在全屏中导出视频和AVAssetExportSession。

i'm trying to do some animations to a video (after recording) and then export it. but before any animation i had the problem with the orientation which became landscape (without export it was portrait) and it is solved not but now i have problem with making it full screen.in iphone 6,7 plus its full screen how ever in ipad it is not.i'm trying to do some animations to a video (af