UiVideoEditorController change size

Question

I am captureing video use AVCaptureSession

And then Edit video using UIVideoEditorController

UIVideoEditorController *videoEditor = [[UIVideoEditorController alloc] init];
videoEditor.videoPath = recordedFile.path;
videoEditor.videoQuality = UIImagePickerControllerQualityTypeIFrame960x540;
videoEditor.delegate = self;

However Out video size is always return as 640 *360

Does anyone have idea why?