1.使用CoreImage中的模糊濾鏡原始效果圖如下:
CoreImage的實(shí)現(xiàn):
- (void)viewDidLoad {
[super viewDidLoad];
UIImage * image = [UIImage imageNamed:@"icon"];
/*..CoreImage中的模糊效果濾鏡..*/
//CIImage,相當(dāng)于UIImage,作用為獲取圖片資源
CIImage * ciImage = [[CIImage alloc]initWithImage:image ];
//CIFilter,高斯模糊濾鏡
CIFilter * blurFilter = [CIFilter filterWithName:@"CIGaussianBlur"];
//將圖片輸入到濾鏡中
[blurFilter setValue:ciImage forKey:kCIInputImageKey];
//用來查詢?yōu)V鏡可以設(shè)置的參數(shù)以及一些相關(guān)的信息
NSLog(@"%@",[blurFilter attributes]);
//設(shè)置模糊程度,默認(rèn)為10,取值范圍(0-100)
[blurFilter setValue:@(20) forKey:@"inputRadius"];
//將處理好的圖片輸出
CIImage * outCiImage = [blurFilter valueForKey:kCIOutputImageKey];
//CIContext
CIContext * context = [CIContext contextWithOptions:nil];
//獲取CGImage句柄,也就是從數(shù)據(jù)流中取出圖片
CGImageRef outCGImage = [context createCGImage:outCiImage fromRect:[outCiImage extent]];
//最終獲取到圖片
UIImage * blurImage = [UIImage imageWithCGImage:outCGImage];
//釋放CGImage句柄
CGImageRelease(outCGImage);
UIImageView * imageView = [[UIImageView alloc]initWithFrame:self.view.bounds]; imageView.image = blurImage; [self.view addSubview:imageView];
}
[blurFilter attributes]打印結(jié)果如下:
//參數(shù)以及一些相關(guān)的信息,如果不做任何的設(shè)置,默認(rèn)程度為10( CIAttributeDefault = 10);
{
"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;
};
}```
默認(rèn)程度為10效果圖如下:![這里寫圖片描述](http://upload-images.jianshu.io/upload_images/1485325-cc76711e082f0adf?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240) 默認(rèn)程度為50效果圖如下:![這里寫圖片描述](http://upload-images.jianshu.io/upload_images/1485325-d7bb4a6c24460d6b?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
#### 2.使用UIImage+ImageEffects
到該地址下載:https://github.com/YouXianMing/UIImageBlur,里面還有很多好東西,值得關(guān)注;
導(dǎo)入U(xiǎn)IImage+ImageEffects文件到工程中即可使用;
UIImage+ImageEffects的實(shí)現(xiàn):
UIImage * image = [UIImage imageNamed:@"icon"];
//模糊效果渲染耗費(fèi)時間,建議在子線程中渲染
//對圖片進(jìn)行模糊
UIImage * blurImage = [image blurImage];
//設(shè)置模糊度
UIImage * blurImage1 = [image blurImageWithRadius:10];
//設(shè)置局部模糊度
UIImage * blurImage2 = [image blurImageAtFrame:CGRectMake(0, 0, image.size.width, image.size.height/2)];
//灰度效果
UIImage * blurImage3 = [image grayScale];
/*其他的一些方法,可以自己嘗試使用
//固定寬度與固定高度
- (UIImage *)scaleWithFixedWidth:(CGFloat)width;
- (UIImage *)scaleWithFixedHeight:(CGFloat)height;
//平均的顏色 - (UIColor *)averageColor;
//裁剪圖片的一部分 - (UIImage *)croppedImageAtFrame:(CGRect)frame;
*/
UIImageView * imageView = [[UIImageView alloc]initWithFrame:self.view.bounds]; imageView.image = blurImage; [self.view addSubview:imageView];
效果圖分別如下:![這里寫圖片描述](http://upload-images.jianshu.io/upload_images/1485325-b12d3ce7472c76ac?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
//局部模糊![這里寫圖片描述](http://upload-images.jianshu.io/upload_images/1485325-93df8f7fcf05914d?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
//灰色![這里寫圖片描述](http://upload-images.jianshu.io/upload_images/1485325-a451ee652ba02b89?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
#### 3.使用UIVisualEffectView
注意:UIVisualEffectView只適用用戶iOS 8或以上,才可以使用8以下則不能使用;
UIVisualEffectView的實(shí)現(xiàn):
1.直接將文本內(nèi)容加在effectView(該情況下的文本內(nèi)容不能與背景相符應(yīng));
UIImage * image = [UIImage imageNamed:@"icon"];
UIImageView * imageView = [[UIImageView alloc]initWithFrame:self.view.bounds]; imageView.image = image;
[self.view addSubview:imageView];
UIBlurEffect * blur = [UIBlurEffect effectWithStyle:UIBlurEffectStyleLight];
//創(chuàng)建模糊view
UIVisualEffectView * effectView = [[UIVisualEffectView alloc]initWithEffect:blur];
effectView.frame = CGRectMake(0, 250, imageView.frame.size.width, 200);
[imageView addSubview:effectView];
//添加顯示文本
UILabel * lable = [[UILabel alloc]initWithFrame:effectView.bounds];
lable.text = @"哈哈哈哈哈";
lable.textAlignment = NSTextAlignmentCenter;
lable.font = [UIFont systemFontOfSize:24];
[effectView.contentView addSubview:lable];
