Cropping UIImage in any image resolution

Question

Possible Duplicate:
Cropping a UIImage

I saw many tutorials about cropping images and am trying my luck but with no success.

I need to crop the image from AVFoundation. Since when the image is being taken from the camera it is rotated left from Portrait mode, I also need to rotate it right and my x and y are opposite. The problem is that if I send the frame of the image where I would it to reside, it seems to me that there is no correlation in the size of the image and the rectangle.

The code is:

@property (weak, nonatomic) IBOutlet UIView *videoPreviewView;
...
...
int width = videoPreviewView.frame.size.width;
int height = videoPreviewView.frame.size.height;
int x = videoPreviewView.frame.origin.x;
int y = videoPreviewView.frame.origin.y;
CGRect croprect = CGRectMake(y, x,height,width);
// Draw new image in current graphics context
CGImageRef imageRef = CGImageCreateWithImageInRect([sourceImage CGImage], croprect);
// Create new cropped UIImage
UIImage *resultImage = [UIImage imageWithCGImage:imageRef scale:[sourceImage scale] orientation:UIImageOrientationRight];

When I print the size of the frame I get:

(4.5,69.5,310,310)

and the image size is:

(720,1280)

How can I perform cropping in any image resolution?

I tried multiplying the values with image.scale - however, the value is 1.00

Refer this http://stackoverflow.com/questions/158914/cropping-a-uiimage — Arun, Feb 04 '13 at 08:48
@Spynet I tried the code. It doesn't crop my image which is high resolution — Dejell, Feb 04 '13 at 08:49

score 1 · Accepted Answer · answered Feb 04 '13 at 05:50

1

Try this one.This will definitely help you out. https://github.com/barrettj/BJImageCropper

answered Feb 04 '13 at 05:50

kumareshm174

304
1
11

Can you edit your post with the advantage of using the above library? – Dejell Feb 04 '13 at 08:14
@Odelya A sample project is already provided along with the library in the link that i sent. – kumareshm174 Feb 04 '13 at 09:35
I saw the method calcFrameWithImage - it seems to me something that could help but not sure exactly how. Do you refer to it? Maybe you want to post the relevant code? – Dejell Feb 04 '13 at 11:07

Vedchi · Answer 2 · 2013-04-09T06:46:12.457

To resize image, Try this    

    UIImage *image = [UIImage imageNamed:@"image.png"];

    CGSize itemSize = CGSizeMake((your Width), (your Height));
    UIGraphicsBeginImageContext(itemSize);
    CGRect imageRect = CGRectMake(0.0, 0.0, itemSize.width, itemSize.height);
    [image drawInRect:imageRect];

    UIImage * yourCroppedImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

To Crop,

    // Create new image context
    UIGraphicsBeginImageContext(SIZE);

    // Create CGRect for image
    CGRect newRect = CGRectMake(x, y,SIZE.width,SIZE.height);

    // Draw the image into the rect
    [ORIGINALIMAGE drawInRect:newRect];

    // Saving the image, ending image context
    UIImage * newImage = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

This resizes it but doesn't crop it! If I try to set CGRectMake(x,y,itemSize.width,itemSize.height) I get a blank white area — Dejell, Feb 04 '13 at 07:47

Cropping UIImage in any image resolution

2 Answers2