convert all MP4 files to MOV with ffmpeg and grunt

gruntfile.js

/**
 * This is just a little helper I made when I had to convert a lot of MP4 files. 
 * Using ffmpeg this works fine but it just needed to be automated. Maybe this isn't the best 
 * solution, it's quick and dirty but I was happy with its results.
 * The grunt script ran overnight to process about a hundred video files.
 */
 
module.exports = function(grunt) {
  var _ = require('underscore');

  grunt.registerTask('default', convertVideoFiles);

  function convertVideoFiles(){
    var done = this.async();

    var mp4s = grunt.file.expand({ filter: 'isFile'}, ['**/*.MP4']);

    function mp4ToMov(path){
      convert(path, function(){
        if (_.isEmpty(mp4s)){
          done();
        } else {
          mp4ToMov(mp4s.shift());
        }
      });
    }

    mp4ToMov(mp4s.shift());
  }

  function convert(path, callback){

    if (!grunt.file.exists(path)){
      console.log(path + ' not found');
      callback();
    }

    var ext = '.' + _.last(path.split('.'));
    var mov = path.replace(ext, '.MOV');

    grunt.util.spawn({
      cmd: "ffmpeg",
      args: ['-i', path, mov]
    }, function(err, result, code){
      if (err){
        console.log('ERROR: ' + path);
        callback();
      }

      grunt.file.delete(path);
      console.log('converted ' + mov);

      callback();

    });
  }

};

package.json

{
  "name": "mp4-mov-convert",
  "version": "0.1.0",
  "description": "mp4 to mov conversion helper for ffmpeg",
  "author": "Manuel Lehner",
  "license": "MIT",
  "devDependencies": {
    "grunt": "^0.4.5",
    "underscore": "^1.8.3"
  }
}