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iOS UIImagePickerController result image orientation after upload

I am testing my iPhone application on an iOS 3.1.3 iPhone. I am selecting/capturing an image using a UIImagePickerController:

UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
[imagePicker setSourceType:UIImagePickerControllerSourceTypeCamera];
[imagePicker setDelegate:self];
[self.navigationController presentModalViewController:imagePicker animated:YES];
[imagePicker release];



- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
    self.image = [info objectForKey:UIImagePickerControllerOriginalImage];
    imageView.image = self.image;
    [self.navigationController dismissModalViewControllerAnimated:YES];
    submitButton.enabled = YES;
}

I then at some point send it to my web server using the ASI classes:

ASIFormDataRequest *request = [ASIFormDataRequest requestWithURL:[NSURL URLWithString:@"http://example.com/myscript.php"]];
[request setDelegate:self];
[request setStringEncoding:NSUTF8StringEncoding];
[request setShouldContinueWhenAppEntersBackground:YES];
//other post keys/values
[request setFile:UIImageJPEGRepresentation(self.image, 100.0f) withFileName:[NSString stringWithFormat:@"%d.jpg", [[NSDate date] timeIntervalSinceNow]] andContentType:@"image/jpg" forKey:@"imageFile"];
[request startAsynchronous];

the problem: when i take a picture with the iphone while holding it landscape, the image gets uploaded to the server and it viewed like you would expect. when taking a picture holding the phone in portrait, the image is uploaded and viewed as it had been rotated 90 degrees.

my application is set to only work in portrait modes(upsidedown and regular).

How can i make the image always show the correct orientation after uploading?

the image appears to be correct as displayed in an UIImageView(directly after taking the picture), but viewing on the server says otherwise.


R
Rishil Patel

A UIImage has a property imageOrientation, which instructs the UIImageView and other UIImage consumers to rotate the raw image data. There's a good chance that this flag is being saved to the exif data in the uploaded jpeg image, but the program you use to view it is not honoring that flag.

To rotate the UIImage to display properly when uploaded, you can use a category like this:

UIImage+fixOrientation.h

@interface UIImage (fixOrientation)

- (UIImage *)fixOrientation;

@end

UIImage+fixOrientation.m

@implementation UIImage (fixOrientation)

- (UIImage *)fixOrientation {

    // No-op if the orientation is already correct
    if (self.imageOrientation == UIImageOrientationUp) return self;

    // We need to calculate the proper transformation to make the image upright.
    // We do it in 2 steps: Rotate if Left/Right/Down, and then flip if Mirrored.
    CGAffineTransform transform = CGAffineTransformIdentity;

    switch (self.imageOrientation) {
        case UIImageOrientationDown:
        case UIImageOrientationDownMirrored:
            transform = CGAffineTransformTranslate(transform, self.size.width, self.size.height);
            transform = CGAffineTransformRotate(transform, M_PI);
            break;

        case UIImageOrientationLeft:
        case UIImageOrientationLeftMirrored:
            transform = CGAffineTransformTranslate(transform, self.size.width, 0);
            transform = CGAffineTransformRotate(transform, M_PI_2);
            break;

        case UIImageOrientationRight:
        case UIImageOrientationRightMirrored:
            transform = CGAffineTransformTranslate(transform, 0, self.size.height);
            transform = CGAffineTransformRotate(transform, -M_PI_2);
            break;
        case UIImageOrientationUp:
        case UIImageOrientationUpMirrored:
            break;
    }

    switch (self.imageOrientation) {
        case UIImageOrientationUpMirrored:
        case UIImageOrientationDownMirrored:
            transform = CGAffineTransformTranslate(transform, self.size.width, 0);
            transform = CGAffineTransformScale(transform, -1, 1);
            break;

        case UIImageOrientationLeftMirrored:
        case UIImageOrientationRightMirrored:
            transform = CGAffineTransformTranslate(transform, self.size.height, 0);
            transform = CGAffineTransformScale(transform, -1, 1);
            break;
        case UIImageOrientationUp:
        case UIImageOrientationDown:
        case UIImageOrientationLeft:
        case UIImageOrientationRight:
            break;
    }

    // Now we draw the underlying CGImage into a new context, applying the transform
    // calculated above.
    CGContextRef ctx = CGBitmapContextCreate(NULL, self.size.width, self.size.height,
                                             CGImageGetBitsPerComponent(self.CGImage), 0,
                                             CGImageGetColorSpace(self.CGImage),
                                             CGImageGetBitmapInfo(self.CGImage));
    CGContextConcatCTM(ctx, transform);
    switch (self.imageOrientation) {
        case UIImageOrientationLeft:
        case UIImageOrientationLeftMirrored:
        case UIImageOrientationRight:
        case UIImageOrientationRightMirrored:
            // Grr...
            CGContextDrawImage(ctx, CGRectMake(0,0,self.size.height,self.size.width), self.CGImage);
            break;

        default:
            CGContextDrawImage(ctx, CGRectMake(0,0,self.size.width,self.size.height), self.CGImage);
            break;
    }

