iOS UIImage uploaded to server are rotated [duplicate] - ios

Question

This question already has answers here:
iOS UIImagePickerController result image orientation after upload
(20 answers)
Closed 9 years ago.
I'm using the following code to send an image to a web server. It works, the problem is that the images are rotated for some reason when they get uploaded.
here's my upload method:
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
[self dismissViewControllerAnimated:YES completion:nil];
NSData *image = UIImageJPEGRepresentation([info objectForKey:UIImagePickerControllerOriginalImage], 0.1);
// use token with url for json data from contents of url
NSString *savedValue = [[NSUserDefaults standardUserDefaults]
stringForKey:#"token"];
NSString *urlString = [NSString stringWithFormat:#"%#%#/photos?token=%#", kIDURLPhoto, listingId, savedValue];
NSLog(#"urlstring for comment is %#",urlString);
self.flUploadEngine = [[fileUploadEngine alloc] initWithHostName:urlString customHeaderFields:nil];
NSMutableDictionary *postParams = [NSMutableDictionary dictionaryWithObjectsAndKeys: #"image", #"caption", nil];
self.flOperation = [self.flUploadEngine postDataToServer:postParams path:nil];
[self.flOperation addData:image forKey:#"picture" mimeType:#"image/jpeg" fileName:#"upload.jpg"];
[self.flOperation addCompletionHandler:^(MKNetworkOperation* operation) {
NSLog(#"%#", [operation responseString]);
// handle a successful 200 response
[self.flUploadEngine enqueueOperation:self.flOperation];
// for iOS7
if ([self respondsToSelector:#selector(setNeedsStatusBarAppearanceUpdate)]) {
[[UIApplication sharedApplication] setStatusBarHidden:YES];
}
[self forceReload];
}

Answer 1

Swift 5 Extension:
extension UIImage {
/// Fix image orientaton to protrait up
func fixedOrientation() -> UIImage? {
guard imageOrientation != UIImage.Orientation.up else {
// This is default orientation, don't need to do anything
return self.copy() as? UIImage
}
guard let cgImage = self.cgImage else {
// CGImage is not available
return nil
}
guard let colorSpace = cgImage.colorSpace, let ctx = CGContext(data: nil, width: Int(size.width), height: Int(size.height), bitsPerComponent: cgImage.bitsPerComponent, bytesPerRow: 0, space: colorSpace, bitmapInfo: CGImageAlphaInfo.premultipliedLast.rawValue) else {
return nil // Not able to create CGContext
}
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 / 2.0)
case .right, .rightMirrored:
transform = transform.translatedBy(x: 0, y: size.height)
transform = transform.rotated(by: CGFloat.pi / -2.0)
case .up, .upMirrored:
break
#unknown default:
fatalError("Missing...")
break
}
// Flip image one more time if needed to, this is to prevent flipped image
switch imageOrientation {
case .upMirrored, .downMirrored:
transform = transform.translatedBy(x: size.width, y: 0)
transform = transform.scaledBy(x: -1, y: 1)
case .leftMirrored, .rightMirrored:
transform = transform.translatedBy(x: size.height, y: 0)
transform = transform.scaledBy(x: -1, y: 1)
case .up, .down, .left, .right:
break
#unknown default:
fatalError("Missing...")
break
}
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))
break
}
guard let newCGImage = ctx.makeImage() else { return nil }
return UIImage.init(cgImage: newCGImage, scale: 1, orientation: .up)
}
}
Objective C Code :
-(UIImage *)scaleAndRotateImage:(UIImage *)image{
// No-op if the orientation is already correct
if (image.imageOrientation == UIImageOrientationUp) return image;
// 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 (image.imageOrientation) {
case UIImageOrientationDown:
case UIImageOrientationDownMirrored:
transform = CGAffineTransformTranslate(transform, image.size.width, image.size.height);
transform = CGAffineTransformRotate(transform, M_PI);
break;
case UIImageOrientationLeft:
case UIImageOrientationLeftMirrored:
transform = CGAffineTransformTranslate(transform, image.size.width, 0);
transform = CGAffineTransformRotate(transform, M_PI_2);
break;
case UIImageOrientationRight:
case UIImageOrientationRightMirrored:
transform = CGAffineTransformTranslate(transform, 0, image.size.height);
transform = CGAffineTransformRotate(transform, -M_PI_2);
break;
case UIImageOrientationUp:
case UIImageOrientationUpMirrored:
break;
}
switch (image.imageOrientation) {
case UIImageOrientationUpMirrored:
case UIImageOrientationDownMirrored:
transform = CGAffineTransformTranslate(transform, image.size.width, 0);
transform = CGAffineTransformScale(transform, -1, 1);
break;
case UIImageOrientationLeftMirrored:
case UIImageOrientationRightMirrored:
transform = CGAffineTransformTranslate(transform, image.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, image.size.width, image.size.height,
CGImageGetBitsPerComponent(image.CGImage), 0,
CGImageGetColorSpace(image.CGImage),
CGImageGetBitmapInfo(image.CGImage));
CGContextConcatCTM(ctx, transform);
switch (image.imageOrientation) {
case UIImageOrientationLeft:
case UIImageOrientationLeftMirrored:
case UIImageOrientationRight:
case UIImageOrientationRightMirrored:
// Grr...
CGContextDrawImage(ctx, CGRectMake(0,0,image.size.height,image.size.width), image.CGImage);
break;
default:
CGContextDrawImage(ctx, CGRectMake(0,0,image.size.width,image.size.height), image.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;
}
Use of code
UIImage *img=[info objectForKey:UIImagePickerControllerOriginalImage];
img=[self scaleAndRotateImage:img];
NSData *image = UIImageJPEGRepresentation(img, 0.1);

Answer 2

Most probably you are not taking into account exif data, they give the rotation of the camera and you should add them to the image EXIF dictionary. In this way when you open the image the reading software can rotate the image accordingly. Check this question and relative answers, it would be helpful