效果圖如下:![這里寫圖片描述](http://upload-images.jianshu.io/upload_images/1485325-54bee101c7ac7010?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
2.加在effectView的子view中使文本與背景相符應(yīng);
UIImage * image = [UIImage imageNamed:@"icon"];
UIImageView * imageView = [[UIImageView alloc]initWithFrame:self.view.bounds]; imageView.image = image; [self.view addSubview:imageView];
UIBlurEffect * blur = [UIBlurEffect effectWithStyle:UIBlurEffectStyleLight];
//創(chuàng)建模糊view
UIVisualEffectView * effectView = [[UIVisualEffectView alloc]initWithEffect:blur];
effectView.frame = CGRectMake(0, 250, imageView.frame.size.width, 200);
[imageView addSubview:effectView];
//添加顯示文本
UILabel * lable = [[UILabel alloc]initWithFrame:effectView.bounds];
lable.text = @"哈哈哈哈哈";
lable.textAlignment = NSTextAlignmentCenter;
lable.font = [UIFont systemFontOfSize:24];
//創(chuàng)建模糊子view的UIVisualEffectView
//1.創(chuàng)建出子模糊view
UIVisualEffectView * subEffectView = [[UIVisualEffectView alloc]initWithEffect:[UIVibrancyEffect effectForBlurEffect:(UIBlurEffect *)effectView.effect]];
//2.設(shè)定尺寸
subEffectView.frame = effectView.bounds;
//3.將子模糊view添加到effectView的contentView才能夠生效
[effectView.contentView addSubview:subEffectView];
//4.添加要顯示的view來達(dá)到特殊的效果
[subEffectView.contentView addSubview:lable];
效果圖如下:![這里寫圖片描述](http://upload-images.jianshu.io/upload_images/1485325-f6f2a722e7e51bc4?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
#### 4.下載圖片后自動模糊效果
在項(xiàng)目中導(dǎo)入U(xiǎn)IImage+ImageEffects和GCD文件;
UIImage+ImageEffects地址:https://github.com/YouXianMing/UIImageBlur;
GCD地址:https://github.com/YouXianMing/GCD-Program;
代碼的實(shí)現(xiàn):
創(chuàng)建一個UIView的子類,命名為BlurDownloadPicView;
BlurDownloadPicView.h的里面內(nèi)容:
import <UIKit/UIKit.h>@interface BlurDownloadPicView : UIView
//圖片下載地址
@property (nonatomic, strong)NSString * picUrl;
//圖片顯示的方式
@property (nonatomic)UIViewContentMode contentMode;
//開始執(zhí)行
- (void)startProgress;
@end
BlurDownloadPicView.m的里面內(nèi)容:
import "BlurDownloadPicView.h"
import "GCD.h"
import "UIImage+ImageEffects.h"
@interface BlurDownloadPicView ()
@property (nonatomic, strong)UIImageView * imageView;
@end
@implementation BlurDownloadPicView
- (instancetype)initWithFrame:(CGRect)frame{
self = [super initWithFrame:frame];
if (self) {
[self loadSubViews];
}
return self;
} - (void)loadSubViews{
self.imageView = [[UIImageView alloc]initWithFrame:self.bounds];
self.imageView.alpha = 0;
[self addSubview:self.imageView];
} - (void)startProgress{
if (self.picUrl) {
[GCDQueue executeInGlobalQueue:^{
//創(chuàng)建請求
NSURLRequest * request = [NSURLRequest requestWithURL:[NSURL URLWithString:self.picUrl]]; //因?yàn)槭峭秸埱?會阻塞主線程(mainQueue)
NSData * data = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
//獲取圖片
UIImage * image = [[UIImage alloc]initWithData:data];
//對圖片進(jìn)行模糊,會阻塞主線程(mainQueue)
UIImage * blurImage = [image blurImage];
[GCDQueue executeInMainQueue:^{
//加載圖片
self.imageView.image = blurImage;
[UIView animateWithDuration:1 animations:^{
self.imageView.alpha = 1;
}];
}];
}];
}
}
//重寫set,get方法
-(void)setContentMode:(UIViewContentMode)contentMode{
self.contentMode = contentMode;
self.imageView.contentMode = contentMode;
} - (UIViewContentMode)contentMode{
return self.contentMode;}
在ViewController.m里面的實(shí)現(xiàn);
引入#import "BlurDownloadPicView.h"頭文件
在viewDidLoad里面的代碼實(shí)現(xiàn)
- (void)viewDidLoad {
[super viewDidLoad];
NSString * picUrl = @"http://i4.download.fd.pchome.net/g1/M00/0D/1C/oYYBAFTEeAmIWRXgAAKhY5iKdP8AACP_QP4y0IAAqF7878.jpg";
BlurDownloadPicView * blurPicView = [[BlurDownloadPicView alloc]initWithFrame:self.view.bounds];
[self.view addSubview:blurPicView];
blurPicView.picUrl = picUrl;
[blurPicView startProgress];
}
效果圖如下:![這里寫圖片描述](http://upload-images.jianshu.io/upload_images/1485325-6d0fc61a9677e700?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)