Face++人脸识别小demo

人脸识别技术概念

所谓人脸识别技术，即基于人的脸部特征，对输入的人脸图象或者视频流进行判断，首先判断其是否存在人脸。如果存在人脸，则进一步的给出每个脸的位置、大小和各个主要面部器官的位置信息。并依据这些信息，进一步提取每个人脸中所蕴涵的身份特征，并将其与已知的人脸进行对比，从而识别每个人脸的身份。

人脸识别技术的发展前景

在这个刷脸的时代,人脸识别技术怎能不火。人脸识别技术，是目前生物科技上在可行性，稳定性和准确性等专业技术指标中数值最高的技术。也是目前各行各业安全保卫中运用最广，效果最好的一种技术。在未来的几年内，它必将超越指纹识别等生物技术，成为生物识别技术领域的霸主。

列举人脸识别在手机APP上的一些应用

1.美图秀秀邪恶大测试:识别面部表情,给出分数和评价
2.百度图片识图功能
3.百度魔图APP推出了“PK大咖”功能，用户只需要选取一张自己的大头照，就可以通过人脸识别技术跟明星进行PK，找到与你面部形象最为相似的明星大咖
4.百度钱包APP拍照付只是说当你想买一款商品，却不知道商品的具体信息，这时候就可以用到百度钱包的拍照付，拍一下就能搜索到商品，选择购买
5.支付宝APP人脸识别登录
6.iPhoto 在苹果的iPhoto中，同样提供了人脸识别功能，用户可以将图片中的人脸和人名相匹配，该功能通过脸部检测辨别照片中的人物，再通过脸部识别找到与之特征相符的拍摄对象，帮你找到想找的人，甚至是海量的照片库也不费吹灰之力
7.图图搜是先找到淘宝上的同款，然后拿到产品tag，接着根据tag、主颜色等信息进行二次查找。最基本的技术还是相同图像查找，当然也包含了商品主体识别。

Face++ 人脸识别demo

主要实现的功能是:给出两张面孔,判断两张面孔的相似度
封装YYFaceViewController
.h文件

// //  YYFaceViewController.h //  Demo_Face++ // //  Created by yyMae on 15/12/25. //  Copyright (c) 2015年 yyMae. All rights reserved. // #import  @interface YYFaceViewController : UIViewController<UINavigationControllerDelegate,UIImagePickerControllerDelegate> @end

.m文件

// //  YYFaceViewController.m //  Demo_Face++ // //  Created by yyMae on 15/12/25. //  Copyright (c) 2015年 yyMae. All rights reserved. // #import "YYFaceViewController.h" #import "FaceppAPI.h" #define kwidth self.view.frame.size.width #define height self.view.frame.size.height #define btnBorder 40 #define imgBorder 20 @interface YYFaceViewController () //显示图片的imageView @property (nonatomic,strong) UIImageView *firstImgV; @property (nonatomic,strong) UIImageView *secondImgV; //触发比较相似度的button @property (nonatomic,strong) UIButton *recognizedBtn; //五官的相似度 @property (nonatomic,strong) NSString *eye; @property (nonatomic,strong) NSString *eyebrow; @property (nonatomic,strong) NSString *mouth; @property (nonatomic,strong) NSString *nose; @property (nonatomic,strong) NSString *similarity; @property (nonatomic,strong) UITextView *similarityView; //通过此标记判断选择图片要显示到哪一个相框上 @property (nonatomic,assign) NSInteger imageTag; @end @implementation YYFaceViewController - (void)viewDidLoad {
    [super viewDidLoad]; self.view.backgroundColor = [UIColor whiteColor];
    [self drawView];
}

- (void)drawView{ //创建两个按钮,点击事件为选择照片 UIButton *firstBtn = [UIButton buttonWithType:UIButtonTypeSystem];
    firstBtn.frame = CGRectMake(btnBorder, 100, (kwidth - btnBorder * 3)/2, 30);
    [firstBtn setTitle:@"setFirstPhoto" forState:UIControlStateNormal];
    [firstBtn addTarget:self action:@selector(selectFirstPhoto) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:firstBtn]; UIButton *secondBtn = [UIButton buttonWithType:UIButtonTypeSystem];
    secondBtn.frame = CGRectMake(CGRectGetMaxX(firstBtn.frame) + btnBorder, 100, (kwidth - btnBorder * 3)/2, 30);
    [secondBtn setTitle:@"setSecondPhoto" forState:UIControlStateNormal];
    [secondBtn addTarget:self action:@selector(selectSecondPhoto) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:secondBtn]; //创建两个相框,显示图片 UIImageView *firstImgV = [[UIImageView alloc]initWithFrame:CGRectMake(imgBorder, 140, (kwidth - imgBorder *3)/2, (kwidth - imgBorder *3)/2 *height / kwidth)];
    firstImgV.backgroundColor = [UIColor yellowColor];
    [self.view addSubview:firstImgV]; self.firstImgV = firstImgV; UIImageView *secondImgV = [[UIImageView alloc]initWithFrame:CGRectMake(CGRectGetMaxX(firstImgV.frame) + imgBorder, 140, (kwidth - imgBorder *3)/2, (kwidth - imgBorder *3)/2 *height / kwidth)];
    secondImgV.backgroundColor = [UIColor yellowColor];
    [self.view addSubview:secondImgV]; self.secondImgV = secondImgV; //相似度监测按钮 UIButton *recognizedBtn = [UIButton buttonWithType:UIButtonTypeSystem];
    recognizedBtn.frame = CGRectMake(self.view.bounds.size.width / 2, CGRectGetMaxY(secondImgV.frame) + 20, (kwidth - btnBorder * 3)/2, 30);
    recognizedBtn.center = CGPointMake(self.view.bounds.size.width / 2, CGRectGetMaxY(secondImgV.frame) + 20);
    [recognizedBtn setTitle:@"相似度计算(%)" forState:UIControlStateNormal];
    [recognizedBtn addTarget:self action:@selector(recognized) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:recognizedBtn];
    recognizedBtn.enabled = NO; self.recognizedBtn = recognizedBtn; //添加输入框显示输出信息 UITextView *similarityView = [[UITextView alloc]initWithFrame:CGRectMake((kwidth - 300) / 2, CGRectGetMaxY(recognizedBtn.frame) + 10, 300, 150)];
    similarityView.backgroundColor = [UIColor yellowColor];
    [self.view addSubview:similarityView]; self.similarityView = similarityView;


