Extending video editor functionality

VideoEditor.js

//
//  VideoEditor.js
//
//  Created by Josh Bavari on 01-14-2014
//  Modified by Ross Martin on 01-29-15
//

var exec = require('cordova/exec'),
    pluginName = 'VideoEditor';

function VideoEditor() {}

VideoEditor.prototype.transcodeVideo = function (successCallback, fail, options) {
    // https://github.com/apache/cordova-plugin-file-transfer/blob/master/www/FileTransfer.js#L197
    var self = this,
        win = function (result) {
            if (typeof result.lengthComputable !== "undefined") {
                if (self.onprogress) {
                    self.onprogress(result);
                }
            } else {
                successCallback(result);
            }
        };
    exec(win, fail, pluginName, 'transcodeVideo', [options]);
};

VideoEditor.prototype.createThumbnail = function (success, error, options) {
    exec(success, error, pluginName, 'createThumbnail', [options]);
};

VideoEditor.prototype.killVideoProcessor = function (success, error, options) {
    exec(success, error, pluginName, 'killVideoProcessor', [options]);
};

module.exports = new VideoEditor();