CIFilter (模糊图片)

 //使用模糊图片

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {

    [super viewDidLoad];

    

    UIImage *image = [UIImage imageNamed:@"qiaodan"];

    

    //coreImage

    CIImage *ciImage = [[CIImage alloc] initWithImage:image];

    CIFilter *blurFilter = [CIFilter filterWithName:@"CIGaussianBlur"];

    //设置模糊程度

    [blurFilter setValue:@(2) forKey:@"inputRadius"];

    //查询滤镜设置参数的信息

    NSLog(@"%@",[blurFilter attributes]);

    //将图片输入到滤镜中

    [blurFilter setValue:ciImage forKey:kCIInputImageKey];

    //将处理好的图片输出

    CIImage *outCiImage = [blurFilter valueForKey:kCIOutputImageKey];

    

    //CIContext

    CIContext *context = [CIContext contextWithOptions:nil];

    //获取CGImage句柄

    CGImageRef outCGImage = [context createCGImage:outCiImage fromRect:[outCiImage extent]];

    //最终获取到图片

    UIImage *blurImage = [UIImage imageWithCGImage:outCGImage];

    //释放CGImage句柄

    CGImageRelease(outCGImage);

        

    //图片初始化

    UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 640/2.f, 640/2.f)];

    imageView.image = blurImage;

    imageView.center = self.view.center;

    [self.view addSubview:imageView];   

    

    // Do any additional setup after loading the view, typically from a nib.

}

- (void)didReceiveMemoryWarning {

    [super didReceiveMemoryWarning];

    // Dispose of any resources that can be recreated.

}

@end