iOS - UIImageView - how to handle UIImage image orientation

Question

Is it possible to setup UIImageView to handle image orientation  When I set the UIImageView to image with orientation RIGHT  it is photo from camera roll   the image is rotated to right  but I want to show it in proper orientation  as it was taken   I know I can rotate image data but it is possible to do it more elegant

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Swift 3 1  func fixImageOrientation   image  UIImage - gt UIImage       UIGraphicsBeginImageContext image size      image draw at   zero      let newImage   UIGraphicsGetImageFromCurrentImageContext       UIGraphicsEndImageContext       return newImage    image

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here is a workable sample cod  considering the image orientation    define rad angle    angle    180 0   M PI  -  CGAffineTransform orientationTransformedRectOfImage  UIImage   img       CGAffineTransform rectTransform      switch  img imageOrientation                case UIImageOrientationLeft              rectTransform   CGAffineTransformTranslate CGAffineTransformMakeRotation rad 90    0  -img size height               break          case UIImageOrientationRight              rectTransform   CGAffineTransformTranslate CGAffineTransformMakeRotation rad -90    -img size width  0               break          case UIImageOrientationDown              rectTransform   CGAffineTransformTranslate CGAffineTransformMakeRotation rad -180    -img size width  -img size height               break          default              rectTransform   CGAffineTransformIdentity              return CGAffineTransformScale rectTransform  img scale  img scale       -  UIImage   croppedImage  UIImage  orignialImage InRect  CGRect visibleRect        transform visible rect to image orientation     CGAffineTransform rectTransform    self orientationTransformedRectOfImage orignialImage       visibleRect   CGRectApplyAffineTransform visibleRect  rectTransform          crop image     CGImageRef imageRef   CGImageCreateWithImageInRect  orignialImage CGImage   visibleRect       UIImage  result    UIImage imageWithCGImage imageRef scale orignialImage scale orientation orignialImage imageOrientation       CGImageRelease imageRef       return result

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This method first checks the current orientation of UIImage and then it changes the orientation in a clockwise way and return UIImage You can show this image as     self imageView image   rotateImage currentUIImage       func rotateImage image UIImage - gt UIImage               var rotatedImage   UIImage            switch image imageOrientation                       case UIImageOrientation Right              rotatedImage   UIImage CGImage image CGImage   scale  1  orientation UIImageOrientation Down               case UIImageOrientation Down              rotatedImage   UIImage CGImage image CGImage   scale  1  orientation UIImageOrientation Left                case UIImageOrientation Left              rotatedImage   UIImage CGImage image CGImage   scale  1  orientation UIImageOrientation Up                 default              rotatedImage   UIImage CGImage image CGImage   scale  1  orientation UIImageOrientation Right                     return rotatedImage          Swift 4 version  func rotateImage image UIImage  - gt  UIImage               var rotatedImage   UIImage           switch image imageOrientation                   case  right              rotatedImage   UIImage cgImage  image cgImage   scale  1 0  orientation   down           case  down              rotatedImage   UIImage cgImage  image cgImage   scale  1 0  orientation   left           case  left              rotatedImage   UIImage cgImage  image cgImage   scale  1 0  orientation   up           default              rotatedImage   UIImage cgImage  image cgImage   scale  1 0  orientation   right                     return rotatedImage

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You can completely avoid manually doing the transforms and scaling yourself  as suggested by an0 in this answer here   -  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      The documentation for the UIImage methods size and drawInRect explicitly states that they take into account orientation

