merge multiple video files and stream by fluent-ffmpeg in nodejs

Question

I am trying to merge multiple video files into stream output using fluent-ffmpeg. But it only streams the first video.

res.set('content-type', 'video/webm');    
var proc = ffmpeg()
        .mergeAdd('file-1.webm') // tried with input()
        .mergeAdd('file-2.webm')
        .mergeAdd('file-3.webm')
        .format('webm')
        .size('680x?')
        .on('end', function() {
          console.log('file has been converted succesfully');
        })
        .on('error', function(err) {
          console.log('an error happened: ' + err.message);
        })
        // save to stream
        .pipe(res, {end:true})

Any ideas?

Answer 1

Yes, though I have this done without fluent-ffmpeg. Instead, spawning ffmpeg and using an input file that lists the files to merge in the correct order.

import { spawn } from 'child_process';

The input file should look like:

file 'path/to/webm1.webm'
file 'path/to/webm2.webm'
file 'path/to/webm3.webm'

Then call ffmpeg

await spawn('ffmpeg', [
'-y',
'-safe', '0',
'-f', 'concat',
'-i', 'path/to/ffmpeg-input.txt'),
'-c', 'copy',
'path/to/finalvideo.webm')
]);