The grabFrame()
method of the ImageCapture
interface takes a snapshot of the live video in a MediaStreamTrack
and returns a Promise
that resolves with a ImageBitmap
containing the snapshot.
Syntax
const bitmapPromise = imageCapture.grabFrame()
Return value
A Promise
that resolves to 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 ImageCapture
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
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
grabFrame | Chrome Full support 59 | Edge Full support ≤79 | Firefox ? | IE ? | Opera Full support 46 | Safari ? | WebView Android Full support 59 | Chrome Android Full support 59 | Firefox Android ? | Opera Android Full support 43 | Safari iOS ? | Samsung Internet Android Full support 7.0 |
Legend
- Full support
- Full support
- Compatibility unknown
- Compatibility unknown
- Experimental. Expect behavior to change in the future.
- Experimental. Expect behavior to change in the future.