一:简介
最近项目在做了身份证银行卡识别之后,开始实现人脸识别和活体识别,其中人脸识别包括人脸入库、人脸查找、人脸1:N对比、人脸N:N对比,另外活体识别运用在安全登录功能。
大家都熟知的支付宝使用face++ 的服务来实现人脸识别,在实际项目中使用了讯飞的人脸识别SDK进行二次封装来实现活体识别。主要实现了张嘴和摇头两个活体动作的识别。据我所知,讯飞的服务是基于face++,识别率还是很高,并且iOS和Android都对应有封装好的SDK。
在实际运用中,有很多app为了高度保证用户使用的安全问题,除了常规的账号密码登录之外,相继实现了指纹登录,手势登录,第三方登陆(QQ、微信、支付宝)、刷脸登录,接下里我就和大家分享一下如何实现人脸识别的活体检测,这是实现刷脸登录最基础的实现。
另外,这些博文都是来源于我日常开发中的技术总结,在时间允许的情况下,我会针对技术点分别分享iOS、Android两个版本,尽量附上demo以供大家参考,如果有其他技术点需要,可在文章后留言,我会尽全力帮助大家。
二:实现思路分析
点击识别按钮,调用相机
CameraRules类,检测相机权限
初始化页面,创建摄像页面,创建张嘴数据和摇头数据
开启识别,脸部框识别
脸部部位识别,脸部识别判断是否检测到人脸
检测到人脸之后,判断位置
位置判断合适,判断是否张嘴
张嘴判断完毕,验证是否摇头
摇头判断完毕,3秒倒计时拍照
拍照完毕,选择重拍或者上传图片
选择重拍重复5-9步骤,选择上传将图片数据回调
数据clean
三:实现源码分析
根据实现思路分析,一步步进行编码实现:
1. 点击识别按钮,调用相机
if([CameraRules isCapturePermissionGranted]){ [self setDeviceAuthorized:YES]; } else{ dispatch_async(dispatch_get_main_queue(), ^{ NSString* info=@"没有相机权限"; [self showAlert:info]; [self setDeviceAuthorized:NO]; }); }
2. CameraRules类,检测相机权限
//检测相机权限 +(BOOL)isCapturePermissionGranted{ if([AVCaptureDevice respondsToSelector:@selector(authorizationStatusForMediaType:)]){ AVAuthorizationStatus authStatus = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo]; if(authStatus ==AVAuthorizationStatusRestricted || authStatus ==AVAuthorizationStatusDenied){ return NO; } else if(authStatus==AVAuthorizationStatusNotDetermined){ dispatch_semaphore_t sema = dispatch_semaphore_create(0); __block BOOL isGranted=YES; [AVCaptureDevice requestAccessForMediaType:AVMediaTypeVideo completionHandler:^(BOOL granted) { isGranted=granted; dispatch_semaphore_signal(sema); }]; dispatch_semaphore_wait(sema, DISPATCH_TIME_FOREVER); return isGranted; } else{ return YES; } } else{ return YES; } }
3. 初始化页面,创建摄像页面,创建张嘴数据和摇头数据
//创建摄像页面,创建张嘴数据和摇头数据 [self faceUI]; [self faceCamera]; [self faceNumber];
4. 开启识别,脸部框识别
float cx = (left+right)/2; float cy = (top + bottom)/2; float w = right - left; float h = bottom - top; float ncx = cy ; float ncy = cx ; CGRect rectFace = CGRectMake(ncx-w/2 ,ncy-w/2 , w, h); if(!isFrontCamera){ rectFace=rSwap(rectFace); rectFace=rRotate90(rectFace, faceImg.height, faceImg.width); } BOOL isNotLocation = [self identifyYourFaceLeft:left right:right top:top bottom:bottom]; if (isNotLocation==YES) { return nil; }
5. 脸部部位识别,脸部识别判断是否检测到人脸
for(id key in keys){ id attr=[landmarkDic objectForKey:key]; if(attr && [attr isKindOfClass:[NSDictionary class]]){ if(!isFrontCamera){ p=pSwap(p); p=pRotate90(p, faceImg.height, faceImg.width); } if (isCrossBorder == YES) { [self delateNumber]; return nil; } p=pScale(p, widthScaleBy, heightScaleBy); [arrStrPoints addObject:NSStringFromCGPoint(p)]; } }
6. 检测到人脸之后,判断位置动作提醒
if (right - left < 230 || bottom - top < 250) { self.textLabel.text = @"太远了"; [self delateNumber]; isCrossBorder = YES; return YES; }else if (right - left > 320 || bottom - top > 320) { self.textLabel.text = @"太近了"; [self delateNumber]; isCrossBorder = YES; return YES; }else{ if (isJudgeMouth != YES) { self.textLabel.text = @"请重复张嘴动作"; [self tomAnimationWithName:@"openMouth" count:2]; if (left < 100 || top < 100 || right > 460 || bottom > 400) { isCrossBorder = YES; isJudgeMouth = NO; self.textLabel.text = @"调整下位置先"; [self delateNumber]; return YES; } }else if (isJudgeMouth == YES && isShakeHead != YES) { self.textLabel.text = @"请重复摇头动作"; [self tomAnimationWithName:@"shakeHead" count:4]; number = 0; }else{ takePhotoNumber += 1; if (takePhotoNumber == 2) { [self timeBegin]; } } isCrossBorder = NO; }
