ScreenCapturerExample

Twilio Video Screen Capturer Example

NOTE: TVIScreenCapturer has been removed in 3.x. If you wish to share the contents of the entire screen we recommend that you use ReplayKit instead. Take a look at our ReplayKit example app to get started.

This project demonstrates how to write your own TVIVideoSource to capture the contents of a WKWebView using the snasphotting APIs available in WebKit.framework. Since snapshots include only a subset of the view hierarchy, they do offer some flexibility over screen sharing solutions like ReplayKit.

Setup

This example does not connect to a Room, and thus does not require any access tokens or other configuration. Internet connectivity is required to load the contents of the WKWebView. Any device or simulator with iOS 11.0 or later may be used.

FAQ

1. When should I use ReplayKitVideoSource vs ExampleWebViewSource?

Using ReplayKit means that you will require user consent in order to begin recording. Also, video captured by ReplayKit.framework includes your application's entire UIWindow, and the status bar.

If you only want to share a portion of the view hierarchy, and can accept some performance penalty consider writing a use-case based TVIVideoSource (like ExampleWebViewSource) instead.

Known Issues

1. Snapshots captured on iOS simulators appear to include pre-multiplied alpha, but the alpha channel is always opaque (0xFF). Without proper alpha information it is impossible to un-premultiply the data and the images look too dim. This issue does not occur on a real device.