Add @mediabunny/ac3 extension package

packages/mp3-encoder/README.md

@@ -102,8 +102,6 @@ The WASM build itself is a performance-optimized, SIMD-enabled build of LAME 3.1
 
 ## Building and development
 
-Building this library is done using the build commands in the [Mediabunny root](https://github.com/Vanilagy/mediabunny).
-
 For simplicity, all built WASM artifacts are included in the repo, since these rarely change. However, here are the instructions for building them from scratch:
 
 ### Prerequisites
@@ -148,7 +146,7 @@ emcc src/lame-bridge.c build/libmp3lame.a \
     -o build/lame.js
 ```
 
-This generates `build/lame.js`, which contains both the JavaScript "glue code" as well as the compiled WASM encoded with Base64.
+This generates `build/lame.js`, which contains both the JavaScript "glue code" as well as the compiled WASM inlined.
 
 ### Building the package
 

packages/mp3-encoder/src/encode.worker.ts

@@ -146,7 +146,10 @@ const onMessage = (data: { id: number; command: WorkerCommand }) => {
 						command.data.sampleRate,
 						command.data.bitrate,
 					);
-					result = { success: true };
+					result = {
+						type: command.type,
+						success: true,
+					};
 				}; break;
 
 				case 'encode': {
@@ -154,13 +157,19 @@ const onMessage = (data: { id: number; command: WorkerCommand }) => {
 						command.data.audioData,
 						command.data.numberOfFrames,
 					);
-					result = { encodedData };
+					result = {
+						type: command.type,
+						encodedData,
+					};
 					transferables.push(encodedData);
 				}; break;
 
 				case 'flush': {
 					const flushedData = flush();
-					result = { flushedData };
+					result = {
+						type: command.type,
+						flushedData,
+					};
 					transferables.push(flushedData);
 				}; break;
 			}

packages/mp3-encoder/src/index.ts

@@ -80,6 +80,12 @@ class Mp3Encoder extends CustomAudioEncoder {
 			},
 		});
 
+		this.resetInternalState();
+	}
+
+	private resetInternalState() {
+		this.currentBufferOffset = 0;
+		this.currentTimestamp = null;
 		this.chunkMetadata = {
 			decoderConfig: {
 				codec: 'mp3',
@@ -119,15 +125,15 @@ class Mp3Encoder extends CustomAudioEncoder {
 			},
 		}, [audioData]);
 
-		assert('encodedData' in result);
 		this.digestOutput(new Uint8Array(result.encodedData));
 	}
 
 	async flush() {
 		const result = await this.sendCommand({ type: 'flush' });
 
-		assert('flushedData' in result);
 		this.digestOutput(new Uint8Array(result.flushedData));
+
+		this.resetInternalState();
 	}
 
 	close() {
@@ -171,9 +177,7 @@ class Mp3Encoder extends CustomAudioEncoder {
 			const duration = header.audioSamplesInFrame / header.sampleRate;
 			this.onPacket(new EncodedPacket(data, 'key', this.currentTimestamp, duration), this.chunkMetadata);
 
-			if (this.currentTimestamp === 0) {
-				this.chunkMetadata = {}; // Mimic WebCodecs-like behavior
-			}
+			this.chunkMetadata = {}; // Mimic WebCodecs-like behavior
 
 			this.currentTimestamp += duration;
 			pos += header.totalSize;
@@ -186,13 +190,16 @@ class Mp3Encoder extends CustomAudioEncoder {
 		}
 	}
 
-	private sendCommand(
-		command: WorkerCommand,
+	private sendCommand<T extends string>(
+		command: WorkerCommand & { type: T },
 		transferables?: Transferable[],
 	) {
-		return new Promise<WorkerResponseData>((resolve, reject) => {
+		return new Promise<WorkerResponseData & { type: T }>((resolve, reject) => {
 			const id = this.nextMessageId++;
-			this.pendingMessages.set(id, { resolve, reject });
+			this.pendingMessages.set(id, {
+				resolve: resolve as (value: WorkerResponseData) => void,
+				reject,
+			});
 
 			assert(this.worker);
 

packages/mp3-encoder/src/shared.ts

@@ -24,10 +24,13 @@ export type WorkerCommand = {
 };
 
 export type WorkerResponseData = {
+	type: 'init';
 	success: boolean;
 } | {
+	type: 'encode';
 	encodedData: ArrayBuffer;
 } | {
+	type: 'flush';
 	flushedData: ArrayBuffer;
 };
 

packages/mp3-encoder/tsconfig.json

@@ -1,7 +1,8 @@
 {
-	"extends": "../../../tsconfig.json",
+	"extends": "../../tsconfig.json",
 	"compilerOptions": {
-		"outDir": "../dist/modules",
+		"composite": true,
+		"outDir": "./dist/modules",
 		"declaration": true,
 		"declarationMap": true,
 		"stripInternal": true,
@@ -10,14 +11,15 @@
 		"module": "nodenext",
 		"allowJs": true,
 		"paths": {
-			"mediabunny": ["../../../src/index.ts"],
+			"mediabunny": ["../../src/index.ts"],
 		},
 	},
 	"include": [
-		"**/*",
-		"../../../shared/**/*"
+		"./src/**/*",
+		"./build/**/*",
+		"../../shared/**/*",
 	],
 	"references": [
-        { "path": "../../../src" }
+        { "path": "../../src" }
     ]
-}
+}

packages/mp3-encoder/tsdoc.json

@@ -0,0 +1,4 @@
+{
+    "$schema": "https://developer.microsoft.com/json-schemas/tsdoc/v0/tsdoc.schema.json",
+    "extends": ["../../tsdoc.json"]
+}