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 | ? |