UIImagePickerController doesn't fill screen

Scaling by a fixed value isn't a good idea... as I'm sure anyone who used the accepted answer here probably found out when the iPhone 5 came out.

Here's a code snippet to scale dynamically based on the screen resolution to eliminate the letter boxing.

// Device's screen size (ignoring rotation intentionally):
CGSize screenSize = [[UIScreen mainScreen] bounds].size;

// iOS is going to calculate a size which constrains the 4:3 aspect ratio
// to the screen size. We're basically mimicking that here to determine
// what size the system will likely display the image at on screen.
// NOTE: screenSize.width may seem odd in this calculation - but, remember,
// the devices only take 4:3 images when they are oriented *sideways*.
float cameraAspectRatio = 4.0 / 3.0;
float imageWidth = floorf(screenSize.width * cameraAspectRatio);
float scale = ceilf((screenSize.height / imageWidth) * 10.0) / 10.0;

self.ipc.cameraViewTransform = CGAffineTransformMakeScale(scale, scale);

The camera's aspect ratio is 4:3 and the screen's aspect ratio is 3:2. So there is simply no way for the camera picture to fill the screen unless you're willing to crop is to 3:2. To do that, apply an appropriate scale transform.

Hey I saw some people were still getting the black bar at the bottom after calculating the scale for the iPhone 5. I had this problem for a while but then I figured out you have to translate the view so it is in the middle of the screen and then apply the scale. Here is my code for doing those two things and it works for me!

    CGSize screenBounds = [UIScreen mainScreen].bounds.size;

    CGFloat cameraAspectRatio = 4.0f/3.0f;

    CGFloat camViewHeight = screenBounds.width * cameraAspectRatio;
    CGFloat scale = screenBounds.height / camViewHeight;

    m_imagePickerController.cameraViewTransform = CGAffineTransformMakeTranslation(0, (screenBounds.height - camViewHeight) / 2.0);
    m_imagePickerController.cameraViewTransform = CGAffineTransformScale(m_imagePickerController.cameraViewTransform, scale, scale);