access百度翻译 get_使用百度AI技术给黑白图像上色

{
	"log_id": "6876747463538438254",
	"image": "处理后图片的Base64编码"
}

        /// <summary>
        /// 获取百度access_token
        /// </summary>
        /// <param name="clientId">API Key</param>
        /// <param name="clientSecret">Secret Key</param>
        /// <returns></returns>
        public static string GetAccessToken(string clientId, string clientSecret)
        {
            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 jo = (JObject)JsonConvert.DeserializeObject(result);
            string token = jo["access_token"].ToString();
            return token;
        }

            string webRootPath = HostingEnvironment.WebRootPath;//wwwroot目录
 
            app.UseStaticFiles(new StaticFileOptions
            {
                FileProvider = new PhysicalFileProvider(
                    Path.Combine(webRootPath, "Uploads", "BaiduAIs")),
                RequestPath = "/BaiduAIs"
            });

    主要是一个form表单，需要设置属性enctype="multipart/form-data"，否则无法上传图片；
    form表单里面有两个控件：
    一个Input：type="file"，asp-for="FileUpload" ，上传图片用；
    一个Input：type="submit"，asp-page-handler="Colourize" ，提交并返回识别结果。
    一个img：src="@Model.curPath"，显示需要上色的图片。
    一个img：src="@Model.imgProcessPath"，显示上色后的图片。
    最后显示后台 msg 字符串列表信息，如果需要输出原始Html代码，则需要使用@Html.Raw()函数。

        [BindProperty]
        public IFormFile FileUpload { get; set; }
        private readonly IHostingEnvironment HostingEnvironment;
        public List<string> msg = new List<string>();
        public string curPath { get; set; }
        public string imgProcessPath { get; set; }
 
        public BodySearchModel(IHostingEnvironment hostingEnvironment)
        {
            HostingEnvironment = hostingEnvironment;
        }
 
        public async Task<IActionResult> OnPostColourizeAsync()
        {
            if (FileUpload is null)
            {
                ModelState.AddModelError(string.Empty, "本地图片！");
            }
            if (!ModelState.IsValid)
            {
                return Page();
            }
            msg = new List<string>();
 
            string webRootPath = HostingEnvironment.WebRootPath;//wwwroot目录
            string fileDir = Path.Combine(webRootPath, "Uploads//BaiduAIs//");
            string imgName = await UploadFile(FileUpload, fileDir);
 
            string fileName = Path.Combine(fileDir, imgName);
            string imgBase64 = GetFileBase64(fileName);
            curPath = Path.Combine("/BaiduAIs/", imgName);//需在Startup.cs 文件 的 Configure(IApplicationBuilder app, IHostingEnvironment env)方法中开启虚拟目录映射功能
 
            string result = GetImageProcessJson(imgBase64, “你的API KEY”, “你的SECRET KEY”);
            JObject jo =(JObject)JsonConvert.DeserializeObject(result);
            try
            {
                string imageProcessBase64 = jo["image"].ToString();
                msg.Add("log_id：" + jo["log_id"].ToString());
                string processImgName = Guid.NewGuid().ToString("N") + ".png";
                string imgSavedPath = Path.Combine(webRootPath, "Uploads//BaiduAIs//", processImgName);
                imgProcessPath = Path.Combine("/BaiduAIs/", processImgName);
                await GetFileFromBase64(imageProcessBase64, imgSavedPath);
            }
            catch(Exception e1)
            {
                msg.Add(result);
            }
            return Page();
        }
 
        /// <summary>
        /// 上传文件,返回文件名
        /// </summary>
        /// <param name="formFile">文件上传控件</param>
        /// <param name="fileDir">文件绝对路径</param>
        /// <returns></returns>
        public static async Task<string> UploadFile(IFormFile formFile, string fileDir)
        {
            if (!Directory.Exists(fileDir))
            {
                Directory.CreateDirectory(fileDir);
            }
            string extension = Path.GetExtension(formFile.FileName);
            string imgName = Guid.NewGuid().ToString("N") + extension;
            var filePath = Path.Combine(fileDir, imgName);
 
            using (var fileStream = new FileStream(filePath, FileMode.Create, FileAccess.Write))
            {
                await formFile.CopyToAsync(fileStream);
            }
 
            return imgName;
        }
 
 
        /// <summary>
        /// 返回图片的base64编码
        /// </summary>
        /// <param name="fileName">文件绝对路径名称</param>
        /// <returns></returns>
        public static String GetFileBase64(string fileName)
        {
            FileStream filestream = new FileStream(fileName, FileMode.Open);
            byte[] arr = new byte[filestream.Length];
            filestream.Read(arr, 0, (int)filestream.Length);
            string baser64 =  Convert.ToBase64String(arr);
            filestream.Close();
            return baser64;
        }
 
        /// <summary>
        /// 文件base64解码
        /// </summary>
        /// <param name="base64Str">文件base64编码</param>
        /// <param name="outPath">生成文件路径</param>
        public static async Task GetFileFromBase64(string base64Str, string outPath)
        {
            var contents = Convert.FromBase64String(base64Str);
            using (var fs = new FileStream(outPath, FileMode.Create, FileAccess.Write))
            {
                fs.Write(contents, 0, contents.Length);
                fs.Flush();
            }
        }
 
        /// <summary>
        /// 图像处理Json字符串
        /// </summary>
        /// <param name="strbaser64">图片base64编码</param>
        /// <param name="clientId">API Key</param>
        /// <param name="clientSecret">Secret Key</param>
        /// <returns></returns>
        public static string GetImageProcessJson(string strbaser64, string clientId, string clientSecret)
        {
            string token = GetAccessToken(clientId, clientSecret);
            string host = "https://aip.baidubce.com/rest/2.0/image-process/v1/colourize?access_token=" + token;
            Encoding encoding = Encoding.Default;
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(host);
            request.Method = "post";
            request.KeepAlive = true;
            string str = "image=" + HttpUtility.UrlEncode(strbaser64);
            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();
            return result;
        }