} //设置第一张图片 - (void)selectFirstPhoto{ self.imageTag = 999;
    [self alertController];
} //设置第二张图片 - (void)selectSecondPhoto{ self.imageTag = 888;
    [self alertController];
} //相似度监测 - (void)recognized{ //获取到两张面孔的face_id NSString *firstFace_id; NSData *firstImgVData = UIImageJPEGRepresentation(self.firstImgV.image, 0.6);
    FaceppResult *firstResult = [[FaceppAPI detection] detectWithURL:nil orImageData:firstImgVData]; NSArray *array1 = firstResult.content[@"face"]; if (array1.count == 1) {
        firstFace_id = [firstResult content][@"face"][0][@"face_id"];
    }else{ UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"提示" message:@"未检测到五官" delegate:self cancelButtonTitle:@"重新选择图片" otherButtonTitles: nil];
        [alert show]; return;
    } NSString *secondFace_id; NSData *secondImgVData = UIImageJPEGRepresentation(self.secondImgV.image, 0.6);
    FaceppResult *secondResult = [[FaceppAPI detection] detectWithURL:nil orImageData:secondImgVData]; NSArray *array2 = secondResult.content[@"face"]; if (array2.count == 1) {
        secondFace_id = [secondResult content][@"face"][0][@"face_id"];
    }else{ UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"提示" message:@"未检测到五官" delegate:self cancelButtonTitle:@"重新选择图片" otherButtonTitles: nil];
        [alert show]; return;

    } //比较二者的相似度 FaceppResult *similarResult = [[FaceppAPI recognition] compareWithFaceId1:firstFace_id andId2:secondFace_id async:NO]; if ([similarResult success]) { self.eye = [similarResult content][@"component_similarity"][@"eye"]; self.eyebrow = [similarResult content][@"component_similarity"][@"eyebrow"]; self.mouth = [similarResult content][@"component_similarity"][@"mouth"]; self.nose = [similarResult content][@"component_similarity"][@"nose"]; self.similarity = [similarResult content][@"similarity"]; NSString *content = [NSString stringWithFormat:@"眼睛:%@\n眉毛:%@\n嘴巴:%@\n鼻子:%@\n综合:%@",self.eye,self.eyebrow,self.mouth,self.nose,self.similarity]; self.similarityView.text = content;
    }else{ UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"提示" message:@"未检测到五官" delegate:self cancelButtonTitle:@"error" otherButtonTitles: nil];
        [alert show]; return;
    }



}

- (void)alertController{ UIAlertController * alertController = [UIAlertController alertControllerWithTitle:nil message:nil preferredStyle:UIAlertControllerStyleActionSheet]; //添加Button [alertController addAction: [UIAlertAction actionWithTitle: @"拍照" style: UIAlertActionStyleDefault handler:^(UIAlertAction *action) { //处理点击拍照 if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) { // 跳转到相机或相册页面 UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];
            imagePickerController.delegate = self;
            imagePickerController.allowsEditing = YES;
            [self presentViewController:imagePickerController animated:YES completion:^{}];
        }else{ UIAlertView *alert = [[UIAlertView alloc]initWithTitle:nil message:@"打开相机失败" delegate:self cancelButtonTitle:@"取消" otherButtonTitles: nil];
            [alert show];
        }

    }]];
    [alertController addAction: [UIAlertAction actionWithTitle: @"从相册选取" style: UIAlertActionStyleDefault handler:^(UIAlertAction *action){ //处理点击从相册选取 if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary]) { // 跳转到相机或相册页面 UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];

            imagePickerController.delegate = self;

            imagePickerController.allowsEditing = YES;


            [self presentViewController:imagePickerController animated:YES completion:^{}];
        }else{ UIAlertView *alert = [[UIAlertView alloc]initWithTitle:nil message:@"打开相机失败" delegate:self cancelButtonTitle:@"取消" otherButtonTitles: nil];
            [alert show];
        }
    }]];
    [alertController addAction: [UIAlertAction actionWithTitle: @"取消" style: UIAlertActionStyleCancel handler:nil]];
    [self presentViewController:alertController animated:YES completion:nil];
}

-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{
    [picker dismissViewControllerAnimated:YES completion:nil]; UIImage *image = [info objectForKey:UIImagePickerControllerOriginalImage]; if (self.imageTag == 999) { self.firstImgV.image = image;
    } if (self.imageTag == 888) { self.secondImgV.image = image;
    } if (self.firstImgV.image && self.secondImgV.image) { self.recognizedBtn.enabled = YES;
    }

}

-(void)imagePickerControllerDidCancel:(UIImagePickerController *)picker{
    [self dismissViewControllerAnimated:YES completion:nil];
}

-(void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated{


} @end

效果见下图:

文／yyMae（简书作者）
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