fluent-ffmpeg：如何在 node.js 中将立体声 mp3 拆分为 2 个单声道文件？

Question

I'm trying to convert an mp3 file stereo to 2 mp3 mono node's fluent-ffmpeg module. This is example for terminal:

ffmpeg -i stereo.wav -map_channel 0.0.0 left.wav -map_channel 0.0.1 right.wav

I need the implementation of this functionality in fluent-ffmpeg .

Answer 1

not sure about the mono, but if you want to split a file, you can use

ffmpeg(local_dir).outputOptions('-f segment')
        .outputOptions(`-segment_time ${length of each mp3 }`).save(`${save_dir}out%03d.mp3`)

hope it can help you

Answer 2

It's been a long time since you've asked it, but maybe it can help to others.

The way I found to solve the same problem was opening the file twice and save each channel separated.

const splitChannels = (file, leftChannelName, rightChannelName) =>{

    ffmpeg(file)
        .outputOption('-map_channel 0.0.0')
        .save(leftChannelName)
        .on('error', (err) => {
            console.log(`An error occurred: ${err.message}`);
        })
        .on('end', () => {
            console.log('Left channel splitted!');
        })

    ffmpeg(pathToAudio)
        .outputOption('-map_channel 0.0.1')
        .save(rightChannelName)
        .on('error', (err) => {
            console.log(`An error occurred: ${err.message}`);
        })
        .on('end', () => {
            console.log('Right channel splitted!');
        })
}

splitChannels('./files/test.wav', 'left.wav', 'right.wav');

More info: https://trac.ffmpeg.org/wiki/AudioChannelManipulation

Of course you can use .wav or .mp3 too.

Hope it helps!