// 从view上截图        - (UIImage *)getImage {                        UIGraphicsBeginImageContextWithOptions(CGSizeMake(150, 150), NO, 1.0);  //NO，YES 控制是否透明            [self.view.layer renderInContext:UIGraphicsGetCurrentContext()];            UIImage *image = UIGraphicsGetImageFromCurrentImageContext();            UIGraphicsEndImageContext();            // 生成后的image                        return image;        }                // 根据给定得图片，从其指定区域截取一张新得图片        -(UIImage *)getImageFromImage{            //大图bigImage            //定义myImageRect，截图的区域            CGRect myImageRect = CGRectMake(70, 10, 150, 150);            UIImage* bigImage= [UIImage imageNamed:@"mm.jpg"];            CGImageRef imageRef = bigImage.CGImage;            CGImageRef subImageRef = CGImageCreateWithImageInRect(imageRef, myImageRect);            CGSize size;            size.width = 150;            size.height = 150;            UIGraphicsBeginImageContext(size);            CGContextRef context = UIGraphicsGetCurrentContext();            CGContextDrawImage(context, myImageRect, subImageRef);            UIImage* smallImage = [UIImage imageWithCGImage:subImageRef];            UIGraphicsEndImageContext();            return smallImage;        }