Add WebP2 support

src/codecs/wp2/decoder.ts

@@ -0,0 +1,20 @@
+import wp2_dec, { WP2Module } from '../../../codecs/wp2/dec/wp2_dec';
+import wasmUrl from '../../../codecs/wp2/dec/wp2_dec.wasm';
+import { initEmscriptenModule } from '../util';
+
+let emscriptenModule: Promise<WP2Module>;
+
+export async function decode(data: ArrayBuffer): Promise<ImageData> {
+  if (!emscriptenModule) emscriptenModule = initEmscriptenModule(wp2_dec, wasmUrl);
+
+  const module = await emscriptenModule;
+  const rawImage = module.decode(data);
+  const result = new ImageData(
+    new Uint8ClampedArray(rawImage.buffer),
+    rawImage.width,
+    rawImage.height,
+  );
+
+  module.free_result();
+  return result;
+}