ImageCapture.grabFrame()

This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The grabFrame() property of the ImageCapture interface takes a snapshot of the live video in a MediaStreamTrack, returning an ImageBitmap, if successful.

Syntax

var imageBitmap = ImageCapture.grabFrame()

Parameters

None.

Return value

An ImageBitmap object.

Example

This example is extracted from this Simple Image Capture demo. It shows how to use the Promise returned by grabFrame() to copy the returned frame to a <canvas> element. For simplicy it does not show how to instantiate the image capture object.

var grabFrameButton = document.querySelector('button#grabFrame');
var canvas = document.querySelector('canvas');

grabFrameButton.onclick = grabFrame;

function grabFrame() {
  imageCapture.grabFrame()
  .then(function(imageBitmap) {
    console.log('Grabbed frame:', imageBitmap);
    canvas.width = imageBitmap.width;
    canvas.height = imageBitmap.height;
    canvas.getContext('2d').drawImage(imageBitmap, 0, 0);
    canvas.classList.remove('hidden');
  })
  .catch(function(error) {
    console.log('grabFrame() error: ', error);
  });
}

Specifications

Specification Status Comment
MediaStream Image Capture
The definition of 'grabFrame()' in that specification.
Working Draft Initial definition.

Browser Compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 59 ? ? 46 ?
Feature Android Webview Chrome for Android Firefox Mobile (Gecko) Firefox OS IE Mobile Opera Mobile Safari Mobile
Basic support 59 59 ? ? ? 46 ?

Document Tags and Contributors

 Contributors to this page: jpmedley
 Last updated by: jpmedley,