Initial Commit

packages/media/audio/audio-codecs/src/codecs/aac.ts

@@ -0,0 +1,20 @@
+import { createWasmCodec } from "./wasm-base.js";
+
+function aacMagic(bytes: Uint8Array): boolean {
+    if (bytes.byteLength < 2) return false;
+    // ADTS sync word: 0xFFFx
+    return bytes[0] === 0xff && (bytes[1]! & 0xf0) === 0xf0;
+}
+
+/** Lazy AAC codec backed by `@audio/decode-aac`. Decode-only. */
+export const AacCodec = createWasmCodec({
+    name: "aac",
+    extensions: ["aac", "m4a"],
+    mimeTypes: ["audio/aac", "audio/mp4"],
+    module: "@audio/decode-aac",
+    magic: aacMagic,
+    supportsEncode: false,
+    load: () =>
+        // @ts-expect-error optional dependency resolved at runtime
+        import("@audio/decode-aac"),
+});