- (void)viewDidLoad
{[super viewDidLoad];// Do any additional setup after loading the view, typically from a nib.// 滤镜效果NSArray *operations = @[@"CILinearToSRGBToneCurve",@"CIPhotoEffectChrome",@"CIPhotoEffectFade",@"CIPhotoEffectInstant",@"CIPhotoEffectMono",@"CIPhotoEffectNoir",@"CIPhotoEffectProcess",@"CIPhotoEffectTonal",@"CIPhotoEffectTransfer",@"CISRGBToneCurveToLinear",@"CIVignetteEffect"];CGFloat width = self.view.frame.size.width/3;CGFloat height = self.view.frame.size.height/4;NSMutableArray *imageViews = [NSMutableArray arrayWithCapacity:0];for (int i = 0; i < [operations count]; i++){UIImageView *imageView = [[UIImageView alloc]initWithFrame:CGRectMake(i%3*width, i/3*height, width, height)];imageView.image = [UIImage imageNamed:@"timg.jpeg"];[imageViews addObject:imageView];[self.view addSubview:imageView];}dispatch_async(dispatch_get_global_queue(0, 0),^{NSMutableArray *images = [NSMutableArray arrayWithCapacity:0];for (int i = 0; i < [operations count]; i++){UIImage *image = [UIImage imageNamed:@"timg.jpeg"];CIImage *cImage = [[CIImage alloc]initWithImage:image];//使用资源CIFilter *filter = [CIFilter filterWithName:operations[i]keysAndValues:kCIInputImageKey,cImage, nil];//使用默认参数
            [filter setDefaults];//生成上下文CIContext*context = [CIContext contextWithOptions:nil];//滤镜生成器输出图片CIImage *outputimage = [filter outputImage];//转换为UIImageCGImageRef ref = [context createCGImage:outputimage fromRect:[outputimage extent]];UIImage *temp = [UIImage imageWithCGImage:ref];[images addObject:temp];//释放CGImageRelease(ref);}dispatch_async(dispatch_get_main_queue(), ^{for (int x = 0; x < [images count]; x++){UIImageView *imageView = imageViews[x];imageView.image = images[x];}});});
}