    // And now we just create a new UIImage from the drawing context
    CGImageRef cgimg = CGBitmapContextCreateImage(ctx);
    UIImage *img = [UIImage imageWithCGImage:cgimg];
    CGContextRelease(ctx);
    CGImageRelease(cgimg);
    return img;
}

@end

thanks, worked perfect. never used a category or understood them until now!
@Anomie It's hard for me to explain how happy you just made me. Your answer saved my day. Thank you very much.
I tried the same, works perfect but it taking appx 2-3 seconds to rotate 3264*2448 resolution images. So please suggest improved version.
I consider stackoverflow.com/questions/8915630/… a better answer
There is yet another solution to this problem here (quite similar to this one) that includes a lengthy discussion of what's actually going on.
a
an0

I figured out a much simpler one:

- (UIImage *)normalizedImage {
    if (self.imageOrientation == UIImageOrientationUp) return self; 

    UIGraphicsBeginImageContextWithOptions(self.size, NO, self.scale);
    [self drawInRect:(CGRect){0, 0, self.size}];
    UIImage *normalizedImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return normalizedImage;
}

BTW: @Anomie's code does not take scale into account, so will not work for 2x images.


How do you use it in the code? I have this one: UIImageJPEGRepresentation(image, 90); where the image is an UIImage
@Odelya Add this method to your UIImage category then call [image normalizedImage]. Or use the code of the method directly by replacing self with your UIImage object.
@an0 The method takes about a second which consumes time. Is there a way to improve it?
Thanks for that.From my tests it look like this method is a bit faster than the chosen answer, something like 20% on my iphone4.
There is yet another solution to this problem here along with a lengthy explanation of what's going on.
T
Tamás Sengel

Here is a Swift version of the answer by @an0:

func normalizedImage() -> UIImage {

  if (self.imageOrientation == UIImageOrientation.Up) { 
      return self;
  }

  UIGraphicsBeginImageContextWithOptions(self.size, false, self.scale);
  let rect = CGRect(x: 0, y: 0, width: self.size.width, height: self.size.height)
  self.drawInRect(rect)

  let normalizedImage : UIImage = UIGraphicsGetImageFromCurrentImageContext()
  UIGraphicsEndImageContext();
  return normalizedImage;
}

Also in a more general function:

func fixOrientation(img:UIImage) -> UIImage {

  if (img.imageOrientation == UIImageOrientation.Up) { 
      return img;
  }

  UIGraphicsBeginImageContextWithOptions(img.size, false, img.scale);
  let rect = CGRect(x: 0, y: 0, width: img.size.width, height: img.size.height)
  img.drawInRect(rect)

  let normalizedImage : UIImage = UIGraphicsGetImageFromCurrentImageContext()
  UIGraphicsEndImageContext();
  return normalizedImage;

}

Swift 3 version:

func fixOrientation(img: UIImage) -> UIImage {
    if (img.imageOrientation == .up) {
        return img
    }

    UIGraphicsBeginImageContextWithOptions(img.size, false, img.scale)
    let rect = CGRect(x: 0, y: 0, width: img.size.width, height: img.size.height)
    img.draw(in: rect)

    let normalizedImage = UIGraphicsGetImageFromCurrentImageContext()!
    UIGraphicsEndImageContext()

    return normalizedImage
}

Rare that you need to scroll all the way to the bottom for the best answer. +1!
where should i use fixOrientation? I have a saveImage function, should i use it there or on my imageHolder.image?
If you want to use the more general function above then yes you could use it in your saveImage function. Just pass fixOrientation your UIImage object and it will return a correctly oriented version of the UIImage you passed into it.
Thanks for the Swift 3 version
p
pgb

Solution for Swift 3.1 for orientation issue while capturing the image from Camera.

I have updated the solution given by jake and Metal Heart

UIImage extension

//MARK:- Image Orientation fix

extension UIImage {

    func fixOrientation() -> UIImage {

        // No-op if the orientation is already correct
        if ( self.imageOrientation == UIImageOrientation.up ) {
            return self;
        }

        // We need to calculate the proper transformation to make the image upright.
        // We do it in 2 steps: Rotate if Left/Right/Down, and then flip if Mirrored.
        var transform: CGAffineTransform = CGAffineTransform.identity

        if ( self.imageOrientation == UIImageOrientation.down || self.imageOrientation == UIImageOrientation.downMirrored ) {
            transform = transform.translatedBy(x: self.size.width, y: self.size.height)
            transform = transform.rotated(by: CGFloat(Double.pi))
        }

        if ( self.imageOrientation == UIImageOrientation.left || self.imageOrientation == UIImageOrientation.leftMirrored ) {
            transform = transform.translatedBy(x: self.size.width, y: 0)
            transform = transform.rotated(by: CGFloat(Double.pi / 2.0))
        }

        if ( self.imageOrientation == UIImageOrientation.right || self.imageOrientation == UIImageOrientation.rightMirrored ) {
            transform = transform.translatedBy(x: 0, y: self.size.height);
            transform = transform.rotated(by: CGFloat(-Double.pi / 2.0));
        }

        if ( self.imageOrientation == UIImageOrientation.upMirrored || self.imageOrientation == UIImageOrientation.downMirrored ) {
            transform = transform.translatedBy(x: self.size.width, y: 0)
            transform = transform.scaledBy(x: -1, y: 1)
        }

        if ( self.imageOrientation == UIImageOrientation.leftMirrored || self.imageOrientation == UIImageOrientation.rightMirrored ) {
            transform = transform.translatedBy(x: self.size.height, y: 0);
            transform = transform.scaledBy(x: -1, y: 1);
        }

