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/* ----------------------------------------------------------
* 文件名称：BaiduFr.cs
* 作者：秦建辉
*
* 微信：splashcn
*
* 博客：http://www.firstsolver.com/wordpress/
*
* 开发环境：
* Visual Studio V2017
* .NET Framework 4
* Newtonsoft.Json 11.0.2
*
* 版本历史：
* V1.0 2018年03月27日
* 百度人脸检测类实现
------------------------------------------------------------ */
using Newtonsoft.Json.Linq;
using System;
using System.Collections.Generic;
using System.Drawing;
using System.IO;
using System.Net;
using System.Text;
namespace Com.FirstSolver.FR
{
public class BaiduFr : FrCore
{
/// <summary>
/// 厂家名称
/// </summary>
public override string Company { get { return "百度"; } }
/// <summary>
/// 应用标识
/// </summary>
private const string API_KEY = "Vnrv8o6lmHm3jAYsB62tZBod";
/// <summary>
/// 应用密钥
/// </summary>
private const string API_SECRET = "VmYQyST8kq3s0HcrGcdRHcLbxeGwNQDe";
/// <summary>
/// 访问授权码
/// </summary>
public string AccessToken { get; private set; }
/// <summary>
/// 人脸识别属性设置
/// </summary>
public Dictionary<string, string> RequestOptions = new Dictionary<string, string>{
{ "max_face_num", "5"},
{ "face_fields", "landmark" }
};
/// <summary>
/// 人脸识别接口初始化
/// </summary>
/// <returns>
/// 0-成功
/// 其它-失败
/// </returns>
public override int Initialize()
{
ErrorMessage = null;
// 获取授权码，授权服务地址：https://aip.baidubce.com/oauth/2.0/token
StringBuilder sb = new StringBuilder();
sb.Append("https://aip.baidubce.com/oauth/2.0/token?grant_type=client_credentials&client_id=").Append(API_KEY).Append("&client_secret=").Append(API_SECRET);
try
{
HttpWebRequest httpWebRequest = WebRequest.Create(sb.ToString()) as HttpWebRequest;
if (httpWebRequest == null) return -1;
using (HttpWebResponse response = httpWebRequest.GetResponse() as HttpWebResponse)
{
using (StreamReader sr = new StreamReader(response.GetResponseStream(), Encoding.UTF8))
{
AccessToken = JObject.Parse(sr.ReadToEnd())["access_token"].ToString();
return 0;
}
}
}
catch (Exception e)
{
ErrorMessage = e.Message;
return -2;
}
}
public override int Detect(byte[] image, out FFI[] faceset)
{
ErrorMessage = null;
faceset = null;
try
{
string options = CreateFaceDetectParameters(image);
var result = DoHttpPost("https://aip.baidubce.com/rest/2.0/face/v2/detect?access_token=" + AccessToken, options);
var error_code = result["error_code"];
if (error_code != null)
{
ErrorMessage = result["error_msg"].ToString();
return -1; // 人脸检测失败
}
else
{
JArray FaceJArray = result["result"] as JArray;
if (FaceJArray.Count == 0)
{
ErrorMessage = "未检测出人脸";
return -1; // 人脸检测失败
}
List<FFI> FaceCollection = new List<FFI>();
foreach (dynamic item in FaceJArray)
{
FFI face = new FFI();
// 显示人脸框及特征点
var location = item["location"];
face.Region = new Rectangle((int)location["left"], (int)location["top"], (int)location["width"], (int)location["height"]);
// 标记4个关键点
List<Point> CriticalPoints = new List<Point>();
foreach (dynamic point in item["landmark"])
{
CriticalPoints.Add(new Point((int)point["x"], (int)point["y"]));
}
face.CriticalPoints = CriticalPoints.ToArray();
// 标记72个特征点
List<Point> FeaturePoints = new List<Point>();
foreach (dynamic point in item["landmark72"])
{
FeaturePoints.Add(new Point((int)point["x"], (int)point["y"]));
}
face.FeaturePoints = FeaturePoints.ToArray();
FaceCollection.Add(face);
}
faceset = FaceCollection.ToArray();
return 0; // 成功
}
}
catch (System.Exception e)
{
ErrorMessage = e.Message;
return -2; // 异常
}
}
/// <summary>
/// 创建人脸检测调用参数
/// </summary>
/// <param name="image">图像数据</param>
/// <returns>人脸检测调用参数</returns>
private string CreateFaceDetectParameters(byte[] image)
{
StringBuilder sb = new StringBuilder();
foreach (KeyValuePair<string, string> item in RequestOptions)
{
if (!string.IsNullOrEmpty(item.Value))
{
sb.Append(item.Key).Append('=').Append(FrCore.UrlEncode(item.Value, Encoding.UTF8, false)).Append('&');
}
}
return sb.ToString() + "image=" + FrCore.UrlEncode(Convert.ToBase64String(image), Encoding.UTF8, false);
}
/// <summary>
/// 获取人脸检测结果
/// </summary>
/// <param name="url">人脸检测访问接口</param>
/// <param name="options">人脸检测参数</param>
/// <returns>人脸检测结果</returns>
public static JObject DoHttpPost(string url, string options)
{
HttpWebRequest httpWebRequest = WebRequest.Create(url) as HttpWebRequest;
if (httpWebRequest == null) return null;
httpWebRequest.Method = "POST";
httpWebRequest.KeepAlive = true;
httpWebRequest.ContentType = "application/x-www-form-urlencoded"; // 内容类型
byte[] Args = Encoding.UTF8.GetBytes(options);
httpWebRequest.ContentLength = Args.Length;
using (Stream requestStream = httpWebRequest.GetRequestStream())
{
requestStream.Write(Args, 0, Args.Length);
}
using (HttpWebResponse response = httpWebRequest.GetResponse() as HttpWebResponse)
{
using (StreamReader sr = new StreamReader(response.GetResponseStream(), Encoding.UTF8))
{
return JObject.Parse(sr.ReadToEnd());
}
}
}
}
}