UIImagePickerController camera preview is portrait in landscape app

Question

In my landscape-only iPhone application, I launch a UIImagePickerController to take a photo, but the live image displayed from the camera is in portrait orientation, with blank space around it. The image is rotated.

Once the camera button is pressed, the preview is very messy, with most of the preview off screen, and views not correctly aligned.

Apple has acknowledged that this is defect, and is working on it.

My question is, does anyone have a work-around (legal or illegal) that would allow me to get this working now. I wouldn't release to the App Store with an illegal fix, but I would have a much better app for user testing - currently the camera is pretty much unusable in landscape.

I will attach a simple test project and images if I can.

Edit - just to clarify, the image I get is correctly landscape. I want the camera & preview UIs to look right!

Answer 1

The answer is more ridiculous than you might think. I had the same problem and found a solution in a forum somewhere. Pass your taken image into a method like this:

// Code from: http://discussions.apple.com/thread.jspa?messageID=7949889
- (UIImage *)scaleAndRotateImage:(UIImage *)image {
  int kMaxResolution = 640; // Or whatever

    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 = roundf(bounds.size.width / ratio);
        }
        else {
            bounds.size.height = kMaxResolution;
            bounds.size.width = roundf(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:NSInternalInconsistencyException format:@"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;
}

:(

Answer 2

I'm unable to get that code to work. I get various invalid context errors:

Error: CGContextScaleCTM: invalid context

Error: CGContextTranslateCTM: invalid context

Error: CGContextConcatCTM: invalid context

Error: CGContextDrawImage: invalid context

Answer 3

Even I am getting these errors Error: CGContextScaleCTM: invalid context

Error: CGContextTranslateCTM: invalid context

Error: CGContextConcatCTM: invalid context

Error: CGContextDrawImage: invalid context

Answer 4

I am taking a screen shot in my app and I used a variation of Squeegy's answer to handle my landscape right issue showing incorrectly. My app is always landscape right and I didn't have a landscape left example. This will return a landscape right screen shot correctly. I have not tried landscape left.

The problem for my app is that a screen shot always has an imageOrientation of UIImageOrientationUp. Therefore it is up to me to know what the orientation was and change it appropriately.

I hope this helps with your scenario. If this works on landscape left or you get a variation that works on landscape left please post it.

        // Code from: http://discussions.apple.com/thread.jspa?messageID=7949889
    //variation of Squeegy's answer here. Resolves landscape right for my screenshot
        - (UIImage *)scaleAndRotateImage:(UIImage *)image {
            int kMaxResolution = 640; // Or whatever


        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 = roundf(bounds.size.width / ratio);
            }
            else {
                bounds.size.height = kMaxResolution;
                bounds.size.width = roundf(bounds.size.height * ratio);
            }
        }

        CGFloat scaleRatio = bounds.size.width / width;
        CGSize imageSize = CGSizeMake(CGImageGetWidth(imgRef), CGImageGetHeight(imgRef));
        CGFloat boundHeight;

        boundHeight = bounds.size.height;
        bounds.size.height = bounds.size.width;
        bounds.size.width = boundHeight;
        transform = CGAffineTransformMakeTranslation(imageSize.height, imageSize.width/2.0);
        transform = CGAffineTransformRotate(transform, M_PI / 2.0);

        UIGraphicsBeginImageContext(bounds.size);

        CGContextRef context = UIGraphicsGetCurrentContext();

UIImageOrientation orient = image.imageOrientation;

        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;
    }