Reputation: 13546
In my landscape-only iPhone application, I launch a UIImagePickerController to take a photo, but the live image displayed from the camera is in portrait orientation, with blank space around it. The image is rotated.
Once the camera button is pressed, the preview is very messy, with most of the preview off screen, and views not correctly aligned.
Apple has acknowledged that this is defect, and is working on it.
My question is, does anyone have a work-around (legal or illegal) that would allow me to get this working now. I wouldn't release to the App Store with an illegal fix, but I would have a much better app for user testing - currently the camera is pretty much unusable in landscape.
I will attach a simple test project and images if I can.
Edit - just to clarify, the image I get is correctly landscape. I want the camera & preview UIs to look right!
Upvotes: 46
Views: 39909
Reputation: 3099
Let me know if this is discouraged re-posting the best answer above, I have a 2019 swift version for Alex Wayne's answer.
/**
Scale and rotate a UIImage so that it is correctly oriented
:param: image: The image to be rotated
:returns: UIImage
*/
func scaleAndRotateImage(_ image: UIImage) -> UIImage {
let kMaxResolution: CGFloat = 640
let imgRef: CGImage = image.cgImage!
let width: CGFloat = CGFloat(imgRef.width)
let height: CGFloat = CGFloat(imgRef.height)
var transform: CGAffineTransform = CGAffineTransform.identity
var bounds: CGRect = CGRect(x: 0, y: 0, width: width, height: height)
if width > kMaxResolution || height > kMaxResolution {
let ratio: CGFloat = width / height
if ratio > 1 {
bounds.size.width = kMaxResolution
bounds.size.height = (bounds.size.width / ratio)
}
else {
bounds.size.height = kMaxResolution
bounds.size.width = (bounds.size.height * ratio)
}
}
let scaleRatio: CGFloat = bounds.size.width / width
let imageSize: CGSize = CGSize(width: CGFloat(imgRef.width), height: CGFloat(imgRef.height))
var boundHeight: CGFloat
let orient: UIImage.Orientation = image.imageOrientation
switch orient {
case UIImageOrientation.up:
transform = CGAffineTransform.identity
case UIImageOrientation.upMirrored:
transform = CGAffineTransform(translationX: imageSize.width, y: 0.0)
transform = transform.scaledBy(x: -1.0, y: 1.0)
case UIImageOrientation.down:
transform = CGAffineTransform(translationX: imageSize.width, y: imageSize.height)
transform = transform.rotated(by: CGFloat(Double.pi))
case UIImageOrientation.downMirrored:
transform = CGAffineTransform(translationX: 0.0, y: imageSize.height)
transform = transform.scaledBy(x: 1.0, y: -1.0)
case UIImageOrientation.leftMirrored:
boundHeight = bounds.size.height
bounds.size.height = bounds.size.width
bounds.size.width = boundHeight
transform = CGAffineTransform(translationX: imageSize.height, y: imageSize.width)
transform = transform.scaledBy(x: -1.0, y: 1.0)
transform = transform.rotated(by: CGFloat(3.0 * .pi / 2.0))
case UIImageOrientation.left:
boundHeight = bounds.size.height
bounds.size.height = bounds.size.width
bounds.size.width = boundHeight
transform = CGAffineTransform(translationX: 0.0, y: imageSize.width)
transform = transform.rotated(by: CGFloat(3.0 * .pi / 2.0))
case UIImageOrientation.rightMirrored:
boundHeight = bounds.size.height
bounds.size.height = bounds.size.width
bounds.size.width = boundHeight
transform = CGAffineTransform(scaleX: -1.0, y: 1.0)
transform = transform.rotated(by: CGFloat(.pi / 2.0))
case UIImageOrientation.right:
boundHeight = bounds.size.height
bounds.size.height = bounds.size.width
bounds.size.width = boundHeight
transform = CGAffineTransform(translationX: imageSize.height, y: 0.0)
transform = transform.rotated(by: CGFloat(.pi / 2.0))
}
UIGraphicsBeginImageContext(bounds.size)
let context: CGContext = UIGraphicsGetCurrentContext()!
if orient == UIImage.Orientation.right || orient == UIImage.Orientation.left {
context.scaleBy(x: -scaleRatio, y: scaleRatio)
context.translateBy(x: -height, y: 0)
}
else {
context.scaleBy(x: scaleRatio, y: -scaleRatio)
context.translateBy(x: 0, y: -height)
}
context.concatenate(transform)
UIGraphicsGetCurrentContext()?.draw(imgRef, in: CGRect(x: 0, y: 0, width: width, height: height))
let imageCopy: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
UIGraphicsEndImageContext()
return imageCopy
}
Upvotes: 1
Reputation: 27428
This issue can be resolved by setting modalPresentationStyle
to overCurrentContext
as below,
picker.modalPresentationStyle = .overCurrentContext
and presenting your image picker on Main Thread
like,
DispatchQueue.main.async {
self.present(picker, animated: true) {
}
}
Why this is happening?
