案例概述
本案例基于ASP.NET和百度云人脸库,主要实现静态人脸添加和静态人脸检测的功能,是笔者一个练习的小Demo
使用的工具
主要使用了VS 2017、MS SQL Server数据库和百度云人脸库
实现的功能
功能及代码展示
知识背景
百度人脸库的创建
1.打开浏览器登录百度智能云,(百度账号即可登录)
2.应用列表|创建应用
3.人脸库管理|选择刚刚创建好的应用
4.在这个应用中创建新分组(这个分组将在之后上传图片信息中用到)
本项目中用到的类
1.AccessToken.cs
主要功能:将创建人脸库时获取的API Key和Sercet Key,放入json字符串中传给百度云人脸识别接口,与自己创建的人脸库建立连接,并获取连接凭证。
返回回来的json字符串中含有的Access_Token就是这个凭证。
这个类不是笔者写的,是百度云提供的api调用方式文档(点此访问),在这个文档的基础上,笔者进行了一些修改,形成了下面的类。
using System;
using System.Collections.Generic;
using System.Net.Http;
using System.Web.Script.Serialization;
namespace com.baidu.ai
{
public static class AccessToken
{
// 调用getAccessToken()获取的 access_token建议根据expires_in 时间 设置缓存
// 返回token示例
public static String TOKEN = "24.adda70c11b9786206253ddb70affdc46.2592000.1493524354.282335-1234567";
// 百度云中开通对应服务应用的 API Key 建议开通应用的时候多选服务
private static String clientId = "*********";
// 百度云中开通对应服务应用的 Secret Key
private static String clientSecret = "**********";
public static String getAccessToken()
{
String authHost = "https://aip.baidubce.com/oauth/2.0/token";
HttpClient client = new HttpClient();
List<KeyValuePair<String, String>> paraList = new List<KeyValuePair<string, string>>();
paraList.Add(new KeyValuePair<string, string>("grant_type", "client_credentials"));
paraList.Add(new KeyValuePair<string, string>("client_id", clientId));
paraList.Add(new KeyValuePair<string, string>("client_secret", clientSecret));
HttpResponseMessage response = client.PostAsync(authHost, new FormUrlEncodedContent(paraList)).Result;
String result = response.Content.ReadAsStringAsync().Result;
Console.WriteLine(result);
//获取返回的字符串
//string test = AccessToken.getAccessToken();
//Response.Write(test + "
");
//获取返回的Access_Token
string Access_Token = "";
JavaScriptSerializer Jss = new JavaScriptSerializer();
Dictionary<string, object> DicText = (Dictionary<string, object>)Jss.DeserializeObject(result);
//如果返回值中含有access_token,则将其值赋予Access_Token,不存在则说明获取失败。
if (!DicText.ContainsKey("access_token"))
{
Access_Token = "获取Access_Token失败";
}
else
{
Access_Token = DicText["access_token"].ToString();
}
//Session["Token"] = Access_Token;
//Response.Write(Access_Token);
return Access_Token;
}
}
}
2.FaceAdd.cs
主要功能:在人脸库中新建人脸,并设置这个人脸的编号和分组,这个类也是基于百度云的开发文档
using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using System.Text;
using System.Web;
using System.Web.Script.Serialization;
namespace com.baidu.ai
{
public class FaceAdd
{
// 人脸注册
///参数说明:token->之前获取的Access_Token,base64->图片数据,tel->人脸编号
public static string add(string token,string base64,string tel)
{
//string token = "[调用鉴权接口获取的token]";
string host = "https://aip.baidubce.com/rest/2.0/face/v3/faceset/user/add?access_token=" + token;
Encoding encoding = Encoding.Default;
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(host);
request.Method = "post";
request.KeepAlive = true;
//将数据写入json字符串中
Dictionary<String, String> dic = new Dictionary<string, string>();
dic.Add("image", base64);
dic.Add("image_type", "BASE64");
//人脸库里的分组名
dic.Add("group_id", "Users");
//这个人脸的编号
dic.Add("user_id", tel);
//图片质量检测,Low表示可以接受较低画质的人脸数据
dic.Add("quality_control", "LOW");
//活体检测,这里只是一个小Demo,所以没有添加活体检测的功能
dic.Add("liveness_control", "NONE");
JavaScriptSerializer js = new JavaScriptSerializer();
String str = js.Serialize(dic);
byte[] buffer = encoding.GetBytes(str);
request.ContentLength = buffer.Length;
request.GetRequestStream().Write(buffer, 0, buffer.Length);
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.Default);
string result = reader.ReadToEnd();
Console.WriteLine("人脸注册:");
Console.WriteLine(result);
return result;
}
}
}
3.FaceSearch.cs