        // Now we draw the underlying CGImage into a new context, applying the transform
        // calculated above.
        let ctx: CGContext = CGContext(data: nil, width: Int(self.size.width), height: Int(self.size.height),
                                                      bitsPerComponent: self.cgImage!.bitsPerComponent, bytesPerRow: 0,
                                                      space: self.cgImage!.colorSpace!,
                                                      bitmapInfo: self.cgImage!.bitmapInfo.rawValue)!;

        ctx.concatenate(transform)

        if ( self.imageOrientation == UIImageOrientation.left ||
            self.imageOrientation == UIImageOrientation.leftMirrored ||
            self.imageOrientation == UIImageOrientation.right ||
            self.imageOrientation == UIImageOrientation.rightMirrored ) {
            ctx.draw(self.cgImage!, in: CGRect(x: 0,y: 0,width: self.size.height,height: self.size.width))
        } else {
            ctx.draw(self.cgImage!, in: CGRect(x: 0,y: 0,width: self.size.width,height: self.size.height))
        }

        // And now we just create a new UIImage from the drawing context and return it
        return UIImage(cgImage: ctx.makeImage()!)
    }
}

Swift 2.0

//MARK:- Image Orientation fix

extension UIImage {

    func fixOrientation() -> UIImage {

        // No-op if the orientation is already correct
        if ( self.imageOrientation == UIImageOrientation.Up ) {
            return self;
        }

        // We need to calculate the proper transformation to make the image upright.
        // We do it in 2 steps: Rotate if Left/Right/Down, and then flip if Mirrored.
        var transform: CGAffineTransform = CGAffineTransformIdentity

        if ( self.imageOrientation == UIImageOrientation.Down || self.imageOrientation == UIImageOrientation.DownMirrored ) {
            transform = CGAffineTransformTranslate(transform, self.size.width, self.size.height)
            transform = CGAffineTransformRotate(transform, CGFloat(M_PI))
        }

        if ( self.imageOrientation == UIImageOrientation.Left || self.imageOrientation == UIImageOrientation.LeftMirrored ) {
            transform = CGAffineTransformTranslate(transform, self.size.width, 0)
            transform = CGAffineTransformRotate(transform, CGFloat(M_PI_2))
        }

        if ( self.imageOrientation == UIImageOrientation.Right || self.imageOrientation == UIImageOrientation.RightMirrored ) {
            transform = CGAffineTransformTranslate(transform, 0, self.size.height);
            transform = CGAffineTransformRotate(transform,  CGFloat(-M_PI_2));
        }

        if ( self.imageOrientation == UIImageOrientation.UpMirrored || self.imageOrientation == UIImageOrientation.DownMirrored ) {
            transform = CGAffineTransformTranslate(transform, self.size.width, 0)
            transform = CGAffineTransformScale(transform, -1, 1)
        }

        if ( self.imageOrientation == UIImageOrientation.LeftMirrored || self.imageOrientation == UIImageOrientation.RightMirrored ) {
            transform = CGAffineTransformTranslate(transform, self.size.height, 0);
            transform = CGAffineTransformScale(transform, -1, 1);
        }

        // Now we draw the underlying CGImage into a new context, applying the transform
        // calculated above.
        let ctx: CGContextRef = CGBitmapContextCreate(nil, Int(self.size.width), Int(self.size.height),
            CGImageGetBitsPerComponent(self.CGImage), 0,
            CGImageGetColorSpace(self.CGImage),
            CGImageGetBitmapInfo(self.CGImage).rawValue)!;

        CGContextConcatCTM(ctx, transform)

        if ( self.imageOrientation == UIImageOrientation.Left ||
            self.imageOrientation == UIImageOrientation.LeftMirrored ||
            self.imageOrientation == UIImageOrientation.Right ||
            self.imageOrientation == UIImageOrientation.RightMirrored ) {
                CGContextDrawImage(ctx, CGRectMake(0,0,self.size.height,self.size.width), self.CGImage)
        } else {
            CGContextDrawImage(ctx, CGRectMake(0,0,self.size.width,self.size.height), self.CGImage)
        }

        // And now we just create a new UIImage from the drawing context and return it
        return UIImage(CGImage: CGBitmapContextCreateImage(ctx)!)
    }
}