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If you need to rotate and fix the image orientation below extension would be useful   extension UIImage        public func imageRotatedByDegrees degrees  CGFloat  - gt  UIImage             Calculate the size of the rotated view s containing box for our drawing space         let rotatedViewBox  UIView   UIView frame  CGRect x  0  y  0  width  self size width  height  self size height           let t  CGAffineTransform   CGAffineTransform rotationAngle  degrees   CGFloat pi   180          rotatedViewBox transform   t         let rotatedSize  CGSize   rotatedViewBox frame size           Create the bitmap context         UIGraphicsBeginImageContext rotatedSize          let bitmap  CGContext   UIGraphicsGetCurrentContext              Move the origin to the middle of the image so we will rotate and scale around the center          bitmap translateBy x  rotatedSize width   2  y  rotatedSize height   2            Rotate the image context         bitmap rotate by   degrees   CGFloat pi   180             Now  draw the rotated scaled image into the context         bitmap scaleBy x  1 0  y  -1 0          bitmap draw self cgImage   in  CGRect x  -self size width   2  y  -self size height   2  width  self size width  height  self size height           let newImage  UIImage   UIGraphicsGetImageFromCurrentImageContext            UIGraphicsEndImageContext           return newImage             public func fixedOrientation   - gt  UIImage           if imageOrientation    UIImageOrientation up               return self                    var transform  CGAffineTransform   CGAffineTransform identity          switch imageOrientation           case UIImageOrientation down  UIImageOrientation downMirrored              transform   transform translatedBy x  size width  y  size height              transform   transform rotated by  CGFloat pi              break         case UIImageOrientation left  UIImageOrientation leftMirrored              transform   transform translatedBy x  size width  y  0              transform   transform rotated by  CGFloat pi 2              break         case UIImageOrientation right  UIImageOrientation rightMirrored              transform   transform translatedBy x  0  y  size height              transform   transform rotated by  -CGFloat pi 2              break         case UIImageOrientation up  UIImageOrientation upMirrored              break                    switch imageOrientation           case UIImageOrientation upMirrored  UIImageOrientation downMirrored              transform translatedBy x  size width  y  0              transform scaledBy x  -1  y  1              break         case UIImageOrientation leftMirrored  UIImageOrientation rightMirrored              transform translatedBy x  size height  y  0              transform scaledBy x  -1  y  1          case UIImageOrientation up  UIImageOrientation down  UIImageOrientation left  UIImageOrientation right              break                    let ctx  CGContext   CGContext data  nil                                         width  Int size width                                          height  Int size height                                          bitsPerComponent  self cgImage  bitsPerComponent                                         bytesPerRow  0                                         space  self cgImage  colorSpace                                          bitmapInfo  CGImageAlphaInfo premultipliedLast rawValue            ctx concatenate transform           switch imageOrientation           case UIImageOrientation left  UIImageOrientation leftMirrored  UIImageOrientation right  UIImageOrientation rightMirrored              ctx draw self cgImage   in  CGRect x  0  y  0  width  size height  height  size width           default              ctx draw self cgImage   in  CGRect x  0  y  0  width  size width  height  size height               break                    let cgImage  CGImage   ctx makeImage             return UIImage cgImage  cgImage

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Inspired from  Aqua Answer       in Objective C  -  UIImage   fixImageOrientation  UIImage   img       UIGraphicsBeginImageContext img size       img drawAtPoint CGPointZero       UIImage  newImg   UIGraphicsGetImageFromCurrentImageContext       UIGraphicsEndImageContext        if  newImg           return newImg           return img

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Thanks to Waseem05 for his Swift 3 translation but his method only worked for me when I wrapped it inside an extension to UIImage and placed it outside below the parent class like so   extension UIImage            func fixOrientation   - gt  UIImage                        if self imageOrientation    UIImageOrientation up               return self                    var transform   CGAffineTransform identity          switch self imageOrientation           case  down   downMirrored              transform   transform translatedBy x  self size width  y  self size height              transform   transform rotated by  CGFloat M PI             case  left   leftMirrored              transform   transform translatedBy x  self size width  y  0               transform   transform rotated by  CGFloat M PI 2             case  right   rightMirrored              transform   transform translatedBy x  0  y  self size height               transform   transform rotated by  CGFloat -M PI 2             case  up   upMirrored              break                     switch self imageOrientation            case  upMirrored   downMirrored              transform   transform translatedBy x  self size width  y  0              transform   transform scaledBy x  -1  y  1           case  leftMirrored   rightMirrored              transform   transform translatedBy x  self size height  y  0              transform   transform scaledBy x  -1  y  1            default              break                        Now we draw the underlying CGImage into a new context  applying the transform            calculated above          let ctx   CGContext              data  nil              width  Int self size width               height  Int self size height               bitsPerComponent  self cgImage  bitsPerComponent              bytesPerRow  0              space  self cgImage  colorSpace               bitmapInfo  UInt32 self cgImage  bitmapInfo rawValue                       ctx  concatenate transform            switch self imageOrientation            case  left   leftMirrored   right   rightMirrored                 Grr                ctx  draw self cgImage   in  CGRect x 0  y  0  width  self size height  height self size width            default              ctx  draw self cgImage   in  CGRect x 0  y  0  width  self size width  height self size height               break                        And now we just create a new UIImage from the drawing context         let cgimg   ctx  makeImage            let img   UIImage cgImage  cgimg            return img             Then called it with   let correctedImage UIImage   wonkyImage fixOrientation     And all was then well   Apple should make it easier to discard orientation when we don t need front back camera and up down left right device orientation metadata

