CaptureController: resetZoomLevel() method
Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.
The CaptureController interface's resetZoomLevel() method resets the captured display surface's zoom to its initial level, which is 100.
The resetZoomLevel() method must be invoked via transient activation. In addition, the user is asked for permission to share tabs when screen capture is first attempted; if the user denies permission the zoom level cannot be changed even with transient activation.
Syntax
resetZoomLevel()
Parameters
None.
Return value
Exceptions
InvalidStateErrorDOMException-
An attempt is made to invoke
resetZoomLevel()without transient activation. NotAllowedErrorDOMException-
Thrown when:
- The page's
captured-surface-controlPermissions Policy does not permit the page to use the Captured Surface Control API. - Permission to capture the display surface is explicitly denied by the user.
- The page's
Examples
Basic resetZoomLevel() usage
The following snippet adds an event listener to a button so that when it is clicked, the resetZoom() function is called. This in turn calls the resetZoomLevel() method, resetting the captured surface's zoom level to 100.
// Create controller and start capture
const controller = new CaptureController();
videoElem.srcObject = await navigator.mediaDevices.getDisplayMedia({
controller,
});
// ...
resetBtn.addEventListener("click", resetZoom);
async function resetZoom() {
await controller.resetZoomLevel();
}
See Using the Captured Surface Control API for a full working example.
Specifications
| Specification |
|---|
| Captured Surface Control # dom-capturecontroller-resetzoomlevel |