Use of this UIImage Extension in your code:

let fixOrientationImage=chosenImage.fixOrientation()

place this in your delegate methods of image picker like this

Swift 3.1

//MARK: Image Picker Delegates
    func imagePickerController(
        _ picker: UIImagePickerController,
        didFinishPickingMediaWithInfo info: [String : Any]){
        let chosenImage = info[UIImagePickerControllerOriginalImage] as! UIImage
        profileImg.contentMode = .scaleAspectFill
        let fixOrientationImage=chosenImage.fixOrientation()
        profileImg.image = fixOrientationImage

        dismiss(animated: true, completion: nil)
    }

Swift 2.0

//MARK: Image Picker Delegates
    func imagePickerController(
        picker: UIImagePickerController,
        didFinishPickingMediaWithInfo info: [String : AnyObject])
    {
        let chosenImage = info[UIImagePickerControllerOriginalImage] as! UIImage
        profileImg.contentMode = .ScaleAspectFill
        **//Fix the image orientation**
         let fixOrientationImage=chosenImage.fixOrientation()
        profileImg.image = fixOrientationImage

        dismissViewControllerAnimated(true, completion: nil)
    }

Thanks, this helped me a lot.
Its work. but I wonder is there any approach that can avoid calling the CG related API, as that caused leads to a large amount of memory allocation. It will only be released when we no longer retain the UIImage.
This was working fine up until iOS 10. In iOS 11 after performing this I am getting a black image in return. I have made a small change (replaced M_PI with Double.pi) though. I am using XCode 9 with Swift 3.2.
B
Benjamin

Swift 4.x/5.0 version of @an0 's solution:

extension UIImage {
    func upOrientationImage() -> UIImage? {
        switch imageOrientation {
        case .up:
            return self
        default:
            UIGraphicsBeginImageContextWithOptions(size, false, scale)
            draw(in: CGRect(origin: .zero, size: size))
            let result = UIGraphicsGetImageFromCurrentImageContext()
            UIGraphicsEndImageContext()
            return result
        }
    }
}

Thank you.Its works perfectly.Most underrated answer.
thank you! Calling this function inside imagePickerController and it fixes image orientation
M
MetalHeart2003

in swift ;)

UPDATE SWIFT 3.0 :D

func sFunc_imageFixOrientation(img:UIImage) -> UIImage {


    // No-op if the orientation is already correct
    if (img.imageOrientation == UIImageOrientation.up) {
        return img;
    }
    // We need to calculate the proper transformation to make the image upright.
    // We do it in 2 steps: Rotate if Left/Right/Down, and then flip if Mirrored.
    var transform:CGAffineTransform = CGAffineTransform.identity

    if (img.imageOrientation == UIImageOrientation.down
        || img.imageOrientation == UIImageOrientation.downMirrored) {

        transform = transform.translatedBy(x: img.size.width, y: img.size.height)
        transform = transform.rotated(by: CGFloat(M_PI))
    }

    if (img.imageOrientation == UIImageOrientation.left
        || img.imageOrientation == UIImageOrientation.leftMirrored) {

        transform = transform.translatedBy(x: img.size.width, y: 0)
        transform = transform.rotated(by: CGFloat(M_PI_2))
    }

    if (img.imageOrientation == UIImageOrientation.right
        || img.imageOrientation == UIImageOrientation.rightMirrored) {

        transform = transform.translatedBy(x: 0, y: img.size.height);
        transform = transform.rotated(by: CGFloat(-M_PI_2));
    }

    if (img.imageOrientation == UIImageOrientation.upMirrored
        || img.imageOrientation == UIImageOrientation.downMirrored) {

        transform = transform.translatedBy(x: img.size.width, y: 0)
        transform = transform.scaledBy(x: -1, y: 1)
    }

    if (img.imageOrientation == UIImageOrientation.leftMirrored
        || img.imageOrientation == UIImageOrientation.rightMirrored) {

        transform = transform.translatedBy(x: img.size.height, y: 0);
        transform = transform.scaledBy(x: -1, y: 1);
    }


    // Now we draw the underlying CGImage into a new context, applying the transform
    // calculated above.
    let ctx:CGContext = CGContext(data: nil, width: Int(img.size.width), height: Int(img.size.height),
                                  bitsPerComponent: img.cgImage!.bitsPerComponent, bytesPerRow: 0,
                                  space: img.cgImage!.colorSpace!,
                                  bitmapInfo: img.cgImage!.bitmapInfo.rawValue)!

    ctx.concatenate(transform)


    if (img.imageOrientation == UIImageOrientation.left
        || img.imageOrientation == UIImageOrientation.leftMirrored
        || img.imageOrientation == UIImageOrientation.right
        || img.imageOrientation == UIImageOrientation.rightMirrored
        ) {


        ctx.draw(img.cgImage!, in: CGRect(x:0,y:0,width:img.size.height,height:img.size.width))

    } else {
        ctx.draw(img.cgImage!, in: CGRect(x:0,y:0,width:img.size.width,height:img.size.height))
    }


