Features folder

src/features/encoders/mozjpeg/worker/mozjpegEncode.ts

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+/**
+ * Copyright 2020 Google Inc. All Rights Reserved.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import mozjpeg_enc, {
+  MozJPEGModule,
+  EncodeOptions,
+} from 'codecs/mozjpeg_enc/mozjpeg_enc';
+import wasmUrl from 'url:codecs/mozjpeg_enc/mozjpeg_enc.wasm';
+import { initEmscriptenModule } from 'features/util';
+
+let emscriptenModule: Promise<MozJPEGModule>;
+
+export default async function encode(
+  data: ImageData,
+  options: EncodeOptions,
+): Promise<ArrayBuffer> {
+  if (!emscriptenModule) {
+    emscriptenModule = initEmscriptenModule(mozjpeg_enc, wasmUrl);
+  }
+
+  const module = await emscriptenModule;
+  const resultView = module.encode(data.data, data.width, data.height, options);
+  // wasm can’t run on SharedArrayBuffers, so we hard-cast to ArrayBuffer.
+  return resultView.buffer as ArrayBuffer;
+}