读取文件流并写入文件流

  Stream stream = File.OpenRead(Server.MapPath("0.jpg"));
          
        long len = stream.Length;
        byte[] buff = new byte[len];
        stream.Read(buff, 0, buff.Length);


        Stream f = new FileStream(Server.MapPath("1.jpg"), FileMode.OpenOrCreate);
        BinaryWriter write = new BinaryWriter(f);
        write.Write(buff, 0, buff.Length);

  using (Stream responseStream = response.GetResponseStream())
        {
            using (FileStream localFileStream =   new FileStream(Server.MapPath(path), FileMode.OpenOrCreate))
            {
                var buffer = new byte[1024];
             
                int bytesRead;

                while ((bytesRead = responseStream.Read(buffer, 0, buffer.Length)) > 0)
                { 
                    localFileStream.Write(buffer, 0, bytesRead);
                }
            }
        }

 下面代码，用于把其他网站的wav引起提取存放在本机，然后转换为pcm格式，然后提交到百度接口，最终把语音转换为文字。

参考 http://ai.baidu.com/docs#/ASR-API/top 介绍

    protected void Button1_Click(object sender, EventArgs e)
    {

         
       string  url = "http://localhost:50961/16.wav";
        string tempMedia=FetchMedia(url);  
        string pcmFile=ConvertMedia(tempMedia);

        var data = System.IO.File.ReadAllBytes(Server.MapPath(pcmFile));
        Asr _asrClient = new Asr("key", "key");
       
        // { "corpus_no": "6579488890526359184", "err_msg": "success.", "err_no": 0, "result": [ "今天中午吃什么呢我想吃回锅肉，不知道你喜欢不喜欢，" ], "sn": "87884864331531906633" }
 
        
        string json = _asrClient.Recognize(data, "pcm", 16000).ToString();


        BaiduResult r = Newtonsoft.Json.JsonConvert.DeserializeObject<BaiduResult>(json);
        Response.Write(r.result[0]);
      

        try
        {

            System.IO.File.Delete(Server.MapPath(tempMedia));
        }
        catch
        {
        }

        try
        {
            System.IO.File.Delete(Server.MapPath(pcmFile));

        }
        catch
        { }

    }


    public string FetchMedia(string fullURL)
    {
       
        HttpWebRequest request = WebRequest.Create(fullURL) as HttpWebRequest; 
        string filename = Guid.NewGuid().ToString() + ".wav";
        string path = "temp/" + filename; 

        using (HttpWebResponse response = request.GetResponse() as HttpWebResponse)
        { 
           using (Stream responseStream = response.GetResponseStream())
           {
               using (FileStream localFileStream = new FileStream(Server.MapPath(path), FileMode.OpenOrCreate))
               {
                var buffer = new byte[1024*10]; 
                int bytesRead;

                while ((bytesRead = responseStream.Read(buffer, 0, buffer.Length)) > 0)
                {
                    localFileStream.Write(buffer, 0, bytesRead);
                }
            }
          }
        } 

        return path;

    }




    public string ConvertMedia(string mediaName)
    {
        string exe = Server.MapPath("ffmpeg.exe");
        string fromFile = Server.MapPath(mediaName);
        string newFilename = "temp/" + Guid.NewGuid().ToString()+".pcm";
        string tofile = Server.MapPath(newFilename);
         
        //ffmpeg -y  -i 16k.wav  -acodec pcm_s16le -f s16le -ac 1 -ar 16000 16k.pcm 
        System.Diagnostics.Process p = System.Diagnostics.Process.Start(exe, " -y  -i ""+fromFile+""  -acodec pcm_s16le -f s16le -ac 1 -ar 16000 ""+tofile+"" ");
       // p.StartInfo.UseShellExecute = false;
        p.WaitForExit();
        return newFilename;
    }