7. 位置判断合适,判断是否张嘴
if (rightX && leftX && upperY && lowerY && isJudgeMouth != YES) { number ++; if (number == 1 || number == 300 || number == 600 || number ==900) { mouthWidthF = rightX - leftX < 0 ? abs(rightX - leftX) : rightX - leftX; mouthHeightF = lowerY - upperY < 0 ? abs(lowerY - upperY) : lowerY - upperY; NSLog(@"%d,%d",mouthWidthF,mouthHeightF); }else if (number > 1200) { [self delateNumber]; [self tomAnimationWithName:@"openMouth" count:2]; } mouthWidth = rightX - leftX < 0 ? abs(rightX - leftX) : rightX - leftX; mouthHeight = lowerY - upperY < 0 ? abs(lowerY - upperY) : lowerY - upperY; NSLog(@"%d,%d",mouthWidth,mouthHeight); NSLog(@"张嘴前:width=%d,height=%d",mouthWidthF - mouthWidth,mouthHeight - mouthHeightF); if (mouthWidth && mouthWidthF) { 6 if (mouthHeight - mouthHeightF >= 20 && mouthWidthF - mouthWidth >= 15) { isJudgeMouth = YES; imgView.animationImages = nil; } } }
8. 张嘴判断完毕,验证是否摇头
if ([key isEqualToString:@"mouth_middle"] && isJudgeMouth == YES) { if (bigNumber == 0 ) { firstNumber = p.x; bigNumber = p.x; smallNumber = p.x; }else if (p.x > bigNumber) { bigNumber = p.x; }else if (p.x < smallNumber) { smallNumber = p.x; } if (bigNumber - smallNumber > 60) { isShakeHead = YES; [self delateNumber]; } }
9. 摇头判断完毕,3秒倒计时拍照
if(timeCount >= 1) { self.textLabel.text = [NSString stringWithFormat:@"%ld s后拍照",(long)timeCount]; } else { [theTimer invalidate]; theTimer=nil; [self didClickTakePhoto]; }
10. 拍照完毕,选择重拍或者上传图片
-(void)didClickPhotoAgain { [self delateNumber]; [self.previewLayer.session startRunning]; self.textLabel.text = @"请调整位置"; [backView removeFromSuperview]; isJudgeMouth = NO; isShakeHead = NO; }
11. 选择重拍重复5-9步骤,选择上传将图片数据回调
-(void)didClickUpPhoto { //上传照片成功 [self.faceDelegate sendFaceImage:imageView.image]; [self.navigationController popViewControllerAnimated:YES]; }
12. 数据clean
-(void)delateNumber { number = 0; takePhotoNumber = 0; mouthWidthF = 0; mouthHeightF = 0; mouthWidth = 0; mouthHeight = 0; smallNumber = 0; bigNumber = 0; firstNumber = 0; imgView.animationImages = nil; imgView.image = [UIImage imageNamed:@"shakeHead0"]; }
四:讯飞SDK下载及配置
1. SDK下载
因为项目中使用到讯飞人脸识别SDK,需要去讯飞开放平台创建应用,下载SDK。
2. 添加系统库
将开发工具包中lib目录下的iflyMSC.framework添加到工程中。同时请将Demo中依赖的其他库也添加到工程中。 按下图示例添加 SDK 所需要的 iOS系统库:
3. 设置Bitcode
在Targets - Build Settings 中搜索Bitcode 即可,找到相应选项,设置为NO,如下图:
4. 用户隐私权限配置
在Info.plist 中增加下图设置:
五:项目实际使用
1. 下载demo
下载demo,将demo中FBYFaceData文件夹引入项目中。
2. 在项目中引入FBYFaceRecognitionViewController
#import "FBYFaceRecognitionViewController.h"
3. 在项目识别按钮的点击事件中添加代码
-(void)pushToFaceStreamDetectorVC { FBYFaceRecognitionViewController *faceVC = [[FBYFaceRecognitionViewController alloc]init]; faceVC.faceDelegate = self; [self.navigationController pushViewController:faceVC animated:YES]; }
4. 图片回调函数
-(void)sendFaceImage:(UIImage *)faceImage { NSLog(@"图片上传成功"); } - (void)sendFaceImageError { NSLog(@"图片上传失败"); }
本篇文章demo源码:
希望可以帮助大家,如有问题可加QQ技术交流群: 668562416
如果哪里有什么不对或者不足的地方,还望读者多多提意见或建议
如需转载请联系我,经过授权方可转载,谢谢
本篇已同步到个人博客:FBY展菲
欢迎关注我的公众号:网罗开发