second day

view/src/helpers/BuffToImg.ts

@@ -0,0 +1,8 @@
+
+const urlCreator = window.URL || window.webkitURL;
+export default (buff: ArrayBuffer, mimeType: string) => {
+  const blob = new Blob([buff], { type: mimeType });
+  const imageUrl = urlCreator.createObjectURL(blob);
+
+  return imageUrl;
+}

view/src/helpers/CountPixels.ts

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+const worker = new Worker("worker.js");
+
+let i = 0;
+
+let cb = {};
+
+worker.addEventListener("message", ev => {
+  if (ev.data.i in cb) {
+    cb[ev.data.i](ev.data.res);
+  }
+})
+
+export default (arr: ArrayBuffer) => new Promise((res, rej) => {
+  i++;
+  const _i = i;
+  worker.postMessage({ i: _i, arr });
+  cb[_i] = res;
+});

view/src/helpers/FileToImage.ts

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+import bufToImageUrl from "./BuffToImg";
+
+export default (f: File): Promise<Image> => new Promise(async (res, rej) => {
+
+  const arr = await f.arrayBuffer()
+
+  const img = document.createElement("img");
+  img.src = bufToImageUrl(arr, f.type);
+
+  img.onload = async () => {
+    res({
+      id: 0,
+      width: img.width,
+      height: img.height,
+      name: f.name,
+      filename: f.name,
+      type: f.type,
+      colors: [],
+      overlayData: new ArrayBuffer(0),
+      lastModified: f.lastModified,
+      data: arr
+    });
+  };
+
+});

view/src/helpers/index.ts

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+export { default as bufToImageUrl } from "./BuffToImg";
+export { default as fileToImage } from "./FileToImage";
+export { default as countPixels } from "./CountPixels";