    // And now we just create a new UIImage from the drawing context
    let cgimg:CGImage = ctx.makeImage()!
    let imgEnd:UIImage = UIImage(cgImage: cgimg)

    return imgEnd
}

After weeks of struggling with this issue and trying several other solutions, this one ended up working perfectly. If I could up vote +10 I would. Thank you. :)
@MetalHeart2003 this method MASSIVELY increases the file size of my image, Mine went from 200kb to 4mb, is there any way to stop this happening?
@TimWhiting it sounds like you are starting with a compressed image. But this method redraws the rotated image without any compression. You can recompress the bitmap image afterwards with UIImageJPEGRepresentation()
E
Erroneous

I used this page when designing my app that takes pictures and I found that the following method will correct the orientation and use less memory and processor than previous answers:

CGImageRef cgRef = image.CGImage;
image = [[UIImage alloc] initWithCGImage:cgRef scale:1.0 orientation:UIImageOrientationUp];

This basically just rewraps the actual image data with a new orientation. I was using @an0's code but it makes a new image in memory which can be taxing on a 3264x2448 image that you might get from a camera.


I tested this answer with iOS 7.1 on iPhone 5s but it didn't work, in which windows machines [MS-Paint, Win photo Viewer] and UIImageView showed the image with 90 degree orientation from original! note that images taken with default camera touch button, not the volume up.
seems like this just changes the orientation flag...needs to rotate the actual bits
J
Jon

If you enable editing, then the edited image (as opposed to the original) will be oriented as expected:

UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];
imagePickerController.allowsEditing = YES;
// set delegate and present controller

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
    UIImage *photo = [info valueForKey:UIImagePickerControllerEditedImage];
    // do whatever
}

Enabling editing allows the user to resize and move the image before tapping "Use Photo"


Unfortunately this solution does not horizontally flip the image, even allowing editing.
works but forces user to crop images to a square unless you want to add a lot more code to allow variable crop sizes
S
Shekhar Gupta

This what I have found for fixing orientation issue

UIImage *initialImage = [info objectForKey:@"UIImagePickerControllerOriginalImage"];
NSData *data = UIImagePNGRepresentation(self.initialImage);

UIImage *tempImage = [UIImage imageWithData:data];
UIImage *fixedOrientationImage = [UIImage imageWithCGImage:tempImage.CGImage
                                     scale:initialImage.scale
                               orientation:self.initialImage.imageOrientation];
initialImage = fixedOrientationImage;

EDIT:

UIImage *initialImage = [info objectForKey:@"UIImagePickerControllerOriginalImage"];
NSData *data = UIImagePNGRepresentation(self.initialImage);

initialImage = [UIImage imageWithCGImage:[UIImage imageWithData:data].CGImage
                                                     scale:initialImage.scale
                                               orientation:self.initialImage.imageOrientation];

Too much conversion between image to PNG back to image, making way too expensive. @an0 answer is better.
e
emrcftci

I achieve this by writing below a few lines of code

extension UIImage {

    public func correctlyOrientedImage() -> UIImage {
        guard imageOrientation != .up else { return self }

        UIGraphicsBeginImageContextWithOptions(size, false, scale)
        draw(in: CGRect(origin: .zero, size: size))
        let normalizedImage: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
        UIGraphicsEndImageContext()

        return normalizedImage
    }
}

0
0xced

Here’s a solution that doesn’t change the colorspace of the original image. If you want to normalize the orientation of a grayscale image, you are out of luck with all solutions based on UIGraphicsBeginImageContextWithOptions because it creates a context in the RGB colorspace. Instead, you have to create a context with the same properties as the original image and draw:

extension UIImage {
    static let rotatedOrentations: [UIImage.Orientation] = [.left, .leftMirrored, .right, .rightMirrored]

    func normalizedImage() -> UIImage {
        if imageOrientation == .up {
            return self
        }

        let image = self.cgImage!
        let swapOrientation = UIImage.rotatedOrentations.contains(imageOrientation)
        let width = swapOrientation ? image.height : image.width
        let height = swapOrientation ? image.width : image.height
        let context = CGContext(data: nil, width: width, height: height, bitsPerComponent: image.bitsPerComponent, bytesPerRow: image.bytesPerRow, space: image.colorSpace!, bitmapInfo: image.bitmapInfo.rawValue)!
        let flipVertical = CGAffineTransform(a: 1, b: 0, c: 0, d: -1, tx: 0, ty: CGFloat(height));
        context.concatenate(flipVertical)
        UIGraphicsPushContext(context)
        self.draw(at: .zero)
        UIGraphicsPopContext()

        return UIImage(cgImage: context.makeImage()!)
    }
}

Y
Yaroslav

Update for Swift 3.1 based on Sourabh Sharma's answer, with code clean up.

