OxiPNG + threads PoC

codecs/oxipng/main.js

@@ -0,0 +1,27 @@
+import initOxiPNG, { start_main_thread, optimise } from './pkg/squoosh_oxipng.js';
+import wasmUrl from "./pkg/squoosh_oxipng_bg.wasm";
+
+async function startMainThread() {
+  await initOxiPNG(fetch(wasmUrl));
+  start_main_thread({
+    length: navigator.hardwareConcurrency,
+    pop: () => ({
+      postMessage: data => {
+        postMessage({ type: 'spawn', data });
+      }
+    })
+  });
+  return {
+    optimise
+  };
+}
+
+const mainThread = startMainThread();
+addEventListener('message', async ({ data: { id, args } }) => {
+  try {
+    let result = (await mainThread).optimise(...args);
+    postMessage({ ok: true, id, result });
+  } catch (result) {
+    postMessage({ ok: false, id, result });
+  }
+});