Custom shape for camera controller IOS - ios

Question

I am trying to give a round shape to the camera view to take an image. The circle should be of 200 width and 200 height, and when it is open, the user has to be able to still interact with background view. All I have managed until now is:
- (IBAction)useCameraPhoto:(id)sender
{
if ([UIImagePickerController isSourceTypeAvailable:
UIImagePickerControllerSourceTypeCamera])
{
UIImagePickerController *imagePicker =
[[UIImagePickerController alloc] init];
imagePicker.delegate = self;
imagePicker.sourceType =
UIImagePickerControllerSourceTypeCamera;
imagePicker.mediaTypes = [NSArray arrayWithObjects:
(NSString *) kUTTypeImage,
nil];
imagePicker.allowsEditing = YES;
[self presentViewController:imagePicker
animated:YES completion:nil];
newMedia = YES;
}else{
NSLog(#"Camera is not available");
UIAlertView *alert1 = [[UIAlertView alloc] initWithTitle:#"Important message" message:#"Unfortunately the camera is not available on your device." delegate:self cancelButtonTitle:#"Ok" otherButtonTitles: nil];
[alert1 show];
}
}
This code is presenting a viewcontrller from where users can take a shot, but it does not have a round shape.
I thought of doing something like
imagePicker.allowsEditing.frame = CGRectMake (30, 100, 200, 200);
but still this would not give it the round corners. Furthermore the view beneath it, even if visible, does not respond to touch. Any ideas?
EDIT:
I have tried this. It gives round corners but the background is still black
imagePicker.modalTransitionStyle = UIModalTransitionStyleCrossDissolve;
imagePicker.modalPresentationStyle = UIModalPresentationFormSheet;
[self presentViewController:imagePicker animated:YES completion:nil];
imagePicker.view.layer.cornerRadius = 100; // this value vary as per your desire
imagePicker.view.clipsToBounds = YES;
imagePicker.view.frame = CGRectMake(40,40, 200, 200);

Answer 1

Instead of doing a modal pop-up, you can directly add camera support using the AVFoundation. There is a nice iOS camera demo already available for free on the apple developer site.
Then you can attach the preview image to a UIImageView on your UIViewController and do the same thing with its layer to get the desired effect:
imageView.view.layer.cornerRadius = 100; // this value vary as per your desire
imageView.view.clipsToBounds = YES;
imageView.view.frame = CGRectMake(40,40, 200, 200);