primitive convert from png -> jpg worked

Author: HHMagnus

index.html

@@ -135,7 +135,7 @@ <h1>Offline Image Converter</h1>
 
       // TODO output type should match media type
       function downloadImage(imageData, fileName, outputType) {
-        const blob = new Blob([pdf], { type: outputType });
+        const blob = new Blob([imageData], { type: outputType });
         const url = URL.createObjectURL(blob);
         const a = document.createElement('a');
         a.href = url;
@@ -173,7 +173,7 @@ <h1>Offline Image Converter</h1>
         }
 
         if (type === "done") {
-          downloadPdf(imageData, fileName, outputType);
+          downloadImage(imageData, fileName, outputType);
         } else if (type === "error") {
           showError(message);
         }
@@ -206,9 +206,11 @@ <h1>Offline Image Converter</h1>
         // TODO remove dot from filename if present
         const fileName = file.name;
         const inputType = "png";
-        const imageData = await file.arrayBuffer();
-
-        worker.postMessage({ imageData, fileName, inputType, outputType });
+        const imageDataBuffer = await file.arrayBuffer();
+        const imageData = new Uint8Array(imageDataBuffer);
+        const imageTransfer = imageData.buffer;
+        
+        worker.postMessage({ imageData, fileName, inputType, outputType }, [imageTransfer]);
       }
       window.convert = convert;
 

worker.js

@@ -21,7 +21,7 @@ onmessage = async (event) => {
   try {
     const convertedImage = convert_exposed(imageData, inputType, outputType);
 
-    postMessage({ type: "done", imageData: convertedImage, fileName, outputType }, [mergedPdf.buffer]);
+    postMessage({ type: "done", imageData: convertedImage, fileName, outputType }, [convertedImage.buffer]);
   } catch (err) {
     if (err instanceof WebAssembly.RuntimeError) {
       postMessage({ type: "error", message: "Unexpected WASM exception: " + err.message });