mediabunny/test/node/matroska-muxer.test.ts

import { expect, test } from 'vitest';
import path from 'node:path';
import { Input } from '../../src/input.js';
import { BufferSource, FilePathSource } from '../../src/source.js';
import { ADTS, ALL_FORMATS } from '../../src/input-format.js';
import { EncodedPacketSink } from '../../src/media-sink.js';
import { Output } from '../../src/output.js';
import { BufferTarget } from '../../src/target.js';
import { MkvOutputFormat } from '../../src/output-format.js';
import { Conversion } from '../../src/conversion.js';
import { assert } from '../../src/misc.js';
import { EncodedVideoPacketSource } from '../../src/media-source.js';
import { EncodedPacket } from '../../src/packet.js';

const __dirname = new URL('.', import.meta.url).pathname;

test('Matroska muxer internally converts ADTS to AAC', async () => {
	using input = new Input({
		source: new FilePathSource(path.join(__dirname, '../public/sample3.aac')),
		formats: ALL_FORMATS,
	});

	expect(await input.getFormat()).toBe(ADTS);

	const inputTrack = await input.getPrimaryAudioTrack();
	assert(inputTrack);

	const inputDecoderConfig = await inputTrack.getDecoderConfig();
	expect(inputDecoderConfig!.description).toBeUndefined(); // ADTS input has no description

	const output = new Output({
		format: new MkvOutputFormat(),
		target: new BufferTarget(),
	});

	const conversion = await Conversion.init({ input, output, showWarnings: false });
	await conversion.execute();

	using outputAsInput = new Input({
		source: new BufferSource(output.target.buffer!),
		formats: ALL_FORMATS,
	});

	const outputTrack = await outputAsInput.getPrimaryAudioTrack();
	assert(outputTrack);

	expect(await outputTrack.getCodec()).toBe('aac');
	expect(await outputTrack.getSampleRate()).toBe(await inputTrack.getSampleRate());
	expect(await outputTrack.getNumberOfChannels()).toBe(await inputTrack.getNumberOfChannels());

	const outputDecoderConfig = await outputTrack.getDecoderConfig();
	expect(outputDecoderConfig!.description).toBeDefined();

	const outputSink = new EncodedPacketSink(outputTrack);

	let count = 0;
	for await (const packet of outputSink.packets()) {
		// Packets should NOT be ADTS frames (should not start with 0xFFF sync word)
		const isAdts = packet.data[0] === 0xff && (packet.data[1]! & 0xf0) === 0xf0;
		expect(isAdts).toBe(false);
		count++;
	}

	expect(count).toBe(4557);
});

test('Negative start timestamps', async () => {
	await testNegativeTimestampRoundTrip(
		Array.from({ length: 50 }, (_, index) => (index - 10) / 10),
		0.1,
		10,
	);
});

test('Wholly negative timestamps', async () => {
	await testNegativeTimestampRoundTrip([-1, -0.9, -0.8, -0.7, -0.6], 0.1, 10);
});

const testNegativeTimestampRoundTrip = async (timestamps: number[], duration: number, frameRate: number) => {
	const output = new Output({
		format: new MkvOutputFormat(),
		target: new BufferTarget(),
	});

	const source = new EncodedVideoPacketSource('vp8');
	output.addVideoTrack(source, { frameRate });

	await output.start();

	const meta = { decoderConfig: { codec: 'vp8', codedWidth: 1280, codedHeight: 720 } };
	const inputPackets = timestamps.map((timestamp, index) => new EncodedPacket(
		new Uint8Array(1024).fill(index),
		'key',
		timestamp,
		duration,
	));

	for (let i = 0; i < inputPackets.length; i++) {
		await source.add(inputPackets[i]!, i === 0 ? meta : undefined);
	}

	await output.finalize();

	using input = new Input({
		source: new BufferSource(output.target.buffer!),
		formats: ALL_FORMATS,
	});

	const track = await input.getPrimaryVideoTrack();
	assert(track);
	const sink = new EncodedPacketSink(track);

	const outputPackets: EncodedPacket[] = [];
	for await (const packet of sink.packets()) {
		outputPackets.push(packet);
	}

	expect(outputPackets.map(packet => ({
		timestamp: packet.timestamp,
		duration: packet.duration,
	}))).toEqual(inputPackets.map(packet => ({
		timestamp: packet.timestamp,
		duration: packet.duration,
	})));

	for (const inputPacket of inputPackets) {
		const outputPacket = await sink.getPacket(inputPacket.timestamp);
		assert(outputPacket);

		expect({
			timestamp: outputPacket.timestamp,
			duration: outputPacket.duration,
		}).toEqual({
			timestamp: inputPacket.timestamp,
			duration: inputPacket.duration,
		});
	}
};