主要功能:将从前端获取的Base64格式的人脸图片信息和人脸库中已有的人脸进行对比,匹配的编号和匹配程度(百分制),参考百度云人脸搜索。
using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using System.Text;
using System.Web;
using System.Web.Script.Serialization;
namespace com.baidu.ai
{
public class FaceSearch
{
// 人脸搜索
public static string Search(string token, string strbase64)
{
//服务器地址,Access_Token作为凭证
string host = "https://aip.baidubce.com/rest/2.0/face/v3/search?access_token=" + token;
Encoding encoding = Encoding.Default;
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(host);
request.Method = "post";
request.KeepAlive = true;
//序列化,生成json字符串
Dictionary<String, String> dic = new Dictionary<string, string>();
dic.Add("image", strbase64);
dic.Add("image_type", "BASE64");
dic.Add("group_id_list", "Users");
dic.Add("quality_control", "LOW");
dic.Add("liveness_control", "NONE");
JavaScriptSerializer js = new JavaScriptSerializer();
String str = js.Serialize(dic);
byte[] buffer = encoding.GetBytes(str);
request.ContentLength = buffer.Length;
request.GetRequestStream().Write(buffer, 0, buffer.Length);
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.Default);
string result = reader.ReadToEnd();
Console.WriteLine("人脸搜索:");
Console.WriteLine(result);
return result;
}
}
}
主类其实就是上面三个类,但是为了方便从上面三个类返回的json字符串中取值和判断,笔者又添加了两个类
4.SearchReturn.cs
主要功能:实现json的反序列化,这个类文件中的几个类定义了一个数据类型,用于存放FaceSearch返回的json字符串转换成的变量。
其关系是 SearchReturn>Result>User_List
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
///
/// SearchReturn 的摘要说明
///
namespace com.baidu.ai
{
public class SearchReturn
{
public int error_code { get; set; }
public string error_msg { get; set; }
public long log_id { get; set; }
public int timestamp { get; set; }
public int cached { get; set; }
public Result result { get; set; }
}
public class Result
{
public string face_token { get; set; }
public User_List[] user_list { get; set; }
}
public class User_List
{
public string group_id { get; set; }
public string user_id { get; set; }
public string user_info { get; set; }
public float score { get; set; }
}
}
5.ReturnResultDetect.cs
主要功能:基于FaceAdd和FaceSearch返回的json字符串,获取相应的值并返回相应的标记以帮助业务代码的实现。
(*需要在Nuget中添加Newtonsoft包)
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Script.Serialization;
using Newtonsoft.Json.Linq;
using com.baidu.ai;
using Newtonsoft.Json;
///
/// ReturnResultDetect 的摘要说明
///
namespace com.baidu.ai
{
public static class ReturnResultDetect
{
public static int GetFaceAddReturnResult(string strjson)
{
int BackResult = 0;
SearchReturn feedback = JsonConvert.DeserializeObject<SearchReturn>(strjson);
if (feedback.result==null)
{
BackResult = 0;
}
else
{
BackResult = 1;
}
return BackResult;
}
public static string GetFaceSearchReturnResult(string strjson)
{
string BackResult ="";
int score = 0;
//将收到的json字符串转化成SearchReturn类型的变量,即反序列化
SearchReturn feedback = JsonConvert.DeserializeObject<SearchReturn>(strjson);
if (feedback.result==null)
{
BackResult = "_0"; //未检测到人脸
}
else
{
score = Convert.ToInt32(feedback.result.user_list[0].score);
if (score<80)
{
BackResult = "_1"; //人脸不匹配
}
else
{
BackResult = feedback.result.user_list[0].user_id;
}
}
return BackResult;
}
}
}
人脸注册
人脸注册的图像获取主要是通过HTML5的Video标签
和Canvas标签
,原理是将前置摄像头的视频内容放到video
中显示,然后通过点击按钮获取点击时刻的video
截图,将图片信息放入canvas
中保存,并且将图片内容编码为Base64再通过Hiddenfield
控件传给后端,实现后端对图片信息的获取。
前端代码
/*<%@ Page Language="C#" AutoEventWireup="true" CodeFile="User_Face_Signup.aspx.cs" Inherits="User_Face_Signup" %>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta charset='UTF-8' />
<meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0,user-scalable=no">
<title>人脸注册title>
<meta name="renderer" content="webkit">
