Pietro pietrop

Converting mkv to mp4 with `ffmpeg`

Essentially just copy the existing video and audio stream as is into a new container, no funny business!

The easiest way to "convert" MKV to MP4, is to copy the existing video and audio streams and place them into a new container. This avoids any encoding task and hence no quality will be lost, it is also a fairly quick process and requires very little CPU power. The main factor is disk read/write speed.

With ffmpeg this can be achieved with -c copy. Older examples may use -vcodec copy -acodec copy which does the same thing.

These examples assume ffmpeg is in your PATH. If not just substitute with the full path to your ffmpeg binary.

Single file conversion example

Pluck Unique Values from Array of Javascript Objects

Implementation

const pluck = key => array => Array.from(new Set(array.map(obj => obj[key])));

	function onOpen() {
	var ui = DocumentApp.getUi();
	ui.createMenu('Convert to .RST')
	.addItem('Convert to .RST and email me the result', 'ConvertToRestructuredText')
	.addToUi();
	}

	// Adopted from https://github.com/mangini/gdocs2md by Renato Mangini
	// License: Apache License Version 2.0
	String.prototype.repeat = String.prototype.repeat \|\| function(num) {

	'use strict';

	function parseTime(s) {
	let t = 0;
	const p = s.split(':');
	let ss = p.pop().replace(',', '.');
	t += parseFloat(ss);
	ss = parseInt( p.pop() \|\| '0', 10);
	t += ss * 60;
	ss = parseInt( p.pop() \|\| '0', 10);

	if ('NodeList' in window && !NodeList.prototype.forEach) {
	console.info('polyfill for IE11');
	NodeList.prototype.forEach = function (callback, thisArg) {
	thisArg = thisArg \|\| window;
	for (var i = 0; i < this.length; i++) {
	callback.call(thisArg, this[i], i, this);
	}
	};
	}