[api-minor] Add an option to set the max canvas area

src/core/evaluator.js

@@ -71,6 +71,7 @@ import { getGlyphsUnicode } from "./glyphlist.js";
 import { getLookupTableFactory } from "./core_utils.js";
 import { getMetrics } from "./metrics.js";
 import { getUnicodeForGlyph } from "./unicode.js";
+import { ImageResizer } from "./image_resizer.js";
 import { MurmurHash3_64 } from "../shared/murmurhash3.js";
 import { OperatorList } from "./operator_list.js";
 import { PDFImage } from "./image.js";
@@ -81,6 +82,7 @@ const DefaultPartialEvaluatorOptions = Object.freeze({
   ignoreErrors: false,
   isEvalSupported: true,
   isOffscreenCanvasSupported: false,
+  canvasMaxAreaInBytes: -1,
   fontExtraProperties: false,
   useSystemFonts: true,
   cMapUrl: null,
@@ -229,6 +231,7 @@ class PartialEvaluator {
     this.parsingType3Font = false;
 
     this._fetchBuiltInCMapBound = this.fetchBuiltInCMap.bind(this);
+    ImageResizer.setMaxArea(this.options.canvasMaxAreaInBytes);
   }
 
   /**

src/core/image_resizer.js

@@ -103,8 +103,17 @@ class ImageResizer {
   }
 
   static set MAX_AREA(area) {
-    this._hasMaxArea = true;
-    shadow(this, "MAX_AREA", area);
+    if (area >= 0) {
+      this._hasMaxArea = true;
+      shadow(this, "MAX_AREA", area);
+    }
+  }
+
+  static setMaxArea(area) {
+    if (!this._hasMaxArea) {
+      // Divide by 4 to have the value in pixels.
+      this.MAX_AREA = area >> 2;
+    }
   }
 
   static _areGoodDims(width, height) {

src/display/api.js

@@ -201,6 +201,9 @@ if (typeof PDFJSDev === "undefined" || !PDFJSDev.test("PRODUCTION")) {
  *   `OffscreenCanvas` in the worker. Primarily used to improve performance of
  *   image conversion/rendering.
  *   The default value is `true` in web environments and `false` in Node.js.
+ * @property {boolean} [canvasMaxAreaInBytes] - The integer value is used to
+ *   know when an image must be resized (uses `OffscreenCanvas` in the worker).
+ *   If it's -1 then a possibly slow algorithm is used to guess the max value.
  * @property {boolean} [disableFontFace] - By default fonts are converted to
  *   OpenType fonts and loaded via the Font Loading API or `@font-face` rules.
  *   If disabled, fonts will be rendered using a built-in font renderer that
@@ -306,6 +309,9 @@ function getDocument(src) {
     typeof src.isOffscreenCanvasSupported === "boolean"
       ? src.isOffscreenCanvasSupported
       : !isNodeJS;
+  const canvasMaxAreaInBytes = Number.isInteger(src.canvasMaxAreaInBytes)
+    ? src.canvasMaxAreaInBytes
+    : -1;
   const disableFontFace =
     typeof src.disableFontFace === "boolean" ? src.disableFontFace : isNodeJS;
   const fontExtraProperties = src.fontExtraProperties === true;
@@ -393,6 +399,7 @@ function getDocument(src) {
       ignoreErrors,
       isEvalSupported,
       isOffscreenCanvasSupported,
+      canvasMaxAreaInBytes,
       fontExtraProperties,
       useSystemFonts,
       cMapUrl: useWorkerFetch ? cMapUrl : null,

web/app.js

@@ -149,6 +149,10 @@ class DefaultExternalServices {
   static updateEditorStates(data) {
     throw new Error("Not implemented: updateEditorStates");
   }
+
+  static get canvasMaxAreaInBytes() {
+    return shadow(this, "canvasMaxAreaInBytes", -1);
+  }
 }
 
 const PDFViewerApplication = {
@@ -945,7 +949,11 @@ const PDFViewerApplication = {
     }
     // Set the necessary API parameters, using all the available options.
     const apiParams = AppOptions.getAll(OptionKind.API);
-    const params = { ...apiParams, ...args };
+    const params = {
+      canvasMaxAreaInBytes: this.externalServices.canvasMaxAreaInBytes,
+      ...apiParams,
+      ...args,
+    };
 
     if (typeof PDFJSDev === "undefined" || !PDFJSDev.test("PRODUCTION")) {
       params.docBaseUrl ||= document.URL.split("#")[0];

web/firefoxcom.js

@@ -434,6 +434,11 @@ class FirefoxExternalServices extends DefaultExternalServices {
     const isInAutomation = FirefoxCom.requestSync("isInAutomation");
     return shadow(this, "isInAutomation", isInAutomation);
   }
+
+  static get canvasMaxAreaInBytes() {
+    const maxArea = FirefoxCom.requestSync("getCanvasMaxArea");
+    return shadow(this, "canvasMaxAreaInBytes", maxArea);
+  }
 }
 PDFViewerApplication.externalServices = FirefoxExternalServices;