iOS模糊效果的實現方法

2020-07-26 02:58:14

字體：大中小

來源：轉載

供稿：網友

本文實例為大家分享了iOS模糊效果的3種方法，供大家參考，具體內容如下

方案一：利用系統的CoreImage(濾鏡)

重點理解CIImage,CIFilter,CIContext,CGImageRef

濾鏡處理的過程比較慢,會造成加載圖片緩慢的現象(等一會才看到圖片),盡量放到子線程執行

- (void)viewDidLoad { [super viewDidLoad]; // 加載一張圖片 UIImage *image = [UIImage imageNamed:@"che"]; /**************CoreImage部分**************/ // 1.創建CIImage CIImage *ciImage = [[CIImage alloc] initWithImage:image]; // 2.創建濾鏡CIFilter CIFilter *blurFilter = [CIFilter filterWithName:@"CIGaussianBlur"]; // 2.1.將CIImage輸入到濾鏡中 [blurFilter setValue:ciImage forKey:kCIInputImageKey]; // 可以通過該方法查看我們可以設置的值(如模糊度等) NSLog(@"%@", [blurFilter attributes]); // 2.2設置模糊度 [blurFilter setValue:@(2) forKey:@"inputRadius"]; // 2.3將處理好的圖片輸出 CIImage *outCiImage = [blurFilter valueForKey:kCIOutputImageKey]; // 3.CIContext(option參數為nil代表用CPU渲染,若想用GPU渲染請查看此參數) CIContext *context = [CIContext contextWithOptions:nil]; // 4.獲取CGImage句柄 CGImageRef outCGImage = [context createCGImage:outCiImage fromRect:[outCiImage extent]]; // 5.獲取最終的圖片 UIImage *blurImage = [UIImage imageWithCGImage:outCGImage]; // 6.釋放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分類

將UIImage+ImageEffects.h和UIImage+ImageEffects.m文件加載進工程
包含UIImage+ImageEffects.h
UIImage+ImageEffects文件路徑

#import "ViewController.h"#import "UIImage+ImageEffects.h"- (void)viewDidLoad { [super viewDidLoad]; // 原始圖片 UIImage *sourceImage = [UIImage imageNamed:@"che"]; // 對圖片進行模糊處理 UIImage *blurImage = [sourceImage blurImageWithRadius:10]; // 加載模糊處理后的圖片 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,用于顯示動態模糊(背景能夠滾動,便于查看動態的模糊) 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.創建模糊view UIVisualEffectView *effectView = [[UIVisualEffectView alloc] initWithEffect:[UIBlurEffect effectWithStyle:UIBlurEffectStyleLight]]; // 2.設定模糊View的尺寸 effectView.frame = CGRectMake(0, 100, 375, 200); // 3.添加到view當中 [self.view addSubview:effectView]; /******************添加顯示文本******************/ 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.創建出子模糊view UIVisualEffectView *subEffectView = [[UIVisualEffectView alloc] initWithEffect:[UIVibrancyEffect effectForBlurEffect:(UIBlurEffect *)effectView.effect]]; // 2.設置子模糊view的尺寸 subEffectView.frame = effectView.bounds; // 3.將子模糊view添加到effectView的contentView上才能顯示 [effectView.contentView addSubview:subEffectView]; // 4.添加要顯示的view來達到特殊效果 [subEffectView.contentView addSubview:label];}@end

效果圖：