问IOS 7屏蔽问题-无法保存uiimageview中的屏蔽镜像

EN

//Masking the image
- (UIImage*) maskImage:(UIImage *)image withMask:(UIImage *)maskImage {

    CGImageRef maskRef = maskImage.CGImage; 

    CGImageRef mask = CGImageMaskCreate(CGImageGetWidth(maskRef),
                                        CGImageGetHeight(maskRef),
                                        CGImageGetBitsPerComponent(maskRef),
                                        CGImageGetBitsPerPixel(maskRef),
                                        CGImageGetBytesPerRow(maskRef),
                                        CGImageGetDataProvider(maskRef), NULL, false);

    CGImageRef masked = CGImageCreateWithMask([image CGImage], mask);
    return [UIImage imageWithCGImage:masked];
}


- (IBAction)savebtnclicked:(UIButton *)sender {


    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSString *savedImagePath = [documentsDirectory stringByAppendingPathComponent:@"savedImage2.png"];
    UIImage *image = _imageFinal.image; // imageView is my image from camera
    NSData *imageData = UIImagePNGRepresentation(image);
    [imageData writeToFile:savedImagePath atomically:NO];

}