Transcode heic/heif images

ts/workers/heicConverterWorker.ts

@@ -0,0 +1,39 @@
+// Copyright 2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import heicConvert from 'heic-convert';
+import { parentPort } from 'worker_threads';
+
+import {
+  WrappedWorkerRequest,
+  WrappedWorkerResponse,
+} from './heicConverterMain';
+
+if (!parentPort) {
+  throw new Error('Must run as a worker thread');
+}
+
+const port = parentPort;
+
+function respond(uuid: string, error: Error | undefined, response?: File) {
+  const wrappedResponse: WrappedWorkerResponse = {
+    uuid,
+    error: error ? error.stack : undefined,
+    response,
+  };
+  port.postMessage(wrappedResponse);
+}
+
+port.on('message', async ({ uuid, data }: WrappedWorkerRequest) => {
+  try {
+    const file = await heicConvert({
+      buffer: new Uint8Array(data),
+      format: 'JPEG',
+      quality: 0.75,
+    });
+
+    respond(uuid, undefined, file);
+  } catch (error) {
+    respond(uuid, error, undefined);
+  }
+});