Split youtube audio/video file into sections using definition file

split.vid.js

// tested on https://www.youtube.com/watch?v=5nhp6ULk7mE
// see http://www.regexr.com/3bp42
exec = function (cmd) { return require("child_process").execSync(cmd, {stdio:[null, null, null]}).toString() }
console.log((function() {
	fs = require("fs")
	youtubeVideoFilename = process.argv[2]
	specsFilename = process.argv[3]
	length = exec(`ffprobe -show_format "${youtubeVideoFilename}"`).split("duration=")[1].split("\n")[0]
	end = new Date(length * 1000).toISOString().substr(11, 8);
	songSpecifications = fs.readFileSync(specsFilename)
		.toString()
		.split("\n")
		.map(function(line) {
			descPart = line.match(/((?:\d:)?\d\d?:\d\d) (.*)/)
			return [descPart[1], descPart[2]]
		})

		for(var i = 0; i < songSpecifications.length; i++) {
			fromTime = songSpecifications[i][0]
			filename = songSpecifications[i][1]
			if ((i + 1) === songSpecifications.length) {
				toTime = end;
			} else {
				toTime = songSpecifications[i + 1][0]
			}

			shellLine = `ffmpeg -y -i "${youtubeVideoFilename}" -ss ${fromTime} -to ${toTime} -acodec libmp3lame -ab 192k "${filename}.mp3"`
			console.log(`Executing: ${shellLine}`);
			exec(shellLine);
		}
})())