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
<meta name="viewport" content="width=device-width,user-scalable=yes, minimum-scale=0.4, initial-scale=0.8,target-densitydpi=low-dpi" />
<link rel="stylesheet" href="./css/font.css">
<link rel="stylesheet" href="./css/xadmin.css">
<script type="text/javascript" src="https://cdn.bootcss.com/jquery/3.2.1/jquery.min.js">script>
<script type="text/javascript" src="./lib/layui/layui.js" charset="utf-8">script>
<script type="text/javascript" src="./js/xadmin.js">script>
<script type="text/javascript" src="./js/cookie.js">script>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
head>
<body>
<form id="form1" runat="server">
<div>
<div>
<%--<div>div>--%>
<div style="margin-top: 80px; margin-left: 20%; width: 30%; padding: 10px" class="layui-bg-green">人脸注册div>
<div style="margin-left: 20%; margin-top: 20px">
<video id="video" autoplay="" style="width: 70%;">video>
div>
<div style="margin-top: 10px; margin-left: 20%; width: 70%">
<asp:Label ID="Label1" runat="server" Text="Label">asp:Label>
div>
<div style="margin-top: 10px; margin-left: 20%; width: 30%">
<asp:Button ID="capture" runat="server" Text="提交并注册" OnClick="capture_Click" class="layui-btn" />
div>
<%--<div style="margin-left: 20%; width: 70%">
<span style="color: #f00; font-size: smaller">
<asp:Label ID="Label1" runat="server" Text="">asp:Label>
span>
div>--%>
div>
div>*/
<div>
<asp:HiddenField ID="HiddenField1" runat="server" />
div>
<div style="display: none">
<canvas id="canvas" width="480" height="320">canvas>
div>
<script type="text/javascript">
// 访问用户媒体设备的兼容方法
function getUserMedia(constraints, success, error) {
if (navigator.mediaDevices.getUserMedia) {
// 最新的标准API
navigator.mediaDevices.getUserMedia(constraints)
.then(success).catch(error);
} else if (navigator.webkitGetUserMedia) {
// Webkit核心浏览器
navigator.webkitGetUserMedia(constraints, success, error);
} else
if (navigator.mozGetUserMedia) {
// Firefox浏览器
navigator.mozGetUserMedia(constraints, success, error);
} else if (navigator.getUserMedia) {
// 旧版API
navigator.getUserMedia(constraints, success, error);
}
}
var video = document.getElementById("video");// video元素
var canvas = document.getElementById("canvas");// canvas元素
var context = canvas.getContext("2d");
// 成功的回调函数
function success(stream) {
var CompatibleURL = window.URL || window.webkitURL
video.src = CompatibleURL.createObjectURL(stream);//将视频流设置为video元素的源
video.play();// 播放视频
}
// 异常的回调函数
function error(error) {
console.log('访问用户媒体设备失败:', error.name, error.message);
}
if (navigator.mediaDevices.getUserMedia || navigator.getUserMedia ||
navigator.webkitGetUserMedia || navigator.mozGetUserMedia) {
// 调用用户媒体设备,访问摄像头
getUserMedia({ video: { width: 480, height: 320 } }, success, error);
} else {
alert('您的浏览器不支持访问用户媒体设备!');
}
// 绑定拍照按钮的点击事件
document.getElementById("capture").addEventListener("click", function () {
context.drawImage(video, 0, 0, 480, 320);
// 将video画面在canvas上绘制出来
var data = canvas.toDataURL('image/png', 1);
//将当前显示的图像传到Base64编码的字符串里
document.getElementById('HiddenField1').value = data;
//将上面转换好的Base64编码传到C#的HiddenField里,方便后端取值
});
script>
form>
body>
html>
后端代码
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using com.baidu.ai;
using System.Data;
using System.Data.Sql;
using System.Data.SqlClient;
public partial class User_Face_Signup : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
Label1.Text= "**请在光线充足的地方录入人脸以提高刷脸登录准确度!**
**准备好后点击下方按钮即可录入人脸!** ";
}
protected void capture_Click(object sender, EventArgs e)
{
//下面几个从session传过来的值是笔者这个项目里前一个页面的值,可以不看,但是为了保证程序完整性笔者还是将其放了上来
