Cut multiple parts from a video and merge them tog

Question

I am trying to cut specific parts out from a video and then merge all those parts into a single video file using nodejs and ffmpeg.

Here's my code and currently I can cut only one part out of the video from .setStartTime to .setDuration and that part is being saved.

var ffmpeg = require('fluent-ffmpeg');

var command = ffmpeg()
  .input('./videos/placeholder-video.mp4')
  .setStartTime('00:00:03')
  .setDuration('02')
  .output('./videos/test.mp4')

  .on('start', function(commandLine) {
    console.log('Started: ' + commandLine);
  })

  .on('end', function(err) {   
    if(!err)
    {
      console.log('conversion Done');
    }                 
  })

  .on('error', function(err){
    console.log('error: ', +err);
  }).run();

How do I cut out multiple parts out from the video and merge them in a single video file. I know about .mergeToFile method but how do I use it after cutting different parts from my video.

I tried using .setStartTime and .setDuration twice like below but the first one's are being ignored.

.input('./videos/placeholder-video.mp4')
.setStartTime('00:00:03')
.setDuration('02')
.setStartTime('00:00:15')
.setDuration('05')
.output('./videos/test.mp4')

Answer 1

PLEASE READ UPDATE

Could not test it yet, but try following: Set the input video two times, like this:

.input('./videos/placeholder-video.mp4')
.setStartTime('00:00:03')
.setDuration('02')
.input('./videos/placeholder-video.mp4')
.setStartTime('00:00:15')
.setDuration('05')

Then you can merge the multiple inputs with .mergeToFile.

---

UPDATE

My answer cannot work due to restriction of .setDuration. It is an output option, so it defines how long transcoding to the output file is done: https://github.com/fluent-ffmpeg/node-fluent-ffmpeg It is not used to define the length/duration of the input.

Another option would be .loop, but apparently it is not supported for this purpose: https://video.stackexchange.com/questions/12905/repeat-loop-input-video-with-ffmpeg/12906#12906

If you really want to use nodejs, you need multiple commands

• cut the input video to temporary files, one for each cut
• merge the temporary files to one output file

Something like this:

var command1 = ffmpeg()
  .input('./small.mp4')
  .seekInput('00:00:02')
  .withDuration(1)
  .output('./temp1.mp4')
  .run();

var command2 = ffmpeg()
  .input('./small.mp4')
  .seekInput('00:00:01')
  .withDuration(3)
  .output('./temp2.mp4')
  .run();

var command2 = ffmpeg()
  .input('./temp1.mp4')
  .input('./temp2.mp4')
  .mergeToFile('./merge.mp4', './temp');

Big problem: your nodejs script will not start if temporary files are not present. So it would be much more easier to use a bash or batch script.