iOS UIImagePickerController result image orientation after upload

Question

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.

Answer 1

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

Answer 2

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.

Answer 3

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
}

Answer 4

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)
    }

Answer 5

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
        }
    }
}