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I converted the code in Anomie s answer here  copy-pasted above by suvish valsan  into Swift   func fixOrientation   - gt  UIImage       if self imageOrientation    UIImageOrientation Up           return self            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         case  Up   UpMirrored          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           UInt32 CGImageGetBitmapInfo self CGImage  rawValue             CGContextConcatCTM ctx  transform        switch self imageOrientation       case  Left   LeftMirrored   Right   RightMirrored             Grr            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           break                And now we just create a new UIImage from the drawing context     let cgimg   CGBitmapContextCreateImage ctx       let img   UIImage CGImage  cgimg        return img       I replaced all occurencies of the parameter image with self  because my code is an extension on UIImage      EDIT  Swift 3 version   The method returns an optional  because many of the intermediate calls can fail and I don t like to use     func fixOrientation   - gt  UIImage         guard let cgImage   self cgImage else           return nil            if self imageOrientation    UIImageOrientation up           return self            let width    self size width     let height   self size height      var transform   CGAffineTransform identity      switch self imageOrientation       case  down   downMirrored          transform   transform translatedBy x  width  y  height          transform   transform rotated by  CGFloat pi       case  left   leftMirrored          transform   transform translatedBy x  width  y  0          transform   transform rotated by  0 5 CGFloat pi       case  right   rightMirrored          transform   transform translatedBy x  0  y  height          transform   transform rotated by  -0 5 CGFloat pi       case  up   upMirrored          break            switch self imageOrientation       case  upMirrored   downMirrored          transform   transform translatedBy x  width  y  0          transform   transform scaledBy x  -1  y  1       case  leftMirrored   rightMirrored          transform   transform translatedBy x  height  y  0          transform   transform scaledBy x  -1  y  1       default          break                Now we draw the underlying CGImage into a new context  applying the transform        calculated above      guard let colorSpace   cgImage colorSpace else           return nil            guard let context   CGContext          data  nil          width  Int width           height  Int height           bitsPerComponent  cgImage bitsPerComponent          bytesPerRow  0          space  colorSpace          bitmapInfo  UInt32 cgImage bitmapInfo rawValue            else               return nil            context concatenate transform        switch self imageOrientation        case  left   leftMirrored   right   rightMirrored             Grr            context draw cgImage  in  CGRect x  0  y  0  width  height  height  width        default          context draw cgImage  in  CGRect x  0  y  0  width  width  height  height                 And now we just create a new UIImage from the drawing context     guard let newCGImg   context makeImage   else           return nil            let img   UIImage cgImage  newCGImg       return img       Note  Swift 3 version odes compile under Xcode 8 1  but haven t tested it actually works  There might be a typo somewhere  mixed up width height  etc  Feel free to point fix any errors

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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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I converted the code from  Nicolas Miari answer to Swift 3 in case anybody needs it  func fixOrientation   - gt  UIImage        if self imageOrientation    UIImageOrientation up           return self            var transform   CGAffineTransform identity      switch self imageOrientation       case  down   downMirrored          transform   transform translatedBy x  self size width  y  self size height          transform   transform rotated by  CGFloat M PI         case  left   leftMirrored          transform   transform translatedBy x  self size width  y  0           transform   transform rotated by  CGFloat M PI 2         case  right   rightMirrored          transform   transform translatedBy x  0  y  self size height           transform   transform rotated by  CGFloat -M PI 2         case  up   upMirrored          break             switch self imageOrientation        case  upMirrored   downMirrored          transform   transform translatedBy x  self size width  y  0          transform   transform scaledBy x  -1  y  1       case  leftMirrored   rightMirrored          transform   transform translatedBy x  self size height  y  0          transform   transform scaledBy x  -1  y  1        default          break                Now we draw the underlying CGImage into a new context  applying the transform        calculated above      let ctx   CGContext          data  nil          width  Int self size width           height  Int self size height           bitsPerComponent  self cgImage  bitsPerComponent          bytesPerRow  0          space  self cgImage  colorSpace           bitmapInfo  UInt32 self cgImage  bitmapInfo rawValue               ctx  concatenate transform        switch self imageOrientation        case  left   leftMirrored   right   rightMirrored             Grr            ctx  draw self cgImage   in  CGRect x 0  y  0  width  self size height  height self size width        default          ctx  draw self cgImage   in  CGRect x 0  y  0  width  self size width  height self size height           break                And now we just create a new UIImage from the drawing context     let cgimg   ctx  makeImage        let img   UIImage cgImage  cgimg        return img

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extension UIImage       func fixImageOrientation   - gt  UIImage           UIGraphicsBeginImageContext self size          self draw at   zero          let newImage   UIGraphicsGetImageFromCurrentImageContext           UIGraphicsEndImageContext           return newImage    self            Create extension like top example  Call it  imageView image  fixImageOrientation   or UIImage named   someImage   fixImageOrientation   Good luck all

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UIImage extension in Swift  You don t need to do all that flipping at all  really  Objective-C original is here  but I ve added the bit that respects the alpha of the original image  crudely  but it works to differentiate opaque images from transparent images       from https   github com mbcharbonneau UIImage-Categories blob master UIImage 2BAlpha m    Returns true if the image has an alpha layer     private func hasAlpha   - gt  Bool           guard let cg   self cgImage else   return false           let alpha   cg alphaInfo         let retVal    alpha     first    alpha     last    alpha     premultipliedFirst    alpha     premultipliedLast          return retVal            func normalizedImage   - gt  UIImage            if self imageOrientation     up               return self                   UIGraphicsBeginImageContextWithOptions self size   self hasAlpha    self scale          var rect   CGRect zero         rect size   self size         self draw in  rect          let retVal   UIGraphicsGetImageFromCurrentImageContext           UIGraphicsEndImageContext           return retVal

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Swift 3 0 version of Tommy s answer  let imageToDisplay   UIImage init cgImage  originalImage cgImage   scale  originalImage scale  orientation  UIImageOrientation up

[ios] iOS - UIImageView - how to handle UIImage image orientation

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