Merge pull request #134 from gianmarco27/canvas2D-willReadFrequently

Fix: set willReadFrequently attribute for multiple readback operations in scan method.
zxing-js · May 22, 2024 · 7631880 · 7631880
2 parents 8f477fa + cee8bbe
commit 7631880
Showing 1 changed file with 7 additions and 2 deletions.
diff --git a/src/readers/BrowserCodeReader.ts b/src/readers/BrowserCodeReader.ts
@@ -1032,8 +1032,13 @@ export class BrowserCodeReader {
     /**
      * The HTML canvas element context.
      */
-    let captureCanvasContext = captureCanvas.getContext('2d');
-
+    let captureCanvasContext;
+    try {
+        captureCanvasContext = elem.getContext('2d', { willReadFrequently: true }) as CanvasRenderingContext2D;
+    } catch (e) {
+        captureCanvasContext = elem.getContext('2d');
+    }
+
     // cannot proceed w/o this
     if (!captureCanvasContext) {
       throw new Error('Couldn\'t create canvas for visual element scan.');