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
@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:
333.png