string name = Session["UserName"].ToString();
string tel = Session["UserTel"].ToString();
string password = Session["UserPass"].ToString();
string email = Session["UserMail"].ToString();
string PreBase64 = HiddenField1.Value;
string Base64 = "";
//兼容各种不同的图片格式
if (PreBase64.Contains("data:image/png;base64,"))
{
Base64 = PreBase64.Replace("data:image/png;base64,", "");
}
if(PreBase64.Contains("data:image/jpg; base64,"))
{
Base64 = PreBase64.Replace("data:image/jpg;base64,", "");
}
if (PreBase64.Contains("data:image/jpeg; base64,"))
{
Base64 = PreBase64.Replace("data:image/jpeg;base64,", "");
}
//调用类AccessToken中的getAccessToken方法,获取返回值Access_Token
//注:Access_Token其实每次取值都可以保留一段时间,但是为了减少不必要的麻烦,笔者这里还是每次都获取新的Access_Token,代价是每次都要多连接一次人脸库,浪费时间
string Access_Token = AccessToken.getAccessToken();
//将图片信息和对应人脸编号传入,上传到服务器
string Face_Add_Return = FaceAdd.add(Access_Token, Base64, tel);
//获取人脸添加的返回值,1表示添加成功,否则为失败
int Face_Add_Result = ReturnResultDetect.GetFaceAddReturnResult(Face_Add_Return);
if (Face_Add_Result==1)
{
SqlConnection conn = new SqlConnection();
conn.ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings["ConnectionStringProManage"].ConnectionString;
try
{
conn.Open();
string SQL = "insert into Users (uername,password,usertype,name,tel,email) values (@tel,@password,2,@name,@tel,@email)";
SqlCommand cmd = new SqlCommand();
cmd.Connection = conn;
cmd.CommandType = CommandType.Text;
cmd.CommandText = SQL;
//依次添加每个字段的值
SqlParameter ptel = new SqlParameter("@tel", SqlDbType.VarChar, 11);
ptel.Value = tel;
cmd.Parameters.Add(ptel);
SqlParameter ppassword = new SqlParameter("@password", SqlDbType.VarChar, 20);
ppassword.Value = password;
cmd.Parameters.Add(ppassword);
SqlParameter pname = new SqlParameter("@name", SqlDbType.NVarChar, 10);
pname.Value = name;
cmd.Parameters.Add(pname);
SqlParameter pemail = new SqlParameter("@email", SqlDbType.NVarChar, 30);
pemail.Value = email;
cmd.Parameters.Add(pemail);
int R = cmd.ExecuteNonQuery(); //R 的值就是返回影响表的行数
if (R > 0)
{
Session["ReturnPath"] = "Move_login.aspx";
Session["Message"] = "恭喜,注册成功!";
Response.Redirect("Success.aspx");
}
else
{
Session["Message"] = "插入失败,请检查您的操作!";
Response.Redirect("Error.aspx");
}
//Session["ReturnPath"] = "Admin_Add.aspx";
//Response.Redirect("Mid.aspx");
}
finally
{
conn.Close();
}
}
else
{
Label1.Text = "**未检测到人脸,请重试!** ";
}
}
}
人脸搜索
人脸搜索和人脸注册的实现方式是类似的,只不过一个是写(注册),一个是读(搜索)。注册是把人脸信息录入人脸库,并给其分配一个唯一标识号——人脸编号,而搜索就是一个相反的过程,通过上传的人脸与数据库中的人脸对比,返回这个人脸编号和相似度。
前端代码
<%--和人脸注册的代码基本一致-->
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="User_Face_Login.aspx.cs" Inherits="User_Face_Login" %>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta charset='UTF-8' />
<meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0,user-scalable=no"/>
<title>刷脸登录title>
<meta name="renderer" content="webkit"/>
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"/>
<meta name="viewport" content="width=device-width,user-scalable=yes, minimum-scale=0.4, initial-scale=0.8,target-densitydpi=low-dpi" />
<link rel="stylesheet" href="./css/font.css"/>
<link rel="stylesheet" href="./css/xadmin.css"/>
<script type="text/javascript" src="https://cdn.bootcss.com/jquery/3.2.1/jquery.min.js">script>
<script type="text/javascript" src="./lib/layui/layui.js" charset="utf-8">script>
<script type="text/javascript" src="./js/xadmin.js">script>
<script type="text/javascript" src="./js/cookie.js">script>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
head>
<body>
<form id="form1" runat="server">
<div>
<div>
<%--<div>div>--%>
<div style="margin-top: 80px; margin-left: 20%; width: 30%; padding: 10px" class="layui-bg-green">刷脸登录div>
