podcast-visualizer/generate-demuxer.ts

import findLoudness, { SwapPoint } from "./find-loudness";

const graph_density = 8000;

const threshold_at_point = 2;

const inertia_s = 0.3;
const inertia_samples = inertia_s * graph_density;

const s = (n: number) => n / graph_density;

const minutes = (units: number) => Math.floor(s(units) / 60);

const hours = (units: number) => Math.floor(units / graph_density / 60 / 60);

const formatTime = (units: number) =>
	`${hours(units)}:${minutes(units)}:${Math.floor(s(units) % 60)}`;

type Mode = { left: boolean; right: boolean };

async function run() {
	const [left_breaks, right_breaks] = await Promise.all([
		findLoudness(
			"/tmp/leftraw",
			threshold_at_point,
			inertia_samples,
			"left"
		),
		findLoudness(
			"/tmp/rightraw",
			threshold_at_point,
			inertia_samples,
			"right"
		),
	]);

	const merged = [...left_breaks, ...right_breaks].sort((a, b) =>
		a.position_start < b.position_start
			? -1
			: a.position_start > b.position_start
				? 1
				: 0
	);

	// console.log("left breaks:", left_breaks);
	// console.log(`right_breaks`, right_breaks);
	// console.log(`merged`, merged);

	function new_mode(m: Mode, s: SwapPoint): Mode {
		return { ...m, [s.label]: s.loud };
	}

	function mode_to_string(mode: Mode) {
		if (mode.left && mode.right) {
			return "both";
		}
		for (const side of ["left", "right"]) {
			if (mode[side as keyof Mode]) {
				return side;
			}
		}
		return "none";
	}

	console.log("file", `${process.cwd()}/pics/none.png`);
	let last_point = 0;
	let mode: Mode = { left: false, right: false };
	let last_file;
	let total = 0;
	for (let i = 2; i < merged.length; i++) {
		const point = merged[i];
		mode = new_mode(mode, point);
		const file = `${process.cwd()}/pics/${mode_to_string(mode)}.png`;
		const duration = (point.position_start - last_point) / graph_density;
		console.log(
			"duration",
			(point.position_start - last_point) / graph_density
		);
		console.log("file", file);
		last_point = point.position_start;
		last_file = file;
		total += duration * graph_density;
	}
	console.log("duration", merged[merged.length - 1].duration / graph_density);
	console.log("file", last_file);
	console.error(total, formatTime(total));
}
run();