feat(packages/excalidraw): expose image size config and optimize resizing (#11332)

packages/excalidraw/data/blob.ts

@@ -311,6 +311,48 @@ export const dataURLToString = (dataURL: DataURL) => {
   return base64ToString(dataURL.slice(dataURL.indexOf(",") + 1));
 };
 
+const getImageFileDimensions = async (file: File) => {
+  const browserURL = typeof window !== "undefined" ? window.URL : undefined;
+  let objectURL: string | null = null;
+  let imageSource: string;
+
+  try {
+    imageSource = browserURL?.createObjectURL
+      ? (objectURL = browserURL.createObjectURL(file))
+      : await getDataURL(file);
+  } catch {
+    objectURL = null;
+    imageSource = await getDataURL(file);
+  }
+
+  return new Promise<{ width: number; height: number }>((resolve, reject) => {
+    const image = new Image();
+
+    const cleanup = () => {
+      image.onload = null;
+      image.onerror = null;
+
+      if (objectURL && browserURL?.revokeObjectURL) {
+        browserURL.revokeObjectURL(objectURL);
+      }
+    };
+
+    image.onload = () => {
+      cleanup();
+      resolve({
+        width: image.naturalWidth || image.width,
+        height: image.naturalHeight || image.height,
+      });
+    };
+    image.onerror = (error) => {
+      cleanup();
+      reject(error);
+    };
+
+    image.src = imageSource;
+  });
+};
+
 export const resizeImageFile = async (
   file: File,
   opts: {
@@ -324,6 +366,20 @@ export const resizeImageFile = async (
     return file;
   }
 
+  if (!isSupportedImageFile(file)) {
+    throw new Error("Error: unsupported file type", { cause: "UNSUPPORTED" });
+  }
+
+  if (!opts.outputType || opts.outputType === file.type) {
+    const dimensions = await getImageFileDimensions(file);
+
+    if (
+      Math.max(dimensions.width, dimensions.height) <= opts.maxWidthOrHeight
+    ) {
+      return file;
+    }
+  }
+
   const [pica, imageBlobReduce] = await Promise.all([
     import("pica").then((res) => res.default),
     // a wrapper for pica for better API
@@ -347,10 +403,6 @@ export const resizeImageFile = async (
     };
   }
 
-  if (!isSupportedImageFile(file)) {
-    throw new Error("Error: unsupported file type", { cause: "UNSUPPORTED" });
-  }
-
   return new File(
     [await reduce.toBlob(file, { max: opts.maxWidthOrHeight, alpha: true })],
     file.name,