iOS模糊效果的实现方法

本文实例为大家分享了ios模糊效果的3种方法，供大家参考，具体内容如下

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

效果图：

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。