Make FLAC encoder bit depth depend on input sample format, add sampleFormat audio transformation option, fix incorrect bitrate validation for FLAC (closes #357)

test/browser/flac-encoder-extension.test.ts

@@ -0,0 +1,107 @@
+import { expect, test } from 'vitest';
+import { Input } from '../../src/input.js';
+import { ALL_FORMATS } from '../../src/input-format.js';
+import { AudioSampleSource } from '../../src/media-source.js';
+import { AudioSampleSink } from '../../src/media-sink.js';
+import { assert } from '../../src/misc.js';
+import { Output } from '../../src/output.js';
+import { FlacOutputFormat } from '../../src/output-format.js';
+import { AudioSample } from '../../src/sample.js';
+import { BufferSource } from '../../src/source.js';
+import { BufferTarget } from '../../src/target.js';
+import { registerFlacEncoder } from '@mediabunny/flac-encoder';
+
+test('FLAC encoder, 24-bit', async () => {
+	registerFlacEncoder();
+
+	const sampleRate = 48000;
+	const channels = 2;
+	const durationSeconds = 2;
+	const data = createF32SineWave(sampleRate, channels, durationSeconds);
+
+	using sample = await encodeAndDecodeFirstSample(new AudioSample({
+		data,
+		format: 'f32',
+		numberOfChannels: channels,
+		sampleRate,
+		timestamp: 0,
+	}));
+
+	expect(sample.format).toBe('s32');
+});
+
+test('FLAC encoder, 16-bit', async () => {
+	registerFlacEncoder();
+
+	const sampleRate = 48000;
+	const channels = 2;
+	const durationSeconds = 2;
+	const data = createS16SineWave(sampleRate, channels, durationSeconds);
+
+	using sample = await encodeAndDecodeFirstSample(new AudioSample({
+		data,
+		format: 's16',
+		numberOfChannels: channels,
+		sampleRate,
+		timestamp: 0,
+	}));
+
+	expect(sample.format).toBe('s16');
+});
+
+const createF32SineWave = (sampleRate: number, channels: number, durationSeconds: number) => {
+	const totalFrames = sampleRate * durationSeconds;
+	const data = new Float32Array(totalFrames * channels);
+
+	for (let i = 0; i < totalFrames; i++) {
+		const value = Math.sin(2 * Math.PI * 440 * i / sampleRate);
+		for (let ch = 0; ch < channels; ch++) {
+			data[i * channels + ch] = value;
+		}
+	}
+
+	return data;
+};
+
+const createS16SineWave = (sampleRate: number, channels: number, durationSeconds: number) => {
+	const totalFrames = sampleRate * durationSeconds;
+	const data = new Int16Array(totalFrames * channels);
+
+	for (let i = 0; i < totalFrames; i++) {
+		const value = Math.round(Math.sin(2 * Math.PI * 440 * i / sampleRate) * 32767);
+		for (let ch = 0; ch < channels; ch++) {
+			data[i * channels + ch] = value;
+		}
+	}
+
+	return data;
+};
+
+const encodeAndDecodeFirstSample = async (audioSample: AudioSample) => {
+	const output = new Output({
+		format: new FlacOutputFormat(),
+		target: new BufferTarget(),
+	});
+
+	const audioSource = new AudioSampleSource({ codec: 'flac' });
+	output.addAudioTrack(audioSource);
+
+	await output.start();
+	await audioSource.add(audioSample);
+	audioSource.close();
+	await output.finalize();
+
+	using input = new Input({
+		source: new BufferSource(output.target.buffer!),
+		formats: ALL_FORMATS,
+	});
+
+	const track = await input.getPrimaryAudioTrack();
+	assert(track);
+
+	const sink = new AudioSampleSink(track);
+	const sample = await sink.getSample(0);
+	assert(sample);
+
+	return sample;
+};

test/node/flac-encoder-extension.test.ts

@@ -47,7 +47,7 @@ test('FLAC encoding', async () => {
 		target: new BufferTarget(),
 	});
 
-	const audioSource = new AudioSampleSource({ codec: 'flac', bitrate: 1 });
+	const audioSource = new AudioSampleSource({ codec: 'flac' });
 	output.addAudioTrack(audioSource);
 
 	await output.start();
@@ -97,7 +97,7 @@ test('FLAC with huge timestamps', async () => {
 		target: new BufferTarget(),
 	});
 
-	const audioSource = new AudioSampleSource({ codec: 'flac', bitrate: 1 });
+	const audioSource = new AudioSampleSource({ codec: 'flac' });
 	output.addAudioTrack(audioSource);
 
 	await output.start();