extension UIImage {
    func fixedOrientation() -> UIImage {
        if imageOrientation == .up { return self }

        var transform:CGAffineTransform = .identity
        switch imageOrientation {
        case .down, .downMirrored:
            transform = transform.translatedBy(x: size.width, y: size.height).rotated(by: .pi)
        case .left, .leftMirrored:
            transform = transform.translatedBy(x: size.width, y: 0).rotated(by: .pi/2)
        case .right, .rightMirrored:
            transform = transform.translatedBy(x: 0, y: size.height).rotated(by: -.pi/2)
        default: break
        }

        switch imageOrientation {
        case .upMirrored, .downMirrored:
            transform = transform.translatedBy(x: size.width, y: 0).scaledBy(x: -1, y: 1)
        case .leftMirrored, .rightMirrored:
            transform = transform.translatedBy(x: size.height, y: 0).scaledBy(x: -1, y: 1)
        default: break
        }

        let ctx = CGContext(data: nil, width: Int(size.width), height: Int(size.height),
                                       bitsPerComponent: cgImage!.bitsPerComponent, bytesPerRow: 0,
                                       space: cgImage!.colorSpace!, bitmapInfo: cgImage!.bitmapInfo.rawValue)!
        ctx.concatenate(transform)

        switch imageOrientation {
        case .left, .leftMirrored, .right, .rightMirrored:
            ctx.draw(cgImage!, in: CGRect(x: 0, y: 0, width: size.height,height: size.width))
        default:
            ctx.draw(cgImage!, in: CGRect(x: 0, y: 0, width: size.width,height: size.height))
        }
        return UIImage(cgImage: ctx.makeImage()!)
    }
}

Picker delegate method example:

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
    guard let originalImage = info[UIImagePickerControllerOriginalImage] as? UIImage else { return }
    let fixedImage = originalImage.fixedOrientation()
    // do your work
}

j
jake1981

Here's UIImage extension for swift:

extension UIImage {

    func fixOrientation() -> UIImage {

        // No-op if the orientation is already correct
        if ( self.imageOrientation == UIImageOrientation.Up ) {
            return self;
        }

        // We need to calculate the proper transformation to make the image upright.
        // We do it in 2 steps: Rotate if Left/Right/Down, and then flip if Mirrored.
        var transform: CGAffineTransform = CGAffineTransformIdentity

        if ( self.imageOrientation == UIImageOrientation.Down || self.imageOrientation == UIImageOrientation.DownMirrored ) {
            transform = CGAffineTransformTranslate(transform, self.size.width, self.size.height)
            transform = CGAffineTransformRotate(transform, CGFloat(M_PI))
        }

        if ( self.imageOrientation == UIImageOrientation.Left || self.imageOrientation == UIImageOrientation.LeftMirrored ) {
            transform = CGAffineTransformTranslate(transform, self.size.width, 0)
            transform = CGAffineTransformRotate(transform, CGFloat(M_PI_2))
        }

        if ( self.imageOrientation == UIImageOrientation.Right || self.imageOrientation == UIImageOrientation.RightMirrored ) {
            transform = CGAffineTransformTranslate(transform, 0, self.size.height);
            transform = CGAffineTransformRotate(transform,  CGFloat(-M_PI_2));
        }

        if ( self.imageOrientation == UIImageOrientation.UpMirrored || self.imageOrientation == UIImageOrientation.DownMirrored ) {
            transform = CGAffineTransformTranslate(transform, self.size.width, 0)
            transform = CGAffineTransformScale(transform, -1, 1)
        }

        if ( self.imageOrientation == UIImageOrientation.LeftMirrored || self.imageOrientation == UIImageOrientation.RightMirrored ) {
            transform = CGAffineTransformTranslate(transform, self.size.height, 0);
            transform = CGAffineTransformScale(transform, -1, 1);
        }

        // Now we draw the underlying CGImage into a new context, applying the transform
        // calculated above.
        var ctx: CGContextRef = CGBitmapContextCreate(nil, Int(self.size.width), Int(self.size.height),
            CGImageGetBitsPerComponent(self.CGImage), 0,
            CGImageGetColorSpace(self.CGImage),
            CGImageGetBitmapInfo(self.CGImage));

        CGContextConcatCTM(ctx, transform)

        if ( self.imageOrientation == UIImageOrientation.Left ||
            self.imageOrientation == UIImageOrientation.LeftMirrored ||
            self.imageOrientation == UIImageOrientation.Right ||
            self.imageOrientation == UIImageOrientation.RightMirrored ) {
                CGContextDrawImage(ctx, CGRectMake(0,0,self.size.height,self.size.width), self.CGImage)
        } else {
            CGContextDrawImage(ctx, CGRectMake(0,0,self.size.width,self.size.height), self.CGImage)
        }

        // And now we just create a new UIImage from the drawing context and return it
        return UIImage(CGImage: CGBitmapContextCreateImage(ctx))!
    }
}

Based on MetalHeart2003's earlier work..


f
fantaghirocco

Here is an UIImage extension in Swift 2 based on the accepted answer by @Anomie. It uses a clearer switch case. It also takes the optional value returned by CGBitmapContextCreateImage() into consideration.

extension UIImage {
    func rotateImageByOrientation() -> UIImage {
        // No-op if the orientation is already correct
        guard self.imageOrientation != .Up else {
            return self
        }

