CIContext *context = [CIContext contextWithOptions:nil];
CIImage *inputImage = [[CIImage alloc] initWithImage:[UIImage imageNamed:@""]];
//创建高斯模糊滤镜
CIFilter *filter = [CIFilter filterWithName:@"CIGaussianBlur"];
[filter setValue:inputImage forKey:kCIInputImageKey];
[filter setValue:[NSNumber numberWithFloat:0] forKey:@"inputRadius"];
//生成模糊图片
CIImage *result = [filter valueForKey:kCIOutputImageKey];
CGImageRef cgImage = [context createCGImage:result fromRect:[result extent]];
UIImage *image = [UIImage imageWithCGImage:cgImage];
CGImageRelease(cgImage);
_backImageView.image = image;
//设置图片填充
_backImageView.contentMode = UIViewContentModeScaleAspectFill;
_backImageView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
//创建毛玻璃效果层
UIBlurEffect *iii = [UIBlurEffect effectWithStyle:UIBlurEffectStyleDark];
UIVisualEffectView *visualEffectView = [[UIVisualEffectView alloc] initWithEffect:iii];
visualEffectView.frame = _backImageView.frame;
//添加毛玻璃效果层
[_backImageView addSubview:visualEffectView];
