iPhone custom camera overlay (plus image processing) : how-to [duplicate]

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How do you create a custom camera view, instead of UIImagePickerViewController?

Many image sharing apps available today from the App Store use a custom camera instead of the standard camera picker provided by Apple.

Does anyone know any tutorials or tips for creating a custom camera?

Yes, create a UIImagePickerController from code, adjust its properties, add an overlay onto it, and with you controller, control whatever you want on that overlay : custom controls, overlaying images, etc...

That gives something like this :

self.picker = [[UIImagePickerController alloc] init];
self.picker.sourceType = UIImagePickerControllerSourceTypeCamera;
self.picker.cameraCaptureMode = UIImagePickerControllerCameraCaptureModePhoto;
self.picker.cameraDevice = UIImagePickerControllerCameraDeviceRear;
self.picker.showsCameraControls = NO;
self.picker.navigationBarHidden = YES;
self.picker.toolbarHidden = YES;
self.picker.wantsFullScreenLayout = YES;

// Insert the overlay
self.overlay = [[OverlayViewController alloc] initWithNibName:@"Overlay" bundle:nil];
self.overlay.pickerReference = self.picker;
self.picker.cameraOverlayView = self.overlay.view;
self.picker.delegate = self.overlay;

[self presentModalViewController:self.picker animated:NO];

OverlayViewController is the controller that you must write to control everything you add onto the overlay.

pickerReference is a property you can keep to send orders to the camera. For example, you could call the following from an IBAction coming from a UIButton placed onto the overlay :