Because ImagePickerController
only works in portrait mode and when you trying to present picker from landscape viewcontroller it's try to set your statusbar in portrait mode. So, If you set modalPresentationStyle
to overCurrentContext
then it will not try to set orientation. It will consider current orientation.
see the Apple guide line for ImagePickerController
. It states,
The UIImagePickerController class supports portrait mode only. This class is intended to be used as-is and does not support subclassing. The view hierarchy for this class is private and must not be modified, with one exception. You can assign a custom view to the cameraOverlayView property and use that view to present additional information or manage the interactions between the camera interface and your code.
Upvotes: 0
Reputation: 2440
You'll need to set custom view (with toolbar and title) as cameraOverlayView
, also you'll need to set allowsEditing
and showsCameraControls
to NO
as that will hide standard controls and the preview.
That's what I've found as necessary in app I'm making (thought I need the picker to be in portrait, but I need it to apply some ui changes if user rotate his device to landscape).
Code may be provided if there's need for it.
P.S. There are still some bugs in my code, but I'm working on it :)
Upvotes: 0
Reputation: 1305
I solved this issue by making the UIImagePickerController
appear in full-screen mode, which is also what Apple recommends for iPad.
From UIImagePickerController
documentation:
On iPad, if you specify a source type of UIImagePickerControllerSourceTypeCamera, you can present the image picker modally (full-screen) or by using a popover. However, Apple recommends that you present the camera interface only full-screen.
Upvotes: 1
Reputation: 4063
I don't want to rotate the image after capture; I want to have the preview show correctly in landscape mode. So in iOS 6, I allow portrait mode at the application level, but set the app's root view controller to be of class MyNonrotatingNavigationController
, defined as follows:
@implementation MyNonrotatingNavigationController
-(NSUInteger) supportedInterfaceOrientations
{
return UIInterfaceOrientationMaskLandscape;
}
@end
So everything that's ever shown inside this nav controller will be in landscape orientation (you could do this with any view controller). Now, when I need to show an image picker, I replace the app window's root view controller with a generic one that supports portrait mode. To prevent the old root view controller and its views from deallocating, I maintain pointers to them until I'm ready to put them back in the app window.
#define APP_DELEGATE ((MyAppDelegate*)[[UIApplication sharedApplication] delegate])
static UIViewController *pickerContainer = nil;
static UIViewController *oldRoot = nil;
static UIView *holdView = nil;
-(void) showPicker
{
...create UIImagePickerController...
oldRoot = APP_DELEGATE.window.rootViewController;
holdView = [[UIView alloc] initWithFrame:APP_DELEGATE.window.bounds];
[holdView addSubview:oldRoot.view];
pickerContainer = [UIViewController new];
pickerContainer.view = [[UIView alloc] initWithFrame:APP_DELEGATE.window.bounds];
APP_DELEGATE.window.rootViewController = pickerContainer;
[pickerContainer presentViewController:picker animated:YES completion:NULL];
}
-(void) imagePickerController:(UIImagePickerController*)picker didFinishPickingMediaWithInfo:(NSDictionary*)info
{
[pickerContainer dismissViewControllerAnimated:YES completion:^{
dispatch_async( dispatch_get_main_queue(), ^{
APP_DELEGATE.window.rootViewController = oldRoot;
[APP_DELEGATE.window addSubview:oldRoot.view];
pickerContainer = nil;
oldRoot = nil;
holdView = nil;
});
}];
}
Kind of a pain, but it does seem to work for both photos and videos. The image picker's controls show in portrait mode, but the rest of the app is landscape-only.
Upvotes: 1
Reputation: 11
I don't think that you need the extra work to deal with imageRotation or the EXIF data at all. Image drawInRect will take care of that automatically.
