Rounded Corners on UIImage

I'm trying to draw images on the iPhone using with rounded corners, a la the contact images in the Contacts app. I've got code that generally work, but it occasionally crashes inside of the UIImage drawing routines with an EXEC_BAD_ACCESS - KERN_INVALID_ADDRESS. I thought this might be related to the cropping question I asked a few weeks back, but I believe I'm setting up the clipping path correctly.

Here's the code I'm using - when it doesn't crash, the result looks fine and anybody looking to get a similar look is free to borrow the code.

- (UIImage *)borderedImageWithRect: (CGRect)dstRect radius:(CGFloat)radius {
    UIImage *maskedImage = nil;

    radius = MIN(radius, .5 * MIN(CGRectGetWidth(dstRect), CGRectGetHeight(dstRect)));
    CGRect interiorRect = CGRectInset(dstRect, radius, radius);

    UIGraphicsBeginImageContext(dstRect.size);
    CGContextRef maskedContextRef = UIGraphicsGetCurrentContext();
    CGContextSaveGState(maskedContextRef);

    CGMutablePathRef borderPath = CGPathCreateMutable();
    CGPathAddArc(borderPath, NULL, CGRectGetMinX(interiorRect), CGRectGetMinY(interiorRect), radius, PNDegreeToRadian(180), PNDegreeToRadian(270), NO);
    CGPathAddArc(borderPath, NULL, CGRectGetMaxX(interiorRect), CGRectGetMinY(interiorRect), radius, PNDegreeToRadian(270.0), PNDegreeToRadian(360.0), NO);
    CGPathAddArc(borderPath, NULL, CGRectGetMaxX(interiorRect), CGRectGetMaxY(interiorRect), radius, PNDegreeToRadian(0.0), PNDegreeToRadian(90.0), NO);
    CGPathAddArc(borderPath, NULL, CGRectGetMinX(interiorRect), CGRectGetMaxY(interiorRect), radius, PNDegreeToRadian(90.0), PNDegreeToRadian(180.0), NO);

    CGContextBeginPath(maskedContextRef);
    CGContextAddPath(maskedContextRef, borderPath);
    CGContextClosePath(maskedContextRef);
    CGContextClip(maskedContextRef);

    [self drawInRect: dstRect];

    maskedImage = UIGraphicsGetImageFromCurrentImageContext();
    CGContextRestoreGState(maskedContextRef);
    UIGraphicsEndImageContext();

    return maskedImage;
}

and here's the crash log. It looks the same whenever I get one of these crashes

Exception Type:  EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0x6e2e6181
Crashed Thread:  0

Thread 0 Crashed:
0   com.apple.CoreGraphics          0x30fe56d8 CGGStateGetRenderingIntent + 4
1   libRIP.A.dylib                  0x33c4a7d8 ripc_RenderImage + 104
2   libRIP.A.dylib                  0x33c51868 ripc_DrawImage + 3860
3   com.apple.CoreGraphics          0x30fecad4 CGContextDelegateDrawImage + 80
4   com.apple.CoreGraphics          0x30feca40 CGContextDrawImage + 368
5   UIKit                           0x30a6a708 -[UIImage drawInRect:blendMode:alpha:] + 1460
6   UIKit                           0x30a66904 -[UIImage drawInRect:] + 72
7   MyApp                           0x0003f8a8 -[UIImage(PNAdditions) borderedImageWithRect:radius:] (UIImage+PNAdditions.m:187)

Here is an even easier method that is available in iPhone 3.0 and up. Every View-based object has an associated layer. Each layer can have a corner radius set, this will give you just what you want:

UIImageView * roundedView = [[UIImageView alloc] initWithImage: [UIImage imageNamed:@"wood.jpg"]];
// Get the Layer of any view
CALayer * l = [roundedView layer];
[l setMasksToBounds:YES];
[l setCornerRadius:10.0];

// You can even add a border
[l setBorderWidth:4.0];
[l setBorderColor:[[UIColor blueColor] CGColor]];

I'm gonna go ahead here and actually answer the question in the title.

Try this category.

UIImage+additions.h

#import <UIKit/UIKit.h>

@interface UIImage (additions)
-(UIImage*)makeRoundCornersWithRadius:(const CGFloat)RADIUS;
@end

UIImage+additions.m

#import "UIImage+additions.h"

@implementation UIImage (additions)
-(UIImage*)makeRoundCornersWithRadius:(const CGFloat)RADIUS {
    UIImage *image = self;

    // Begin a new image that will be the new image with the rounded corners
    // (here with the size of an UIImageView)
    UIGraphicsBeginImageContextWithOptions(image.size, NO, image.scale);

    const CGRect RECT = CGRectMake(0, 0, image.size.width, image.size.height);
    // Add a clip before drawing anything, in the shape of an rounded rect
    [[UIBezierPath bezierPathWithRoundedRect:RECT cornerRadius:RADIUS] addClip];
    // Draw your image
    [image drawInRect:RECT];

    // Get the image, here setting the UIImageView image
    //imageView.image
    UIImage* imageNew = UIGraphicsGetImageFromCurrentImageContext();

    // Lets forget about that we were drawing
    UIGraphicsEndImageContext();

    return imageNew;
}
@end

If appIconImage is an UIImageView, then:

appIconImage.image = [UIImage imageWithContentsOfFile:@"image.png"]; 
appIconImage.layer.masksToBounds = YES;
appIconImage.layer.cornerRadius = 10.0;
appIconImage.layer.borderWidth = 1.0;
appIconImage.layer.borderColor = [[UIColor grayColor] CGColor];

And also remember:

#import <QuartzCore/QuartzCore.h>

I cant offer any insight into your crash, but I thought I would offer another option for rounding the corners. I had a similar problem arise in an application i was working on. Rather than write any code I am overlaying another image which masks off the corners.