Java基于百度API的图片文字识别（支持中文，英文和中英文混合）

<!-- https://mvnrepository.com/artifact/com.alibaba/fastjson -->
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.46</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.httpcomponents/httpclient -->
<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpclient</artifactId>
    <version>4.5.5</version>
</dependency>

package com.wsk.netty.check;

import org.json.JSONObject;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.List;
import java.util.Map;
/**
 * 获取token类
 *
 * @Author : WuShukai
 * @Date :2018/2/12 10:04
 */

public class AuthService {

    /**
     * 获取权限token
     * @return 返回示例：
     * {
     * "access_token": "24.460da4889caad24cccdb1fea17221975.2592000.1491995545.282335-1234567",
     * "expires_in": 2592000
     * }
     */
    public static String getAuth() {
        // 官网获取的 API Key 更新为你注册的
        String clientId = "**";
        // 官网获取的 Secret Key 更新为你注册的
        String clientSecret = "**";
        return getAuth(clientId, clientSecret);
    }

    /**
     * 获取API访问token
     * 该token有一定的有效期，需要自行管理，当失效时需重新获取.
     * @param ak - 百度云官网获取的 API Key
     * @param sk - 百度云官网获取的 Securet Key
     * @return assess_token 示例：
     * "24.460da4889caad24cccdb1fea17221975.2592000.1491995545.282335-1234567"
     */
    private static String getAuth(String ak, String sk) {
        // 获取token地址
        String authHost = "https://aip.baidubce.com/oauth/2.0/token?";
        String getAccessTokenUrl = authHost
                // 1\. grant_type为固定参数
                + "grant_type=client_credentials"
                // 2\. 官网获取的 API Key
                + "&client_id=" + ak
                // 3\. 官网获取的 Secret Key
                + "&client_secret=" + sk;
        try {
            URL realUrl = new URL(getAccessTokenUrl);
            // 打开和URL之间的连接
            HttpURLConnection connection = (HttpURLConnection) realUrl.openConnection();
            connection.setRequestMethod("GET");
            connection.connect();
            // 获取所有响应头字段
            Map<String, List<String>> map = connection.getHeaderFields();
            // 遍历所有的响应头字段
            for (String key : map.keySet()) {
                System.err.println(key + "--->" + map.get(key));
            }
            // 定义 BufferedReader输入流来读取URL的响应
            BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
            StringBuilder result = new StringBuilder();
            String line;
            while ((line = in.readLine()) != null) {
                result.append(line);
            }
            /**
             * 返回结果示例
             */
            System.err.println("result:" + result);
            JSONObject jsonObject = new JSONObject(result.toString());
            return jsonObject.getString("access_token");
        } catch (Exception e) {
            System.err.printf("获取token失败！");
            e.printStackTrace(System.err);
        }
        return null;
    }

    public static void main(String[] args) {
        getAuth();
    }

}

package com.wsk.netty.check;

import sun.misc.BASE64Encoder;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URLEncoder;

/**
 * 图片转化base64后再UrlEncode结果
 * @Author : WuShukai
 * @Date :2018/2/12 10:43
 */

public class BaseImg64 {
    /**
     * 将一张本地图片转化成Base64字符串
     * @param imgPath 本地图片地址
     * @return 图片转化base64后再UrlEncode结果
     */
    public static String getImageStrFromPath(String imgPath) {
        InputStream in;
        byte[] data = null;
        // 读取图片字节数组
        try {
            in = new FileInputStream(imgPath);
            data = new byte[in.available()];
            in.read(data);
            in.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
        // 对字节数组Base64编码
        BASE64Encoder encoder = new BASE64Encoder();
        // 返回Base64编码过再URLEncode的字节数组字符串
        return URLEncoder.encode(encoder.encode(data));
    }
}

package com.wsk.netty.check;

import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;

import java.io.File;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;

/**
 * 图像文字识别
 *
 * @Author : WuShukai
 * @Date :2018/2/12 10:25
 */

public class Check {
    private static final String POST_URL = "https://aip.baidubce.com/rest/2.0/ocr/v1/general_basic?access_token=" + AuthService.getAuth();

    /**
     * 识别本地图片的文字
     *
     * @param path 本地图片地址
     * @return 识别结果，为json格式
     * @throws URISyntaxException URI打开异常
     * @throws IOException        io流异常
     */
    public static String checkFile(String path) throws URISyntaxException, IOException {
        File file = new File(path);
        if (!file.exists()) {
            throw new NullPointerException("图片不存在");
        }
        String image = BaseImg64.getImageStrFromPath(path);
        String param = "image=" + image;
        return post(param);
    }

    /**
     * @param url 图片url
     * @return 识别结果，为json格式
     */
    public static String checkUrl(String url) throws IOException, URISyntaxException {
        String param = "url=" + url;
        return post(param);
    }

    /**
     * 通过传递参数：url和image进行文字识别
     *
     * @param param 区分是url还是image识别
     * @return 识别结果
     * @throws URISyntaxException URI打开异常
     * @throws IOException        IO流异常
     */
    private static String post(String param) throws URISyntaxException, IOException {
        //开始搭建post请求
        HttpClient httpClient = new DefaultHttpClient();
        HttpPost post = new HttpPost();
        URI url = new URI(POST_URL);
        post.setURI(url);
        //设置请求头，请求头必须为application/x-www-form-urlencoded，因为是传递一个很长的字符串，不能分段发送
        post.setHeader("Content-Type", "application/x-www-form-urlencoded");
        StringEntity entity = new StringEntity(param);
        post.setEntity(entity);
        HttpResponse response = httpClient.execute(post);
        System.out.println(response.toString());
        if (response.getStatusLine().getStatusCode() == 200) {
            String str;
            try {
                /*读取服务器返回过来的json字符串数据*/
                str = EntityUtils.toString(response.getEntity());
                System.out.println(str);
                return str;
            } catch (Exception e) {
                e.printStackTrace();
                return null;
            }
        }
        return null;
    }

    public static void main(String[] args) {
        String path = "E:\\find.png";
        try {
            long now = System.currentTimeMillis();
            checkFile(path);
            checkUrl("https://gss3.bdstatic.com/-Po3dSag_xI4khGkpoWK1HF6hhy/baike/c0%3Dbaike80%2C5%2C5%2C80%2C26/sign=08c05c0e8444ebf8797c6c6db890bc4f/fc1f4134970a304e46bfc5f7d2c8a786c9175c19.jpg");
            System.out.println("耗时：" + (System.currentTimeMillis() - now) / 1000 + "s");
        } catch (URISyntaxException | IOException e) {
            e.printStackTrace();
        }
    }
}

作者：wsk1103
出处：https://blog.csdn.net/wsk1103/article/details/79316220