本人研究了两款OCR智能识别的API，下面做详解！
第一款是百度云的OCR识别，填写配置信息，每天有五百次免费的识别次数，适合中小型客户流量可以使用。API文档：http://ai.baidu.com/docs#/OCR-API/top
public static String Token = ""; // 调用getAccessToken()获取的 access_token建议根据expires_in 时间 设置缓存
private static String clientId = SysConfigManager.Get("bdy_config", "api_key");//"**********"; // 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 clientSecret = SysConfigManager.Get("bdy_config", "Secret_Key");//"***********"; /// <summary>
/// 获取百度云 access_token
/// </summary>
/// <returns></returns>
public static string GetbaiduAccessToken()
{
Token = Convert.ToString(HiCache.Get("access_token"));
if (string.IsNullOrEmpty(Token))
{
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; JObject ResObj = JsonHelper.DeserializeJsonToObject<JObject>(result);
if (string.IsNullOrEmpty(Convert.ToString(ResObj.GetValue("access_token"))))
{
Globals.Debuglog("---获取身份验证access_token失败:" + result, "_IdentifyCard.txt");
return Token;
}
HiCache.Insert("access_token", ResObj.GetValue("access_token"), ); //access_toke 时效30天，需设置缓存重新获取
Token = ResObj.GetValue("access_token").ToString();
}
return Token;
} /// <summary>
/// 根据access_token获取身份证信息
/// </summary>
/// <param name="path"></param>
/// <param name="cardside">身份证正反面(front-正面，back-反面)</param>
/// <param name="IsDelFile">是否删除图片</param>
/// <returns></returns>
public static string idcard(string path,string cardside,bool IsDelFile, out string outError)
{
outError = string.Empty;
string token = GetbaiduAccessToken();
if (!string.IsNullOrEmpty(token))
{
try
{
string ext = Path.GetExtension(path).ToLower(); ;
if (!ext.Equals(".jpg") && !ext.Equals(".png") && !ext.Equals(".bmp"))
{
outError = "识别的图片仅支持（jpg、png、bmp）格式";
return "";
}
string strbaser64 = Convert.ToBase64String(System.IO.File.ReadAllBytes(path));
string host = "https://aip.baidubce.com/rest/2.0/ocr/v1/idcard?access_token=" + token;
Encoding encoding = Encoding.Default;
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(host);
request.Method = "post";
request.ContentType = "application/x-www-form-urlencoded";
request.KeepAlive = true;
String str = "id_card_side="+ cardside + "&image=" + HttpUtility.UrlEncode(strbaser64);
byte[] buffer = encoding.GetBytes(str);
request.ContentLength = buffer.Length;
request.GetRequestStream().Write(buffer, , buffer.Length);
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.UTF8);
string result = reader.ReadToEnd();
string StrResult = Getcardinfo(result, cardside,out outError);
if (IsDelFile)
{
File.Delete(path);
}
return StrResult;
}
catch (Exception)
{
outError = "识别异常!";
File.Delete(path);
}
}
return ""; } /// <summary>
/// 对返回的身份信息进行打包确认
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
public static string Getcardinfo(string str,string cardside,out string outError)
{
outError = string.Empty;
JObject Obj = JsonHelper.DeserializeJsonToObject<JObject>(str);
string status = Convert.ToString(Obj.GetValue("image_status"));
string strResult = "";
if (status == "normal")
{
if (cardside == "front")
{
IdentifyInfo info = new IdentifyInfo();
info.Address = Obj["words_result"]["住址"]["words"].ToString();
info.DataBirth = Obj["words_result"]["出生"]["words"].ToString();
info.UserName = Obj["words_result"]["姓名"]["words"].ToString();
info.IdCard = Obj["words_result"]["公民身份号码"]["words"].ToString();
info.Sex = Obj["words_result"]["性别"]["words"].ToString();
info.FamousFamily = Obj["words_result"]["民族"]["words"].ToString();
strResult = JsonHelper.SerializeObject(info);
}
else
{ strResult = str; }
}
else
{
switch (status)
{
case "reversed_side":outError = "未摆正身份证!";break;
case "non_idcard": outError = "上传的图片不是身份证!"; break;
case "blurred": outError = "身份证模糊!"; break;
case "over_exposure": outError = "身份证关键字段反光或过曝!"; break;
default: outError = cardside == "front" ? "请正确上传身份证正面!": "请正确上传身份证背面!"; break;
}
}
return strResult;
}
/// <summary>
/// 创建临时地址文件
/// </summary>
/// <returns></returns>
private static string GetPath()
{
string path = "";
try
{
path = HttpContext.Current.Request.MapPath("~/Identify");
}
catch (Exception e)
{
path = Utils.ApplicationPath + "/Identify";
} if (!FileHelper.FileExists(path))
{
Directory.CreateDirectory(path);
}
path += "\\" + DateTime.Now.ToString("yyyyMMddHHmmss") + CommonHelper.RandomNum();
//if (!FileHelper.FileExists(path))
//{
// Directory.CreateDirectory(path);
//}
return path;
}
[Serializable]
public class IdentifyInfo
{
public string Address { get; set; } public string DataBirth { get; set; } public string UserName { get; set; } public string IdCard { get; set; } public string Sex { get; set; } //名族
public string FamousFamily { get; set; } }
第二款是祥云科技的OCR云服务平台，这里的识别更精确一点，但是消费有点贵。API文档：http://www.netocr.com/developers.do?id=4
/// <summary>
/// 上传图片到翔云进行身份证识别
/// </summary>
/// <param name="filePath">要上传的文件路径</param>
/// <returns></returns>
public string PostIdCardDataToXiangYun(string filePath)
{
string url = "http://netocr.com/api/recog.do";
System.Net.Http.HttpClient httpClient = new System.Net.Http.HttpClient();
httpClient.MaxResponseContentBufferSize = ;
httpClient.DefaultRequestHeaders.Add("user-agent", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/36.0.1985.143 Safari/537.36");
FileStream fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read);
System.Net.Http.MultipartFormDataContent content = new System.Net.Http.MultipartFormDataContent();
//增加文件数据
content.Add(new System.Net.Http.StreamContent(fileStream), "file", "idcard.jpg");
//增加参数
content.Add(new StringContent("key************"), "key");
content.Add(new StringContent("secret**********"), "secret");
//二代身份证正面识别
content.Add(new StringContent(CardStatus.TwoIdentityCardsFront.ToString()), "typeId");
content.Add(new StringContent("json"), "format");
System.Net.Http.HttpResponseMessage response = httpClient.PostAsync(new Uri(url), content).Result;
string result = response.Content.ReadAsStringAsync().Result;
fileStream.Close();
return result;
}