UIImage合并和裁切

根据给定得图片，从其指定区域截取一张新得图片

[plain] view plain copy

1. -(UIImage *)getImageFromImage{  
2.   
3. //大图bigImage  
4.   
5. //定义myImageRect，截图的区域  
6.   
7. CGRect myImageRect = CGRectMake(10.0, 10.0, 57.0, 57.0);  
8.   
9. UIImage* bigImage= [UIImage imageNamed:@"k00030.jpg"];  
10.   
11. CGImageRef imageRef = bigImage.CGImage;  
12.   
13. CGImageRef subImageRef = CGImageCreateWithImageInRect(imageRef, myImageRect);  
14.   
15.    
16. CGSize size;  
17.   
18. size.width = 57.0;  
19.   
20. size.height = 57.0;  
21.   
22. UIGraphicsBeginImageContext(size);  
23.   
24. CGContextRef context = UIGraphicsGetCurrentContext();  
25.   
26. CGContextDrawImage(context, myImageRect, subImageRef);  
27.   
28. UIImage* smallImage = [UIImage imageWithCGImage:subImageRef];  
29.   
30. UIGraphicsEndImageContext();  
31.   
32.    
33. return smallImage;  
34.   
35. }  

Combine two UIImage

To add two UIImages together you need to make use of Graphics Context.

view plain copy to clipboard print ?

1. - (UIImage *)addImage:(UIImage *)image1 toImage:(UIImage *)image2 {  
2.     UIGraphicsBeginImageContext(image1.size);  
3.   
4.     // Draw image1  
5.     [image1 drawInRect:CGRectMake(0, 0, image1.size.width, image1.size.height)];  
6.   
7.     // Draw image2  
8.     [image2 drawInRect:CGRectMake(0, 0, image2.size.width, image2.size.height)];  
9.   
10.     UIImage *resultingImage = UIGraphicsGetImageFromCurrentImageContext();  
11.   
12.     UIGraphicsEndImageContext();  
13.   
14.     return resultingImage;  
15. }  

Save UIImage to Photo Album

This is just a one-liner:

1. UIImageWriteToSavedPhotosAlbum(image, self, @selector(imageSavedToPhotosAlbum: didFinishSavingWithError: contextInfo:), context);
   

And to know if the save was successful:

view plain copy to clipboard print ?

1. - (void)imageSavedToPhotosAlbum:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo {  
2.     NSString *message;  
3.     NSString *title;  
4.     if (!error) {  
5.         title = NSLocalizedString(@"SaveSuccessTitle", @"");  
6.         message = NSLocalizedString(@"SaveSuccessMessage", @"");  
7.     } else {  
8.         title = NSLocalizedString(@"SaveFailedTitle", @"");  
9.         message = [error description];  
10.     }  
11.     UIAlertView *alert = [[UIAlertView alloc] initWithTitle:title  
12.                                                     message:message  
13.                                                    delegate:nil  
14.                                           cancelButtonTitle:NSLocalizedString(@"ButtonOK", @"")  
15.                                           otherButtonTitles:nil];  
16.     [alert show];  
17.     [alert release];  
18. }