使用C#實現百度API【人臉檢測】V3版
阿新 • • 發佈：2019-02-10
第一次使用百度API C#程式（測試用）
最近實現
首先閱讀文件
第一步：註冊百度賬號獲取Access TOKEN
新增應用
得到Secret Key 和API Key
API Key 對應文件中的 clientId
SecretKey 對應文件中的 clientSecret
百度雲文件C#原始碼如下
using System; using System.Collections.Generic; using System.Net.Http; namespace com.baidu.ai { public static class AccessToken { // 呼叫getAccessToken()獲取的 access_token建議根據expires_in 時間 設定快取 // 返回token示例 public static String TOKEN = "24.adda70c11b9786206253ddb70affdc46.2592000.1493524354.282335-1234567"; // 百度雲中開通對應服務應用的 API Key 建議開通應用的時候多選服務 private static String clientId = "百度雲應用的AK"; // 百度雲中開通對應服務應用的 Secret Key private static String clientSecret = "百度雲應用的SK"; 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); return result; } } }
第二步：呼叫介面，獲取JSON資料
// 人臉檢測與屬性分析 public static string detect(String PictureBase64) { string token = AccessToken.getAccessToken(); string host = "https://aip.baidubce.com/rest/2.0/face/v3/detect?access_token=" + token; Encoding encoding = Encoding.Default; HttpWebRequest request = (HttpWebRequest)WebRequest.Create(host); request.Method = "post"; request.KeepAlive = true; String str = "{\"image\":\"" + PictureBase64 + "\",\"image_type\":\"BASE64\",\"face_field\":\"age,type\"}"; 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("人臉檢測與屬性分析:"); Console.WriteLine(result); return result; }
str是介面處理的資料，我image_type使用的是BASE64，face_field只返回了age和type的屬性，其他屬性參見文件自己新增
文件的str是這樣寫，根據自己需求可以替換新增
String str = "{\"image\":\"027d8308a2ec665acb1bdf63e513bcb9\",\"image_type\":\"FACE_TOKEN\",\"face_field\":\"faceshape,facetype\"}";例如我想直接飲用網上的圖片路徑（URL），則這樣寫
String str = "{\"image\":\"https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1533237885029&di=71c13d1cb749956107720a0c94f40876&imgtype=0&src=http%3A%2F%2Fimgsrc.baidu.com%2Fimgad%2Fpic%2Fitem%2F9a504fc2d56285358e6bf5d59aef76c6a6ef63be.jpg\",\"image_type\":\"URL\",\"face_field\":\"faceshape,facetype\"}";
使用BASE64型別的話要將圖片轉換成BASE64形式，然後呼叫介面。
第二步：JSON資料的解析
呼叫介面返回的是JSON資料，需要對JSON資料進行轉換。
下載開源的類庫Newtonsoft.Json(下載地址 http://json.codeplex.com/ )。
（或者直接在VS裡面下載）
定義類定義JSON資料，可以使用工具http://json2csharp.chahuo.com/
使用方法：將要處理的json字串複製到文字框即可以得到C#類，如圖所示：
解析JSON資料的程式碼如下:
private void button_change_Click(object sender, EventArgs e)
{
//解析JSON資料
RootObject people = JsonConvert.DeserializeObject<RootObject>(textBox_token.Text);
//獲取值
textBox_token.Text = "轉換結果：";
textBox_token.Text += people.error_msg + "\r\n" + "\r\n";
textBox_token.Text += "這是一張人臉的概率：";
textBox_token.Text += people.result.face_list[0].face_probability + "\r\n" + "\r\n";
textBox_token.Text += "年齡：";
textBox_token.Text += people.result.face_list[0].age + "\r\n" + "\r\n";
textBox_token.Text += "顏值：";
textBox_token.Text += people.result.face_list[0].beauty + "\r\n" + "\r\n";
textBox_token.Text += "表情：";
textBox_token.Text += people.result.face_list[0].expression.probability + "概率是";
string expression_type = people.result.face_list[0].expression.type;
if(expression_type == "none") { expression_type = "冷漠臉"; }
else if(expression_type == "smile") { expression_type = "微笑"; }
else if (expression_type == "laugh") { expression_type = "大笑"; }
else { expression_type = "都不知道你什麼表情"; }
textBox_token.Text += expression_type + "\r\n" + "\r\n";
//square: 正方形 triangle:三角形 oval: 橢圓 heart: 心形 round: 圓形
textBox_token.Text += "臉型：";
textBox_token.Text += people.result.face_list[0].face_shape.probability + "概率是";
string faceShape = people.result.face_list[0].face_shape.type;
if (faceShape == "square") { faceShape = "正方形"; }
else if (faceShape == "triangle") { faceShape = "三角形"; }
else if (faceShape == "oval") { faceShape = "橢圓"; }
else if (faceShape == "heart") { faceShape = "心形"; }
else if (faceShape == "round") { faceShape = "圓形"; }
else { faceShape = "都不知道你什麼頭"; }
textBox_token.Text += faceShape + "\r\n" + "\r\n";
//male:男性 female:女性
textBox_token.Text += "性別：";
textBox_token.Text += people.result.face_list[0].gender.probability + "概率是";
string sex = people.result.face_list[0].gender.type;
if (sex == "male") { sex = "男性"; }
else if (sex == "female") { sex = "女性"; }
else { sex = "都不知道你什麼性別"; }
textBox_token.Text += sex + "\r\n" + "\r\n";
//none:無眼鏡，common:普通眼鏡，sun:墨鏡
textBox_token.Text += "眼鏡型別：";
textBox_token.Text += people.result.face_list[0].glasses.probability + "概率是";
string glasse = people.result.face_list[0].glasses.type;
if (glasse == "none") { glasse = "無眼鏡"; }
else if (glasse == "common") { glasse = "普通眼鏡"; }
else if (glasse == "sun") { glasse = "墨鏡"; }
else { faceShape = "眼呢？"; }
textBox_token.Text += glasse + "\r\n" + "\r\n";
//yellow: 黃種人 white: 白種人 black:黑種人 arabs: 阿拉伯人
textBox_token.Text += "種族：";
textBox_token.Text += people.result.face_list[0].race.probability + "概率是";
string race = people.result.face_list[0].race.type;
if (race == "yellow") { race = "黃種人"; }
else if (race == "white") { race = "白種人"; }
else if (race == "black") { race = "黑種人"; }
else if (race == "arabs") { race = "阿拉伯人"; }
else { race = "人呢？"; }
textBox_token.Text += race + "\r\n" + "\r\n";
}
}