After Getting Image from Uiimagepickercontroller, Uiimageview Rotates Image for iPhone 5

iOS UIImagePickerController result image orientation after upload

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

Selecting images with UIImagePickerController() auto-rotates them

Created an UIImage extension to keep the image in the original position,

extension UIImage {
    func fixedOrientation() -> UIImage {

        if imageOrientation == .up {
            return self
        }

        var transform: CGAffineTransform = CGAffineTransform.identity

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

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

        if let cgImage = self.cgImage, let colorSpace = cgImage.colorSpace,
            let ctx: CGContext = CGContext(data: nil, width: Int(size.width), height: Int(size.height), bitsPerComponent: cgImage.bitsPerComponent, bytesPerRow: 0, space: colorSpace, bitmapInfo: CGImageAlphaInfo.premultipliedLast.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))
            }
            if let ctxImage: CGImage = ctx.makeImage() {
                return UIImage(cgImage: ctxImage)
            } else {
                return self
            }
        } else {
            return self
        }
    }
}

To use the extension's method, please should do the following with your image,

let orientedImage = image?.fixedOrientation()

In your case, inside func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) method,

...
guard let image = info[.originalImage] as? UIImage else {
        return
    }
let orientedImage = image.fixedOrientation()
if let imageData = orientedImage.pngData() {
...

UIImagePNGRepresentation issues? / Images rotated by 90 degrees

I had the same problem and just figured out the reason: starting with iOS 4.0 when the camera takes a photo it does not rotate it before saving, it simply sets a rotation flag in the EXIF data of the JPEG.

If you save a UIImage as a JPEG, it will set the rotation flag.

PNGs do not support a rotation flag, so if you save a UIImage as a PNG, it will be rotated incorrectly and not have a flag set to fix it. So if you want PNGs you must rotate them yourself.

I would call this a bug in the PNG saving function but that's just an opinion (they should at least warn you about this).

iOS - UIImageView - how to handle UIImage image orientation

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

UIImage *originalImage = [... whatever ...];

UIImage *imageToDisplay =
     [UIImage imageWithCGImage:[originalImage CGImage]
              scale:[originalImage scale]
              orientation: UIImageOrientationUp];

So you're creating a new UIImage with the same pixel data as the original (referenced via its CGImage property) but you're specifying an orientation that doesn't rotate the data.

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