        // We need to calculate the proper transformation to make the image upright.
        // We do it in 2 steps: Rotate if Left/Right/Down, and then flip if Mirrored.
        var transform = CGAffineTransformIdentity;

        switch (self.imageOrientation) {
        case .Down, .DownMirrored:
            transform = CGAffineTransformTranslate(transform, self.size.width, self.size.height)
            transform = CGAffineTransformRotate(transform, CGFloat(M_PI))

        case .Left, .LeftMirrored:
            transform = CGAffineTransformTranslate(transform, self.size.width, 0)
            transform = CGAffineTransformRotate(transform, CGFloat(M_PI_2))

        case .Right, .RightMirrored:
            transform = CGAffineTransformTranslate(transform, 0, self.size.height)
            transform = CGAffineTransformRotate(transform, CGFloat(-M_PI_2))

        default:
            break
        }

        switch (self.imageOrientation) {
        case .UpMirrored, .DownMirrored:
            transform = CGAffineTransformTranslate(transform, self.size.width, 0)
            transform = CGAffineTransformScale(transform, -1, 1)

        case .LeftMirrored, .RightMirrored:
            transform = CGAffineTransformTranslate(transform, self.size.height, 0)
            transform = CGAffineTransformScale(transform, -1, 1)

        default:
            break
        }

        // Now we draw the underlying CGImage into a new context, applying the transform
        // calculated above.
        let ctx = CGBitmapContextCreate(nil, Int(self.size.width), Int(self.size.height),
            CGImageGetBitsPerComponent(self.CGImage), 0,
            CGImageGetColorSpace(self.CGImage),
            CGImageGetBitmapInfo(self.CGImage).rawValue)
        CGContextConcatCTM(ctx, transform)
        switch (self.imageOrientation) {
        case .Left, .LeftMirrored, .Right, .RightMirrored:
            CGContextDrawImage(ctx, CGRectMake(0,0,self.size.height,self.size.width), self.CGImage)

        default:
            CGContextDrawImage(ctx, CGRectMake(0,0,self.size.width,self.size.height), self.CGImage)
        }

        // And now we just create a new UIImage from the drawing context
        if let cgImage = CGBitmapContextCreateImage(ctx) {
            return UIImage(CGImage: cgImage)
        } else {
            return self
        }
    }
}

T
Teena nath Paul

I have experienced this issue with images taken from camera or saved in camera roll which are taken from camera. Images downloaded in photo library from safari browser does not rotate when uploaded.

I was able to solve this issue by making the image data as JPEG before uploading.

let image = info[UIImagePickerControllerOriginalImage] as! UIImage        
let data = UIImageJPEGRepresentation(image, 1.0)

We can now use the data for uploading and the image will not get rotated after upload.

Hope this will work.


So strange that the png data stays rotated, but that the rotation gets fixed when using jpeg data.
M
Meet Doshi

If I understand, what you want to do is disregard the orientation of the UIImage? If so then you could do this:-

//image is your original image
image = [UIImage imageWithCGImage:[image CGImage]
                             scale:[image scale]
                       orientation: UIImageOrientationUp];

or in Swift :-

image = UIImage(CGImage: image.CGImage!, scale: image.scale, orientation:.Up)

It solved my cropping issue.. Hope, this is what you're looking for..


F
Faisal

Swift 3 version based on @jake1981 who've taken it from @MetalHeart2003

extension UIImage {

    func fixOrientation() -> UIImage {

        // No-op if the orientation is already correct
        if ( self.imageOrientation == UIImageOrientation.up ) {
            return self;
        }

        // We need to calculate the proper transformation to make the image upright.
        // We do it in 2 steps: Rotate if Left/Right/Down, and then flip if Mirrored.

        var transform: CGAffineTransform = CGAffineTransform.identity

        if ( self.imageOrientation == UIImageOrientation.down || self.imageOrientation == UIImageOrientation.downMirrored ) {
            transform = transform.translatedBy(x: self.size.width, y: self.size.height)
            transform = transform.rotated(by: CGFloat(M_PI))
        }

        if ( self.imageOrientation == UIImageOrientation.left || self.imageOrientation == UIImageOrientation.leftMirrored ) {
            transform = transform.translatedBy(x: self.size.width, y: 0)
            transform = transform.rotated(by: CGFloat(M_PI_2))
        }

        if ( self.imageOrientation == UIImageOrientation.right || self.imageOrientation == UIImageOrientation.rightMirrored ) {
            transform = transform.translatedBy(x: 0, y: self.size.height);
            transform = transform.rotated(by: CGFloat(-M_PI_2));
        }

        if ( self.imageOrientation == UIImageOrientation.upMirrored || self.imageOrientation == UIImageOrientation.downMirrored ) {
            transform = transform.translatedBy(x: self.size.width, y: 0)
            transform = transform.scaledBy(x: -1, y: 1)
        }

        if ( self.imageOrientation == UIImageOrientation.leftMirrored || self.imageOrientation == UIImageOrientation.rightMirrored ) {
            transform = transform.translatedBy(x: self.size.height, y: 0);
            transform = transform.scaledBy(x: -1, y: 1);
        }

