iOS图片模糊效果的实现方法

本文为大家分享了ios图片模糊效果的三种实现方式，供大家参考，具体内容如下

1.实现效果依次如图：原图、ios8效果、core image效果、 vimage 效果

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2. 代码

#import "viewcontroller.h" 
#import <accelerate/accelerate.h> 
 
@interface viewcontroller () 
 
@end 
 
@implementation viewcontroller 
 
- (void)viewdidload { 
 [super viewdidload]; 
 self.view.backgroundcolor = [uicolor colorwithpatternimage:[uiimage imagenamed:@"background"]]; 
  
// [self ios8blurimageimplement]; 
// [self coreimageimplement]; 
 [self vimageimplement]; 
} 
 
// ios8 使用系统自带的处理方式 
- (void)ios8blurimageimplement { 
 uiblureffect *beffect = [uiblureffect effectwithstyle:uiblureffectstylelight]; 
 uivisualeffectview *view = [[uivisualeffectview alloc] initwitheffect:beffect]; 
 view.frame = self.view.bounds; 
 [self.view addsubview:view]; 
} 
 
 
// 使用coreimage实现图片模糊 
- (void)coreimageimplement{ 
 cicontext *context = [cicontext contextwithoptions:nil]; 
  
 nserror *error = nil; 
 nsstring *filepath = [[nsbundle mainbundle] pathforresource:@"background" oftype:@"png"]; 
 nsdata *imagedata = [nsdata datawithcontentsoffile:filepath options:nsdatareadinguncached error:&error]; 
  
 //nsdata *imagedata = [nsdata datawithcontentsoffile:@"background.png"]; 
 ciimage *image = [ciimage imagewithdata:imagedata]; 
 cifilter *filter = [cifilter filterwithname:@"cigaussianblur"]; 
 [filter setvalue:image forkey:kciinputimagekey]; 
 [filter setvalue:@2.0f forkey:@"inputradius"]; 
 ciimage *result = [filter valueforkey:kcioutputimagekey]; 
 cgimageref outimage = [context createcgimage:result fromrect:[result extent]]; 
 uiimage *bluerimage = [uiimage imagewithcgimage:outimage]; 
  
 uiimageview *imageview = [[uiimageview alloc] initwithimage:bluerimage]; 
 imageview.frame = self.view.bounds; 
 [self.view addsubview:imageview]; 
} 
 
 
// 使用vimage api实现图片模糊 
// ios5.0中新增了vimage api可以使用，它属于accelerate.framework，所以如果你要使用它要在工程中加入这个framework。模糊算法使用的是vimageboxconvolve_argb8888这个函数。 
- (void)vimageimplement { 
 uiimage *image = [uiimage imagenamed:@"background"]; 
 uiimage *blurimage = [self blurryimage:image withblurlevel:0.5]; 
 self.view.backgroundcolor = [uicolor colorwithpatternimage:blurimage]; 
} 
 
- (uiimage *)blurryimage:(uiimage *)image withblurlevel:(cgfloat)blur { 
 if (blur < 0.f || blur > 1.f) { 
  blur = 0.5f; 
 } 
 int boxsize = (int)(blur * 100); 
 boxsize = boxsize - (boxsize % 2) + 1; 
  
 cgimageref img = image.cgimage; 
  
 vimage_buffer inbuffer, outbuffer; 
 vimage_error error; 
  
 voidvoid *pixelbuffer; 
  
 cgdataproviderref inprovider = cgimagegetdataprovider(img); 
 cfdataref inbitmapdata = cgdataprovidercopydata(inprovider); 
  
 inbuffer.width = cgimagegetwidth(img); 
 inbuffer.height = cgimagegetheight(img); 
 inbuffer.rowbytes = cgimagegetbytesperrow(img); 
  
 inbuffer.data = (void*)cfdatagetbyteptr(inbitmapdata); 
  
 pixelbuffer = malloc(cgimagegetbytesperrow(img) * 
       cgimagegetheight(img)); 
  
 if(pixelbuffer == null) 
  nslog(@"no pixelbuffer"); 
  
 outbuffer.data = pixelbuffer; 
 outbuffer.width = cgimagegetwidth(img); 
 outbuffer.height = cgimagegetheight(img); 
 outbuffer.rowbytes = cgimagegetbytesperrow(img); 
  
 error = vimageboxconvolve_argb8888(&inbuffer, 
          &outbuffer, 
          null, 
          0, 
          0, 
          boxsize, 
          boxsize, 
          null, 
          kvimageedgeextend); 
  
  
 if (error) { 
  nslog(@"error from convolution %ld", error); 
 } 
  
 cgcolorspaceref colorspace = cgcolorspacecreatedevicergb(); 
 cgcontextref ctx = cgbitmapcontextcreate( 
            outbuffer.data, 
            outbuffer.width, 
            outbuffer.height, 
            8, 
            outbuffer.rowbytes, 
            colorspace, 
            kcgimagealphanoneskiplast); 
 cgimageref imageref = cgbitmapcontextcreateimage (ctx); 
 uiimage *returnimage = [uiimage imagewithcgimage:imageref]; 
  
 //clean up 
 cgcontextrelease(ctx); 
 cgcolorspacerelease(colorspace); 
  
 free(pixelbuffer); 
 cfrelease(inbitmapdata); 
  
 cgcolorspacerelease(colorspace); 
 cgimagerelease(imageref); 
  
 return returnimage; 
} 
 
@end 

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。