方案一:利用系统的
CoreImage(滤镜)
重点理解
CIImage,CIFilter,CIContext,CGImageRef滤镜处理的过程比较慢,会造成加载图片缓慢的现象(等一会才看到图片),尽量放到子线程执行
- (void)viewDidLoad {
[super viewDidLoad];
// 加载一张图片
UIImage *image = [UIImage imageNamed:@"che"];
/**************CoreImage部分**************/
// 1.创建CIImage
CIImage *ciImage = [[CIImage alloc] initWithImage:image];
// 2.创建滤镜CIFilter
CIFilter *blurFilter = [CIFilter filterWithName:@"CIGaussianBlur"];
// 2.1.将CIImage输入到滤镜中
[blurFilter setValue:ciImage forKey:kCIInputImageKey];
// 可以通过该方法查看我们可以设置的值(如模糊度等)
NSLog(@"%@", [blurFilter attributes]);
// 2.2设置模糊度
[blurFilter setValue:@(2) forKey:@"inputRadius"];
// 2.3将处理好的图片输出
CIImage *outCiImage = [blurFilter valueForKey:kCIOutputImageKey];
// 3.CIContext(option参数为nil代表用CPU渲染,若想用GPU渲染请查看此参数)
CIContext *context = [CIContext contextWithOptions:nil];
// 4.获取CGImage句柄
CGImageRef outCGImage = [context createCGImage:outCiImage fromRect:[outCiImage extent]];
// 5.获取最终的图片
UIImage *blurImage = [UIImage imageWithCGImage:outCGImage];
// 6.释放CGImage
CGImageRelease(outCGImage);
/*****************************************/
UIImageView *imageV = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 750 / 2, 1334 / 2)];
imageV.image = blurImage;
imageV.center = self.view.center;
[self.view addSubview:imageV];
}
方案二:利用UIImage+ImageEffects分类
- 将
UIImage+ImageEffects.h和UIImage+ImageEffects.m文件加载进工程 - 包含
UIImage+ImageEffects.h -
UIImage+ImageEffects文件路径
#import "ViewController.h"
#import "UIImage+ImageEffects.h"
- (void)viewDidLoad {
[super viewDidLoad];
// 原始图片
UIImage *sourceImage = [UIImage imageNamed:@"che"];
// 对图片进行模糊处理
UIImage *blurImage = [sourceImage blurImageWithRadius:10];
// 加载模糊处理后的图片
UIImageView *imageV = [[UIImageView alloc] initWithImage:blurImage];
[self.view addSubview:imageV];
}
方案三:利用UIVisualEffectView(iOS8)
#import "ViewController.h"
@interface ViewController ()
/** 背景 */
@property (nonatomic, strong) UIScrollView *scrollView;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
// 添加展示的背景,用于显示动态模糊(背景能够滚动,便于查看动态的模糊)
self.scrollView = [[UIScrollView alloc] initWithFrame:self.view.bounds];
UIImageView *imageV = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"fengjing"]];
self.scrollView.contentSize = imageV.image.size;
self.scrollView.bounces = NO;
[self.scrollView addSubview:imageV];
[self.view addSubview:self.scrollView];
/***************添加模糊效果***************/
// 1.创建模糊view
UIVisualEffectView *effectView = [[UIVisualEffectView alloc] initWithEffect:[UIBlurEffect effectWithStyle:UIBlurEffectStyleLight]];
// 2.设定模糊View的尺寸
effectView.frame = CGRectMake(0, 100, 375, 200);
// 3.添加到view当中
[self.view addSubview:effectView];
/******************添加显示文本******************/
UILabel *label = [[UILabel alloc] initWithFrame:effectView.bounds];
label.text = @"模糊效果";
label.font = [UIFont systemFontOfSize:40];
label.textAlignment = NSTextAlignmentCenter;
/****************添加模糊效果的子view****************/
// 1.创建出子模糊view
UIVisualEffectView *subEffectView = [[UIVisualEffectView alloc] initWithEffect:[UIVibrancyEffect effectForBlurEffect:(UIBlurEffect *)effectView.effect]];
// 2.设置子模糊view的尺寸
subEffectView.frame = effectView.bounds;
// 3.将子模糊view添加到effectView的contentView上才能显示
[effectView.contentView addSubview:subEffectView];
// 4.添加要显示的view来达到特殊效果
[subEffectView.contentView addSubview:label];
}
@end
iOS8-模糊效果.gif
