CoreImage 中的模糊滤镜

1.CoreImage 中的模糊滤镜

1.1CoreImage是苹果用来简化图片处理的框架

1.2CIImage、CIFilter与CIContext三者联系

1.3CIGaussianBlur中可能设置的參数

2.UIImage+imageEffects的category模糊效果

3.iOS8中的UIVisualEffectView模糊效果的使用方法

一、.CoreImage 中的模糊滤镜

- (void)coreImageBlur

{

//原始图片

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

//CoreImage部分--------------------

//CIImage

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

//CIFilter

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

//将图片输入到滤镜中

[blurFilter setValue:ciImage forKey:kCIInputImageKey];

//设置模糊程序

[blurFilter setValue:@(1) forKey:@"inputRadius"];

//用业查询滤镜能够设置的參数以及一引起相关的信息

NSLog(@"%@",[blurFilter attributes]);

//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]];

//终于获取到图片

UIImage *blurImage      = [UIImage imageWithCGImage:outCGImage];

//释放CGImage句柄

CGImageRelease(outCGImage);

//---------------------------------

//

//初始化UIImageView

UIImageView *imageView = \

/2.0)];

imageView.image         =  blurImage;

imageView.center        = self.view.center;

[self.view addSubview:imageView];

}

二、UIImage+ImageEffects的category
模糊效果

1.UIImage+ImageEffects是Accelerate框架中的内容

2.UIImage+ImageEffects的模糊效果很美观

3.改动过的UIImage+ImageEffects能够对图片进行局模糊

#import "UIImage+ImageEffects.h"

- (void)effectiveImages

{

UIImage *sourceImage = [UIImage imageNamed:@"normal"];

CGSize  imageSize    = sourceImage.size;

, ,
imageSize., imageSize.height )];

UIImageView *imageView = [[UIImageView alloc]initWithImage:blurImage];

imageView.center        = self.view.center;

[self.view addSubview:imageView];

}

UIImage+ImageEffects 下载地址:http://download.csdn.net/detail/baitxaps/8893093

三、iOS8 中 UIVisualEffectView 模糊效果的使用

1.UIVisualEffectView的模糊效果是即时渲染的

2.要注意处理在UIVisualEffectiView之上的文本显示

3.仅仅能在iOS8以上才可以使用UIVisualEffectiView

- (void)visualEffectImage

{

UIScrollView *scrollView = [[UIScrollView alloc]initWithFrame:self.view.bounds];

UIImageView *imageView      = [[UIImageView alloc]initWithImage:[UIImageimageNamed:@"normal"]];

scrollView.contentSize      = imageView.image.size;

scrollView.bounces           = NO;

[scrollView addSubview:imageView];

[self.view addSubview:scrollView];

/*加入模糊效果*/

//1.创建模糊View

UIVisualEffectView *effectView = [[UIVisualEffectView alloc]initWithEffect:[UIBlurEffecteffectWithStyle:UIBlurEffectStyleLight ]];

//2.设定尺寸

effectView., , , );

//3.加入到View其中

[self.view addSubview:effectView];

//4.加入显示文本

UILabel *label = [[UILabel alloc]initWithFrame:effectView.bounds];

label.text      = @"hello world";

label.];

label.textAlignment = NSTextAlignmentCenter;

// [effectView.contentView addSubview:label];

//5.

//加入模糊子View的UIVisualEffectView

//1.创建出子模糊View

UIVisualEffectView *subEffectView = [[UIVisualEffectView alloc]initWithEffect:[UIVibrancyEffect effectForBlurEffect:(UIBlurEffect *)effectView.effect]];

//2.设定尺寸

subEffectView.frame = effectView.bounds;

//3.将子模糊View加入到effective的contentView才干生效

[effectView.contentView addSubview:subEffectView];

//4.加入要显示的View来达到特殊的效果

[subEffectView.contentView addSubview:label];

}

四、设计下载图片后自己主动模糊的控件

1.用KVO监听下载完毕后的事件

2.在子线程中进行渲染。主线程中进行图片的载入

3.新建一个下载类,GCD看前面博客文档GCD的封装

@interface BlurDownloadPicView : UIView

@property (nonatomic,strong)NSString *pictureUrlString;//图片下载地址

@property (nonatomic)       UIViewContentMode contentMode;//图片显示方式

//開始运行

- (void)startProgress;

@end

#import "UIImage+ImageEffects.h"

#import "BlurDownloadPicView.h"

#import "GCD.h"

@interface BlurDownloadPicView()

@property (nonatomic,strong)UIImageView *imageView;

@end

@implementation BlurDownloadPicView

- (instancetype)initWithFrame:(CGRect)frame{

self = [super initWithFrame:frame];

if (self) {

//初始化控件

//最好放一个方法中

self.imageView = [[UIImageView alloc]initWithFrame:self.bounds];

self.imageView.alpha = 0.f;

[self addSubview:self.imageView];

}

return self;

}

- (void)startProgress{

if (self.pictureUrlString)
{

[GCDQueue executeInGlobalQueue:^{

//创建请求

NSURLRequest *request = [NSURLRequest requestWithURL:

[NSURL URLWithString:self.pictureUrlString]];

//由于是同步请求。会堵塞主线程

NSData *data = [NSURLConnection sendSynchronousRequest:request

returningResponse:nil

error:nil];

UIImage *image = [[UIImage alloc]initWithData:data];

//对图片进行模糊。会堵塞主线程

UIImage *blurImage = [image blurImage];

[GCDQueue executeInMainQueue:^{

[UIView animateWithDuration:1.0 animations:^{

self.imageView.alpha = 1.f;

}];

self.imageView.image = blurImage;

}];

}];

}

}

@synthesize contentMode = _contentMode;

- (void)setContentMode:(UIViewContentMode)contentMode{

_contentMode = contentMode;

self.imageView.contentMode = contentMode;

}

- (UIViewContentMode)contentMode{

return _contentMode;

}

@end

4.使用

- (void)viewDidLoad {

[super viewDidLoad];

//[self coreImageBlur];

//[self visualEffectImage];

NSString *picUrlString = @"http://t1.mmonly.cc/uploads/allimg/tuku2/14400BR6-0.jpg";

BlurDownloadPicView *blurDownLoadView = [[BlurDownloadPicView alloc]initWithFrame:self.view.bounds];

blurDownLoadView.center               = self.view.center;

[self.view addSubview:blurDownLoadView];

blurDownLoadView.pictureUrlString = picUrlString;

blurDownLoadView.contentMode       = UIViewContentModeScaleAspectFill;

[blurDownLoadView startProgress];

}