iOS - Rotating an image or picture

Question

My iOS app downloads some images from the internet and displays them on the screen (iPhone Portrait layout). Some of these images are more wider than taller, and in that case, when the image is presented to the screen, they appear squished (imagine the picture of a widescreen tv shrunk to iPhone's width). What I want to do is that everytime the width of the image is wider than the height of the image, I want to rotate the picture by 90 degrees clockwise (into landscape layout mode), save it on app's documents folder, and then present it on the screen - this way, the picture of the widescreen tv (e.g.) appears 90 degrees rotated but the image aspect ratio is not totally destroyed.

For various complicated reasons, I can't use landscape layout of my app - too many other side effects. So this is code I wrote:

UIImage *image = [[UIImage alloc] initWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:imageURL]]];

    CGFloat width = image.size.width;
    CGFloat height = image.size.height;

    if(width > 1.2*height) {
        NSLog(@"rotate the image");
        CGImageRef imageRef = [image CGImage];
        image = [UIImage imageWithCGImage:imageRef scale:1.0 orientation:UIImageOrientationLeft];
    }

Then I save the image into App's documents folder. Then a new UIViewController opens which reads the image file saved in the documents folder and then opens this image. Problem is, the image doesn't appear rotated at all - just appears the same way as the original - without any rotation. I do know that the above code tries to do what it is supposed to do because I do see NSLog "rotate the image" in the console. But somehow this image doesn't get saved as the rotated image.

So, how should I approach this issue?

EDIT: Code to save my image:

NSString *documentsDirectory = [NSHomeDirectory()        stringByAppendingPathComponent:@"Documents"];

    // Create image name
    NSString *path = [@"" stringByAppendingFormat:@"%@%@", @"image", @".png"];

    // Create full image path
    path = [documentsDirectory stringByAppendingPathComponent:path];

    path = [NSString stringWithFormat:@"%@", path];

    // Write image to image path
    NSData *data1 = [NSData dataWithData:UIImagePNGRepresentation(image)];
    [data1 writeToFile:path atomically:YES];

Can you add the code of the saving? also, what are you using the CGImageRef — La bla bla, Sep 13 '12 at 00:42
Some are doung like you, some are using the Context too [here][1] [1]: http://stackoverflow.com/questions/1315251/how-to-rotate-a-uiimage-90-degrees — , Sep 13 '12 at 00:45
I ran into a problem a while back similar to this, here's my SO post about it, maybe it'll help you double-check your solution? http://stackoverflow.com/questions/10600613/ios-image-orientation-has-strange-behavior — Boeckm, Oct 19 '12 at 17:24

score 1 · Accepted Answer · answered Sep 13 '12 at 03:18

1

The following website's solution ultimately worked for me:

http://www.catamount.com/blog/uiimage-extensions-for-cutting-scaling-and-rotating-uiimages/

answered Sep 13 '12 at 03:18

BlueChips23

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iOS - Rotating an image or picture

1 Answers1