So, you only need to get this size or the image and redraw it to a new image, that would be enough.
Upvotes: 1
Reputation: 187024
The answer is more ridiculous than you might think. I had the same problem and found a solution in a forum somewhere. Pass your taken image into a method like this:
// Code from: http://discussions.apple.com/thread.jspa?messageID=7949889
- (UIImage *)scaleAndRotateImage:(UIImage *)image {
int kMaxResolution = 640; // Or whatever
CGImageRef imgRef = image.CGImage;
CGFloat width = CGImageGetWidth(imgRef);
CGFloat height = CGImageGetHeight(imgRef);
CGAffineTransform transform = CGAffineTransformIdentity;
CGRect bounds = CGRectMake(0, 0, width, height);
if (width > kMaxResolution || height > kMaxResolution) {
CGFloat ratio = width/height;
if (ratio > 1) {
bounds.size.width = kMaxResolution;
bounds.size.height = roundf(bounds.size.width / ratio);
}
else {
bounds.size.height = kMaxResolution;
bounds.size.width = roundf(bounds.size.height * ratio);
}
}
CGFloat scaleRatio = bounds.size.width / width;
CGSize imageSize = CGSizeMake(CGImageGetWidth(imgRef), CGImageGetHeight(imgRef));
CGFloat boundHeight;
UIImageOrientation orient = image.imageOrientation;
switch(orient) {
case UIImageOrientationUp: //EXIF = 1
transform = CGAffineTransformIdentity;
break;
case UIImageOrientationUpMirrored: //EXIF = 2
transform = CGAffineTransformMakeTranslation(imageSize.width, 0.0);
transform = CGAffineTransformScale(transform, -1.0, 1.0);
break;
case UIImageOrientationDown: //EXIF = 3
transform = CGAffineTransformMakeTranslation(imageSize.width, imageSize.height);
transform = CGAffineTransformRotate(transform, M_PI);
break;
case UIImageOrientationDownMirrored: //EXIF = 4
transform = CGAffineTransformMakeTranslation(0.0, imageSize.height);
transform = CGAffineTransformScale(transform, 1.0, -1.0);
break;
case UIImageOrientationLeftMirrored: //EXIF = 5
boundHeight = bounds.size.height;
bounds.size.height = bounds.size.width;
bounds.size.width = boundHeight;
transform = CGAffineTransformMakeTranslation(imageSize.height, imageSize.width);
transform = CGAffineTransformScale(transform, -1.0, 1.0);
transform = CGAffineTransformRotate(transform, 3.0 * M_PI / 2.0);
break;
case UIImageOrientationLeft: //EXIF = 6
boundHeight = bounds.size.height;
bounds.size.height = bounds.size.width;
bounds.size.width = boundHeight;
transform = CGAffineTransformMakeTranslation(0.0, imageSize.width);
transform = CGAffineTransformRotate(transform, 3.0 * M_PI / 2.0);
break;
case UIImageOrientationRightMirrored: //EXIF = 7
boundHeight = bounds.size.height;
bounds.size.height = bounds.size.width;
bounds.size.width = boundHeight;
transform = CGAffineTransformMakeScale(-1.0, 1.0);
transform = CGAffineTransformRotate(transform, M_PI / 2.0);
break;
case UIImageOrientationRight: //EXIF = 8
boundHeight = bounds.size.height;
bounds.size.height = bounds.size.width;
bounds.size.width = boundHeight;
transform = CGAffineTransformMakeTranslation(imageSize.height, 0.0);
transform = CGAffineTransformRotate(transform, M_PI / 2.0);
break;
default:
[NSException raise:NSInternalInconsistencyException format:@"Invalid image orientation"];
}
UIGraphicsBeginImageContext(bounds.size);
CGContextRef context = UIGraphicsGetCurrentContext();
if (orient == UIImageOrientationRight || orient == UIImageOrientationLeft) {
CGContextScaleCTM(context, -scaleRatio, scaleRatio);
CGContextTranslateCTM(context, -height, 0);
}
else {
CGContextScaleCTM(context, scaleRatio, -scaleRatio);
CGContextTranslateCTM(context, 0, -height);
}
CGContextConcatCTM(context, transform);
CGContextDrawImage(UIGraphicsGetCurrentContext(), CGRectMake(0, 0, width, height), imgRef);
UIImage *imageCopy = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return imageCopy;
}
:(
Upvotes: 88