Objective-C 通过绘图裁剪图像

Question

我是 iOS 的新人。我想通过从用户那里绘制来裁剪图像。我在 google 上搜索了一天，但没有得到结果。 谢谢您的回答。

Answer 1

试试这个代码

  UIImagePickerController *picker=[[UIImagePickerController alloc] init];
    picker.delegate = self;
    [picker setAllowsEditing:YES];
    picker.sourceType=UIImagePickerControllerSourceTypeCamera;
    [self presentViewController:picker animated:YES completion:nil];

然后你可以从

中获取裁剪图像

  - (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
 {
  UIImage *image = [info valueForKey:UIImagePickerControllerEditedImage];
 picker dismissViewControllerAnimated:YES completion:^{}];

}

Answer 2

- (UIImage *)crop:(CGRect)rect {

    rect = CGRectMake(rect.origin.x*self.scale, 
                      rect.origin.y*self.scale, 
                      rect.size.width*self.scale, 
                      rect.size.height*self.scale);       

    CGImageRef imageRef = CGImageCreateWithImageInRect([self CGImage], rect);
    UIImage *result = [UIImage imageWithCGImage:imageRef 
                                          scale:self.scale 
                                    orientation:self.imageOrientation]; 
    CGImageRelease(imageRef);
    return result;
}