<div style="margin-left: 20%; margin-top: 20px">
<video id="video" autoplay="" style="width: 70%;">video>
div>
<div style="margin-top: 10px; margin-left: 20%; width: 70%">
<asp:Label ID="Label1" runat="server" Text="">asp:Label>
div>
<div style="margin-top: 10px; margin-left: 20%; width: 30%">
<asp:Button ID="capture" runat="server" Text="登录" OnClick="capture_Click" class="layui-btn" />
div>
<%--<div style="margin-left: 20%; width: 70%">
<span style="color: #f00; font-size: smaller">
<asp:Label ID="Label1" runat="server" Text="">asp:Label>
span>
div>--%>
div>
div>
<div>
<asp:HiddenField ID="HiddenField1" runat="server" />
div>
<div style="display: none">
<canvas id="canvas" width="480" height="320">canvas>
div>
<script type="text/javascript">
// 访问用户媒体设备的兼容方法
function getUserMedia(constraints, success, error) {
if (navigator.mediaDevices.getUserMedia) {
// 最新的标准API
navigator.mediaDevices.getUserMedia(constraints)
.then(success).catch(error);
} else if (navigator.webkitGetUserMedia) {
// Webkit核心浏览器
navigator.webkitGetUserMedia(constraints, success, error);
} else
if (navigator.mozGetUserMedia) {
// Firefox浏览器
navigator.mozGetUserMedia(constraints, success, error);
} else if (navigator.getUserMedia) {
// 旧版API
navigator.getUserMedia(constraints, success, error);
}
}
var video = document.getElementById("video");// video元素
var canvas = document.getElementById("canvas");// canvas元素
var context = canvas.getContext("2d");
// 成功的回调函数
function success(stream) {
var CompatibleURL = window.URL || window.webkitURL
video.src = CompatibleURL.createObjectURL(stream);//将视频流设置为video元素的源
video.play();// 播放视频
}
// 异常的回调函数
function error(error) {
console.log('访问用户媒体设备失败:', error.name, error.message);
}
if (navigator.mediaDevices.getUserMedia || navigator.getUserMedia ||
navigator.webkitGetUserMedia || navigator.mozGetUserMedia) {
// 调用用户媒体设备,访问摄像头
getUserMedia({ video: { width: 480, height: 320 } }, success, error);
} else {
alert('您的浏览器不支持访问用户媒体设备!');
}
// 绑定拍照按钮的点击事件
document.getElementById("capture").addEventListener("click", function () {
context.drawImage(video, 0, 0, 480, 320);// 将video画面在canvas上绘制出来
var data = canvas.toDataURL('image/png', 1);
document.getElementById('HiddenField1').value = data;
});
script>
form>
body>
html>
后端代码
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using com.baidu.ai;
public partial class User_Face_Login : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
Label1.Text = "**请保持环境光线充足以提高刷脸登录准确度!**
**准备好后点击下方按钮即可登录!** ";
}
protected void capture_Click(object sender, EventArgs e)
{
//与上面类似的,获取前端传过来的Base64格式的图片编码
string PreBase64 = HiddenField1.Value;
string Base64 = "";
if (PreBase64.Contains("data:image/png;base64,"))
{
Base64 = PreBase64.Replace("data:image/png;base64,", "");
}
if (PreBase64.Contains("data:image/jpg; base64,"))
{
Base64 = PreBase64.Replace("data:image/jpg;base64,", "");
}
if (PreBase64.Contains("data:image/jpeg; base64,"))
{
Base64 = PreBase64.Replace("data:image/jpeg;base64,", "");
}
//获取Access_Token,同上
string Access_Token = AccessToken.getAccessToken();
//获取返回的json字符串
string feedback = FaceSearch.Search(Access_Token, Base64);
//从返回的字符串中取值,并根据值给出相应的判断
string backid = ReturnResultDetect.GetFaceSearchReturnResult(feedback);
if (backid=="_0")
{
Label1.Text = "**未检测到人脸,请重试!** ";
}
else if (backid == "_1")
{
Label1.Text = "**您尚未注册,请注册后登录** ";
Response.Redirect("Faca_Login_error.aspx");
}
else
{
Session["Move_Name"] = backid;
Session["Move_Islogin"] = 2;
Response.Redirect("Move_User.aspx");
}
}
}
本文是小弟在学习过程中做的一个小Demo,如有错误或者不当之处还请各位大佬斧正。
转载请注明原文链接。