mediabunny/test/browser/custom-sample-resources.test.ts

import { expect, test } from 'vitest';
import {
	VideoSampleResource,
	VideoSampleColorSpace,
	VideoSample,
	AudioSampleResource,
	AudioSample,
} from '../../src/sample.js';
import { toUint8Array } from '../../src/misc.js';

class ImageVideoSampleResource extends VideoSampleResource {
	constructor(public image: HTMLImageElement | null) {
		super();
	}

	getFormat(): VideoPixelFormat {
		return 'RGBA';
	}

	getCodedWidth() {
		return this.image!.width;
	}

	getCodedHeight() {
		return this.image!.height;
	}

	getColorSpace() {
		return new VideoSampleColorSpace({
			matrix: 'rgb',
			primaries: 'bt709',
			transfer: 'iec61966-2-1',
			fullRange: true,
		});
	}

	allocationSize() {
		return this.image!.width * this.image!.height * 4;
	}

	copyTo(destination: AllowSharedBufferSource): PlaneLayout[] {
		const canvas = new OffscreenCanvas(this.image!.width, this.image!.height);
		const ctx = canvas.getContext('2d')!;

		ctx.drawImage(this.image!, 0, 0);

		const imageData = ctx.getImageData(0, 0, this.image!.width, this.image!.height);
		toUint8Array(destination).set(imageData.data);

		return [{
			offset: 0,
			stride: this.image!.width * 4,
		}];
	}

	close() {
		this.image = null;
	}
}

test('Custom VideoSample resource usage', async () => {
	const image = new Image();
	image.src = '/red-image.png';
	await image.decode();

	const resource = new ImageVideoSampleResource(image);
	const sample = new VideoSample(resource, { timestamp: 0 });
	expect(sample.format).toBe('RGBA');
	expect(sample.codedWidth).toBe(2048);
	expect(sample.codedHeight).toBe(2048);
	expect(sample.colorSpace).toEqual({
		matrix: 'rgb',
		primaries: 'bt709',
		transfer: 'iec61966-2-1',
		fullRange: true,
	});

	const videoFrame = sample.toVideoFrame();
	const canvas = new OffscreenCanvas(1024, 1024);
	const context = canvas.getContext('2d')!;
	context.drawImage(videoFrame, 0, 0);
	const imageData = context.getImageData(0, 0, 1024, 1024);
	expect([...imageData.data.slice(0, 4)]).toEqual([255, 0, 0, 255]);

	videoFrame.close();

	const clone = sample.clone();
	sample.close();
	expect(resource.image).not.toBe(null);

	clone.close();
	expect(resource.image).toBe(null);
});

test('Custom VideoSample resource, invalid construction', async () => {
	const image = new Image();
	image.src = '/red-image.png';
	await image.decode();

	const resource = new ImageVideoSampleResource(image);
	// @ts-expect-error Wrong
	expect(() => new VideoSample(resource)).toThrow(TypeError);
	// @ts-expect-error Wrong
	expect(() => new VideoSample(resource, { duration: 0 })).toThrow(TypeError);
});

class AudioBufferAudioSampleResource extends AudioSampleResource {
	constructor(
		public audioBuffer: AudioBuffer | null,
		public timestamp: number,
	) {
		super();
	}

	getFormat(): AudioSampleFormat {
		return 'f32-planar';
	}

	getSampleRate() {
		return this.audioBuffer!.sampleRate;
	}

	getNumberOfFrames() {
		return this.audioBuffer!.length;
	}

	getNumberOfChannels() {
		return this.audioBuffer!.numberOfChannels;
	}

	getTimestamp() {
		return this.timestamp;
	}

	allocationSize() {
		const frameCount = this.audioBuffer!.length;
		return frameCount * Float32Array.BYTES_PER_ELEMENT;
	}

	copyTo(destination: AllowSharedBufferSource, options: AudioDataCopyToOptions): void {
		const frameCount = this.audioBuffer!.length;
		const planeIndex = options.planeIndex;

		const channel = this.audioBuffer!.getChannelData(planeIndex);

		let destView: Float32Array;
		if (destination instanceof ArrayBuffer) {
			destView = new Float32Array(destination);
		} else if (destination instanceof SharedArrayBuffer) {
			destView = new Float32Array(destination);
		} else {
			destView = new Float32Array(destination.buffer, destination.byteOffset, destination.byteLength / 4);
		}

		const frameOffset = options.frameOffset ?? 0;
		const copyFrameCount = options.frameCount !== undefined ? options.frameCount : (frameCount - frameOffset);

		for (let i = 0; i < copyFrameCount; i++) {
			destView[i] = channel[i + frameOffset]!;
		}
	}

	close() {
		this.audioBuffer = null;
	}
}

test('Custom AudioSample resource usage', async () => {
	const audioContext = new AudioContext();
	const audioBuffer = audioContext.createBuffer(2, 48000, 48000);

	const leftChannel = audioBuffer.getChannelData(0);
	const rightChannel = audioBuffer.getChannelData(1);
	for (let i = 0; i < 48000; i++) {
		const t = i / 48000;
		leftChannel[i] = Math.sin(2 * Math.PI * 440 * t);
		rightChannel[i] = Math.cos(2 * Math.PI * 440 * t);
	}

	const resource = new AudioBufferAudioSampleResource(audioBuffer, 0);
	const sample = new AudioSample(resource);

	expect(sample.format).toBe('f32-planar');
	expect(sample.sampleRate).toBe(48000);
	expect(sample.numberOfFrames).toBe(48000);
	expect(sample.numberOfChannels).toBe(2);
	expect(sample.timestamp).toBe(0);
	expect(sample.duration).toBeCloseTo(1);

	const buffer = new ArrayBuffer(48000 * 4);
	sample.copyTo(buffer, { planeIndex: 0 });

	const view = new Float32Array(buffer);
	expect(view[0]).toBeCloseTo(0, 4);
	expect(view[13]).toBeCloseTo(Math.sin(2 * Math.PI * 440 * (13 / 48000)));

	const clone = sample.clone();
	sample.close();
	expect(resource.audioBuffer).not.toBe(null);

	clone.close();
	expect(resource.audioBuffer).toBe(null);
});