基于java的百度语音识别示例

SDK以及示例代码下载地址： http://yuyin.baidu.com/sdk

最近一直在搞java，就选择了java工程。将代码拷过去。同时复制文件“test.pcm”到工程目录下。就基本上可以了。

注：test.pcm是语音文件，可以用audacity软件打开，选择 文件->导入->裸数据。 设置采样率为8000Hz。点击播放就能听见声音了。

这个时候程序跑起来还有问题，需要将apiKey 以及secretKey填写上。这两个值是你申请应用对应的分配好的。

cuid填本机mac地址就可以了，这个值我试过好像无所谓没啥要求。

程序能跑起来，并且按照正常返回识别的语音结果。但是返回结果的编码为GBK，所以汉字显示为乱码，需要对其进行一次转码。转码的代码是我自己加上去的。

下面贴代码：

package com.baidu.speech.serviceapi;

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLDecoder;
import java.net.URLEncoder;

import javax.xml.bind.DatatypeConverter;

import org.json.JSONObject;

public class Sample {

    private static final String serverURL = "http://vop.baidu.com/server_api";
    private static String token = "";
    private static final String testFileName = "test.pcm"; // 百度语音提供技术支持
    //put your own params here
    // 下面3个值要填写自己申请的app对应的值
    private static final String apiKey = "";
    private static final String secretKey = "";
    private static final String cuid = "";

    public static void main(String[] args) throws Exception {
        getToken();
        method1();
        method2();
    }

    private static void getToken() throws Exception {
        String getTokenURL = "https://openapi.baidu.com/oauth/2.0/token?grant_type=client_credentials" + 
            "&client_id=" + apiKey + "&client_secret=" + secretKey;
        HttpURLConnection conn = (HttpURLConnection) new URL(getTokenURL).openConnection();
        token = new JSONObject(printResponse(conn)).getString("access_token");
    }

    private static void method1() throws Exception {
        File pcmFile = new File(testFileName);
        HttpURLConnection conn = (HttpURLConnection) new URL(serverURL).openConnection();

        // construct params
        JSONObject params = new JSONObject();
        params.put("format", "pcm");
        params.put("rate", 8000);
        params.put("channel", "1");
        params.put("token", token);
        params.put("lan", "zh");
        params.put("cuid", cuid);
        params.put("len", pcmFile.length());
        params.put("speech", DatatypeConverter.printBase64Binary(loadFile(pcmFile)));

        // add request header
        conn.setRequestMethod("POST");
        conn.setRequestProperty("Content-Type", "application/json; charset=utf-8");

        conn.setDoInput(true);
        conn.setDoOutput(true);

        // send request
        DataOutputStream wr = new DataOutputStream(conn.getOutputStream());
        wr.writeBytes(params.toString());
        wr.flush();
        wr.close();

        printResponse(conn);
    }

    private static void method2() throws Exception {
        File pcmFile = new File(testFileName);
        HttpURLConnection conn = (HttpURLConnection) new URL(serverURL
                + "?cuid=" + cuid + "&token=" + token).openConnection();

        // add request header
        conn.setRequestMethod("POST");
        conn.setRequestProperty("Content-Type", "audio/pcm; rate=8000");

        conn.setDoInput(true);
        conn.setDoOutput(true);

        // send request
        DataOutputStream wr = new DataOutputStream(conn.getOutputStream());
        wr.write(loadFile(pcmFile));
        wr.flush();
        wr.close();

        System.out.println(getUtf8String(printResponse(conn)));
    }

    private static String printResponse(HttpURLConnection conn) throws Exception {
        if (conn.getResponseCode() != 200) {
            // request error
        	System.out.println("conn.getResponseCode() = " + conn.getResponseCode());
            return "";
        }
        InputStream is = conn.getInputStream();
        BufferedReader rd = new BufferedReader(new InputStreamReader(is));
        String line;
        StringBuffer response = new StringBuffer();
        while ((line = rd.readLine()) != null) {
            response.append(line);
            response.append('\r');
        }
        rd.close();
        System.out.println(new JSONObject(response.toString()).toString(4));
        return response.toString();
    }

    private static byte[] loadFile(File file) throws IOException {
        InputStream is = new FileInputStream(file);

        long length = file.length();
        byte[] bytes = new byte[(int) length];

        int offset = 0;
        int numRead = 0;
        while (offset < bytes.length
                && (numRead = is.read(bytes, offset, bytes.length - offset)) >= 0) {
            offset += numRead;
        }

        if (offset < bytes.length) {
            is.close();
            throw new IOException("Could not completely read file " + file.getName());
        }

        is.close();
        return bytes;
    }
    
    // GBK编码转为UTF-8
    private static String getUtf8String(String s) throws UnsupportedEncodingException
    {
    	StringBuffer sb = new StringBuffer();
    	sb.append(s);
    	String xmlString = "";
    	String xmlUtf8 = "";
		xmlString = new String(sb.toString().getBytes("GBK"));
		xmlUtf8 = URLEncoder.encode(xmlString , "GBK");
    	
    	return URLDecoder.decode(xmlUtf8, "UTF-8");
    }
}