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[mmd30]

I am using the UIImagePickerController to capture a picture from the camera. I then scale and rotate the image using code that I has been posted repeatedly on various SDK forums. The problem appears that the UIImage returned to the UIImagePickerController's delegate is reporting the wrong orientation. Has anyone seen this issue before and if so, do you have any suggestions or solutions?

Here is the delegate's method to get the returned image. The UIImage passed into this method does not have the correct orientation.

- (void) imagePickerController:(UIImagePickerController *) picker
     didFinishPickingImage:(UIImage *) image
     editingInfo:(NSDictionary *) editingInfo

     {
selectedImage = [self scaleAndRotateImage:image];
selectedImageView.image = selectedImage;

}

Here is the scale and rotate code that I mentioned from numerous other posts.

- (UIImage *)scaleAndRotateImage:(UIImage *)image

{

     int kMaxResolution = 480; 


     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 = bounds.size.width / ratio;
          }
          else {
               bounds.size.height = kMaxResolution;
               bounds.size.width = 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 :NSInternalInconsistencyExceptionformat:@"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;
}