmpeg Wiki: Map for more info. This example uses -c:v copy to stream copy (mux) the video. No re-encoding of the video occurs. Quality is preserved and the process is fast. If your input audio format is compatible with the output format then change -c:v copy to -c copy to stream copy both the video and audio. If you want to re-encode video and audio then remove -c:v copy / -c copy. The -shortest option will make the output the same duration as the shortest input.

添加音频

ffmpeg -i video.mkv -i audio.mp3 -map 0 -map 1:a -c:v copy -shortest output.mkv

The -map option allows you to manually select streams / tracks. See FFmpeg Wiki: Map for more info. This example uses -c:v copy to stream copy (mux) the video. No re-encoding of the video occurs. Quality is preserved and the process is fast. If your input audio format is compatible with the output format then change -c:v copy to -c copy to stream copy both the video and audio. If you want to re-encode video and audio then remove -c:v copy / -c copy. The -shortest option will make the output the same duration as the shortest input.

混合/组合两个音频输入为一个

使用video.mkv中的视频。混合音频和视频。MKV和音频。M4a使用合并滤波器:

ffmpeg -i video.mkv -i audio.m4a -filter_complex "[0:a][1:a]amerge=inputs=2[a]" -map 0:v -map "[a]" -c:v copy -ac 2 -shortest output.mkv

更多信息请参见FFmpeg Wiki:音频通道。

生成无声音频

你可以使用anullsrc过滤器来制作一个无声的音频流。过滤器允许您选择所需的频道布局(单声道，立体声，5.1等)和采样率。

ffmpeg -i video.mp4 -f lavfi -i anullsrc=channel_layout=stereo:sample_rate=44100 \
-c:v copy -shortest output.mp4

也看到

将两个音频流合并为一个 FFmpeg Wiki:音频通道操作 FFmpeg mux视频和音频从另一个视频

这展示了如何用ffmpeg将所有音轨合并到一个完整的目录:

ffmpeg -i video.mp4 -i audio.mp3 -map 0:v -map 1:a -c:v copy -shortest output.mp4

Mp3音乐wav

ffmpeg -i music.mp3 music.wav

截断适合视频

ffmpeg -i music.wav -ss 0 -t 37 musicshort.wav

音乐和视频混合

ffmpeg -i musicshort.wav -i movie.avi final_video.avi

如果你正在使用旧版本的FFMPEG，你不能升级，你可以做以下:

ffmpeg -i PATH/VIDEO_FILE_NAME.mp4 -i PATH/AUDIO_FILE_NAME.mp3 -vcodec copy -shortest DESTINATION_PATH/NEW_VIDEO_FILE_NAME.mp4

注意，我使用了-vcodec