How to rotate an image 90 degrees on iOS?

Question

What I want to do is take a snapshot from my camera , send it to a server and then the server sends me back the image on a viewController. If the image is in portrait mode t

Answer 1

It´s best only use the bitmap. In my case use a UIImage that is in reference.image and I converted image at base64String. Without CGAffineTransformMakeRotation and without rotatedViewBox.transform

var rotatedSize = reference.image.size;
                //Create bitmap context
                UIGraphicsBeginImageContext(rotatedSize);
                var bitmap = UIGraphicsGetCurrentContext();
                //move origin to the middle of the image for rotation
                CGContextTranslateCTM(bitmap, rotatedSize.width / 2, rotatedSize.height / 2);
                //rotate image context
                CGContextRotateCTM(bitmap, 1.5708);
                CGContextDrawImage(bitmap, CGRectMake(-reference.image.size.width / 2, -reference.image.size.height / 2, reference.image.size.width, reference.image.size.height), reference.image.CGImage);
                var rotatedImage = UIGraphicsGetImageFromCurrentImageContext();
                var base64Image = UIImageJPEGRepresentation(rotatedImage, compression).base64EncodedStringWithOptions(0);
                UIGraphicsEndImageContext();
                return base64Image;

Answer 2

Swift 4 | Xcode 9 syntax (please note that this code rotates a UIImageView 90 degrees clockwise, not a UIImage):

myImageView.transform = CGAffineTransform(rotationAngle: CGFloat(Double.pi / 2))