毛玻璃效果

UIImageView *imageView = [[UIImageView alloc] initWithFrame:self.view.frame];
imageView.image = [UIImage imageNamed:@"psb.jpg"];
[self.view addSubview:imageView];
    
UIVisualEffectView *blurView = [[UIVisualEffectView alloc] initWithEffect:[UIBlurEffect effectWithStyle:UIBlurEffectStyleLight]];
blurView.frame = imageView.frame;
[self.view addSubview:blurView];