UIImage+Resize.m Fix for Rotation / Orientation on iOS 5

UIImage+Resize.m

- (UIImage *)resizedImage:(CGSize)newSize interpolationQuality:(CGInterpolationQuality)quality {
    BOOL drawTransposed;
    CGAffineTransform transform = CGAffineTransformIdentity;
    
    if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 5.0) {
        // Apprently in iOS 5 the image is already correctly rotated, so we don't need to rotate it manually
        drawTransposed = NO;  
    } else {    
        switch (self.imageOrientation) {
            case UIImageOrientationLeft:
            case UIImageOrientationLeftMirrored:
            case UIImageOrientationRight:
            case UIImageOrientationRightMirrored:
                drawTransposed = YES;
                break;
                
            default:
                drawTransposed = NO;
        }
        
        transform = [self transformForOrientation:newSize];
    } 
    
    return [self resizedImage:newSize
                    transform:transform
               drawTransposed:drawTransposed
         interpolationQuality:quality];
}

For better performance, make sure to store some global flag that you are running in iOS version >= 5.0 so that you would only check a boolean flag instead of casting a string to a float and checking its value.

Have you switched out the imageWithCGImage: method calls for imageWithCGImage:scale:orientation:?

Thanks for your suggestion. The scale parameter wouldn't let me scale it to whatever I wanted (not just scaled). I'm quite sure that imageWithCGImage:scale:orientation: does a similar thing underneath.