最近在某些app 上面看到banner 图 的图片虚化，然后花了一点时间去处理了这个问题
#import "ViewController.h"
@interface ViewController ()
@property(nonatomic,strong)UIImageView *imageView;
@property(nonatomic,strong)UIImageView *imgView;
@end
@implementation ViewController
//懒加载
- (UIImageView *)imageView
{
if (_imageView ==nil) {
_imageView = [[UIImageViewalloc]initWithFrame:CGRectMake(0,0, 200,200)];
_imageView.backgroundColor = [UIColororangeColor];
}
return_imageView;
}
- (UIImageView *)imgView
{
if (_imgView ==nil) {
_imgView = [[UIImageViewalloc]initWithFrame:CGRectMake(0,300, 200, 200)];
_imgView.backgroundColor = [UIColororangeColor];
}
return_imgView;
}
- (void)viewDidLoad {
[superviewDidLoad];
[self dealImgView1];
[self text];
}
- (void)dealImgView1 {
// coreImage是IOS5中新加入的一个Objective-c的框架，提供了强大高效的图像处理功能，用来对基于像素的图像进行操作与分析。iOS提供了很多强大的滤镜(Filter)，现在有127种之多,随着框架的更新，这一数字会继续增加。这些Filter提供了各种各样的效果，并且还可以通过滤镜链将各种效果的Filter叠加起来，形成强大的自定义效果，如果你对该效果很满意，还可以子类化滤镜。下面将代码贴在下面,与大家分享,如果对框架不熟悉,建议阅读苹果的官方API.
[self.viewaddSubview:self.imgView];
CIImage *inputImage = [[CIImagealloc] initWithImage:[UIImage imageNamed:@"图片的名字"]];
//CIFilter,高斯模糊滤镜
CIFilter *filter = [CIFilterfilterWithName:@"CIGaussianBlur"];
//将图片输入到滤镜中
[filter setValue:inputImage forKey:kCIInputImageKey];
//设置模糊程度,默认为10,取值范围(0-100)
[filter setValue:[NSNumbernumberWithFloat:10.0]forKey:@"inputRadius"];
//将处理好的图片输出
CIImage *result = [filter valueForKey:kCIOutputImageKey];
//CIImage *result=[filter outputImage];//两种方法都可以
CIContext *context = [CIContextcontextWithOptions:nil];
//获取CGImage句柄,也就是从数据流中取出图片
CGImageRef cgImage = [context createCGImage:result fromRect:[inputImageextent]];
#warning result inputImage 变化不同（）
// CGImageRef cgImage = [context createCGImage:result fromRect:[result extent]];
//最终获取到图片
UIImage *image = [UIImageimageWithCGImage:cgImage];
//释放CGImage句柄
CGImageRelease(cgImage);
self.imgView.image=image;
}
下面是虚化的样子
为什么会出现两个呢 而且不同的虚化模式
关键是：有一句代码不一样
//获取CGImage句柄,也就是从数据流中取出图片
CGImageRef cgImage = [context createCGImage:result fromRect:[inputImage extent]];
#warning result inputImage 变化不同（）
// CGImageRef cgImage = [context createCGImage:result fromRect:[result extent]];
[inputImage extent ] 一个是处理前的图片 一个是处理后的图片 [result extent]
附录：
//用来查询滤镜可以设置的参数以及一些相关的信息
NSLog(@"%@",[filterattributes]);
/*
[blurFilter attributes]打印结果如下:
//参数以及一些相关的信息,如果不做任何的设置,默认程度为10( CIAttributeDefault = 10);
2016-08-01 17:02:44.552 钱钱钱钱钱[6935:207227] {
"CIAttributeFilterAvailable_Mac" = "10.4";
"CIAttributeFilterAvailable_iOS" = 6;
CIAttributeFilterCategories = (
CICategoryBlur,
CICategoryStillImage,
CICategoryVideo,
CICategoryBuiltIn
);
CIAttributeFilterDisplayName = "Gaussian Blur";
CIAttributeFilterName = CIGaussianBlur;
CIAttributeReferenceDocumentation = "http://developer.apple.com/cgi-bin/apple_ref.cgi?apple_ref=//apple_ref/doc/filter/ci/CIGaussianBlur";
inputImage = {
CIAttributeClass = CIImage;
CIAttributeDescription = "The image to use as an input image. For filters that also use a background image, this is the foreground image.";
CIAttributeDisplayName = Image;
CIAttributeType = CIAttributeTypeImage;
};
inputRadius = {
CIAttributeClass = NSNumber;
CIAttributeDefault = 10;
CIAttributeDescription = "The radius determines how many pixels are used to create the blur. The larger the radius, the blurrier the result.";
CIAttributeDisplayName = Radius;
CIAttributeIdentity = 0;
CIAttributeMin = 0;
CIAttributeSliderMax = 100;
CIAttributeSliderMin = 0;
CIAttributeType = CIAttributeTypeScalar;
};
}
*/
更多的博客请登录
http://write.blog.csdn.net/postlist/0/0/enabled/2