protected String nativeCaptureToDataURL ( CanvasElement canvas , Element element , String mimeType ) { VideoElement videoElement = ( VideoElement ) element ; int width = videoElement . getVideoWidth ( ) ; int height = videoElement . getVideoHeight ( ) ; if ( Double . isNaN ( width ) || Double . isNaN ( height ) ) { width = videoElement . getClientWidth ( ) ; height = videoElement . getClientHeight ( ) ; } canvas . setWidth ( width ) ; canvas . setHeight ( height ) ; Context2d context = canvas . getContext2d ( ) ; context . drawImage ( videoElement , 0 , 0 , width , height ) ; return canvas . toDataUrl ( mimeType ) ; }
Native call to capture the frame of the video stream .