        // Now we draw the underlying CGImage into a new context, applying the transform
        // calculated above.
        let ctx: CGContext = CGContext(data: nil, width: Int(self.size.width), height: Int(self.size.height),
                                       bitsPerComponent: self.cgImage!.bitsPerComponent, bytesPerRow: 0,
                                       space: self.cgImage!.colorSpace!,
                                       bitmapInfo: self.cgImage!.bitmapInfo.rawValue)!
        ctx.concatenate(transform)

        if ( self.imageOrientation == UIImageOrientation.left ||
            self.imageOrientation == UIImageOrientation.leftMirrored ||
            self.imageOrientation == UIImageOrientation.right ||
            self.imageOrientation == UIImageOrientation.rightMirrored ) {

            ctx.draw(self.cgImage!, in: CGRect(x: 0, y: 0, width: self.size.height, height: self.size.width))
        } else {
            ctx.draw(self.cgImage!, in: CGRect(x: 0, y: 0, width: self.size.width, height: self.size.height))
        }

        // And now we just create a new UIImage from the drawing context and return it
        return UIImage(cgImage: ctx.makeImage()!)

    }
}

A
Alexey Malyarenko
@an0, thanks for the answer!
The only thing is autoreleasepool: 

func fixOrientation(img: UIImage) -> UIImage? {

    let result: UIImage?
    if img.imageOrientation == .up {
        result = img
    } else {

        result = autoreleasepool { () -> UIImage? in
            UIGraphicsBeginImageContextWithOptions(img.size, false, img.scale)
            let rect = CGRect(x: 0, y: 0, width: img.size.width, height: img.size.height)
            img.draw(in: rect)

            let normalizedImage = UIGraphicsGetImageFromCurrentImageContext()
            UIGraphicsEndImageContext()

            return normalizedImage
        }
    }

    return result
}

P
Prashanth Thota

Here is the Swift-4.2 code for automatic fix your image orientation Returns UIImage

func AutofixImageOrientation(_ image: UIImage)->UIImage {

    UIGraphicsBeginImageContext(image.size)

    image.draw(at: .zero)

    let newImage = UIGraphicsGetImageFromCurrentImageContext()

    UIGraphicsEndImageContext()

    return newImage ?? image
}

G
Gustavo Baiocchi Costa

I transposed this into Xamarin:

private static UIImage FixImageOrientation(UIImage image)
    {
        if (image.Orientation == UIImageOrientation.Up)
        {
            return image;
        }

        var transform = CGAffineTransform.MakeIdentity();

        float pi = (float)Math.PI;

        switch (image.Orientation)
        {
            case UIImageOrientation.Down:
            case UIImageOrientation.DownMirrored:
                transform = CGAffineTransform.Translate(transform, image.Size.Width, image.Size.Height);
                transform = CGAffineTransform.Rotate(transform, pi);
                break;

            case UIImageOrientation.Left:
            case UIImageOrientation.LeftMirrored:
                transform = CGAffineTransform.Translate(transform, image.Size.Width, 0);
                transform = CGAffineTransform.Rotate(transform, pi / 2);
                break;

            case UIImageOrientation.Right:
            case UIImageOrientation.RightMirrored:
                transform = CGAffineTransform.Translate(transform, 0, image.Size.Height);
                transform = CGAffineTransform.Rotate(transform, -(pi / 2));
                break;
        }

        switch (image.Orientation)
        {
            case UIImageOrientation.UpMirrored:
            case UIImageOrientation.DownMirrored:
                transform = CGAffineTransform.Translate(transform, image.Size.Width, 0);
                transform = CGAffineTransform.Scale(transform, -1, 1);
                break;

            case UIImageOrientation.LeftMirrored:
            case UIImageOrientation.RightMirrored:
                transform = CGAffineTransform.Translate(transform, image.Size.Height, 0);
                transform = CGAffineTransform.Scale(transform, -1, 1);
                break;
        }

        var ctx = new CGBitmapContext(null, (nint)image.Size.Width, (nint)image.Size.Height, image.CGImage.BitsPerComponent,
            image.CGImage.BytesPerRow, image.CGImage.ColorSpace, image.CGImage.BitmapInfo);

        ctx.ConcatCTM(transform);

        switch (image.Orientation)
        {
            case UIImageOrientation.Left:
            case UIImageOrientation.LeftMirrored:
            case UIImageOrientation.Right:
            case UIImageOrientation.RightMirrored:
                ctx.DrawImage(new CGRect(0, 0, image.Size.Height, image.Size.Width), image.CGImage);
                break;

            default:
                ctx.DrawImage(new CGRect(0, 0, image.Size.Width, image.Size.Height), image.CGImage);
                break;
        }

        var cgimg = ctx.ToImage();
        var img = new UIImage(cgimg);

        ctx.Dispose();
        ctx = null;
        cgimg.Dispose();
        cgimg = null;

        return img;
    }

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