java实现腾讯ocr图片识别接口调用

最近开发了一个拍车牌识别车牌号的功能，主要调用了腾讯的ocr车牌识别接口，直接上代码：

首先生成签名以及读取配置的工具类：

package com.weaver.formmodel.integration.ocr;

import java.util.Random;
import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import weaver.general.Base64;

public class SignUtil {
 /**
 * 生成 Authorization 签名字段
 *
 * @param appId
 * @param secretId
 * @param secretKey
 * @param bucketName
 * @param expired
 * @return 签名字符串
 * @throws Exception
 */
 public static String appSign(long appId, String secretId, String secretKey,
  String bucketName, long expired) throws Exception {
 long now = System.currentTimeMillis() / 1000;
 int rdm = Math.abs(new Random().nextInt());
 String plainText = String.format("a=%d&b=%s&k=%s&t=%d&e=%d&r=%d",
  appId, bucketName, secretId, now, now + expired, rdm);
 byte[] hmacDigest = HmacSha1(plainText, secretKey);
 byte[] signContent = new byte[hmacDigest.length
  + plainText.getBytes().length];
 System.arraycopy(hmacDigest, 0, signContent, 0, hmacDigest.length);
 System.arraycopy(plainText.getBytes(), 0, signContent,
  hmacDigest.length, plainText.getBytes().length);
 return Base64Encode(signContent);
 }

 /**
 * 生成 base64 编码
 *
 * @param binaryData
 * @return
 */
 public static String Base64Encode(byte[] binaryData) {
 String encodedstr = new String(Base64.encode(binaryData));
 return encodedstr;
 }

 /**
 * 生成 hmacsha1 签名
 *
 * @param binaryData
 * @param key
 * @return
 * @throws Exception
 */
 public static byte[] HmacSha1(byte[] binaryData, String key)
  throws Exception {
 Mac mac = Mac.getInstance("HmacSHA1");
 SecretKeySpec secretKey = new SecretKeySpec(key.getBytes(), "HmacSHA1");
 mac.init(secretKey);
 byte[] HmacSha1Digest = mac.doFinal(binaryData);
 return HmacSha1Digest;
 }

 /**
 * 生成 hmacsha1 签名
 *
 * @param plainText
 * @param key
 * @return
 * @throws Exception
 */
 public static byte[] HmacSha1(String plainText, String key)
  throws Exception {
 return HmacSha1(plainText.getBytes(), key);
 }
}

package weaver.general;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.ByteArrayOutputStream;
import java.io.CharArrayWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.Reader;
import java.io.Writer;

/**
 * Provides encoding of raw bytes to base64-encoded characters, and decoding of
 * base64 characters to raw bytes. date: 06 August 1998 modified: 14 February
 * 2000 modified: 22 September 2000
 *
 * @author Kevin Kelley (kelley@ruralnet.net)
 * @version 1.3
 */
public class Base64 {

 /**
 * returns an array of base64-encoded characters to represent the passed
 * data array.
 *
 * @param data
 *      the array of bytes to encode
 * @return base64-coded character array.
 */
 public static char[] encode(byte[] data) {
 char[] out = new char[((data.length + 2) / 3) * 4];

 //
 // 3 bytes encode to 4 chars. Output is always an even
 // multiple of 4 characters.
 //
 for (int i = 0, index = 0; i < data.length; i += 3, index += 4) {
  boolean quad = false;
  boolean trip = false;

  int val = (0xFF & data[i]);
  val <<= 8;
  if ((i + 1) < data.length) {
  val |= (0xFF & data[i + 1]);
  trip = true;
  }
  val <<= 8;
  if ((i + 2) < data.length) {
  val |= (0xFF & data[i + 2]);
  quad = true;
  }
  out[index + 3] = alphabet[(quad ? (val & 0x3F) : 64)];
  val >>= 6;
  out[index + 2] = alphabet[(trip ? (val & 0x3F) : 64)];
  val >>= 6;
  out[index + 1] = alphabet[val & 0x3F];
  val >>= 6;
  out[index + 0] = alphabet[val & 0x3F];
 }
 return out;
 }

 /**
 * Decodes a BASE-64 encoded stream to recover the original data. White
 * space before and after will be trimmed away, but no other manipulation of
 * the input will be performed.
 *
 * As of version 1.2 this method will properly handle input containing junk
 * characters (newlines and the like) rather than throwing an error. It does
 * this by pre-parsing the input and generating from that a count of VALID
 * input characters.
 **/
 public static byte[] decode(char[] data) {
 // as our input could contain non-BASE64 data (newlines,
 // whitespace of any sort, whatever) we must first adjust
 // our count of USABLE data so that...
 // (a) we don't misallocate the output array, and
 // (b) think that we miscalculated our data length
 // just because of extraneous throw-away junk

 int tempLen = data.length;
 for (int ix = 0; ix < data.length; ix++) {
  if ((data[ix] > 255) || codes[data[ix]] < 0)
  --tempLen; // ignore non-valid chars and padding
 }
 // calculate required length:
 // -- 3 bytes for every 4 valid base64 chars
 // -- plus 2 bytes if there are 3 extra base64 chars,
 // or plus 1 byte if there are 2 extra.

 int len = (tempLen / 4) * 3;
 if ((tempLen % 4) == 3)
  len += 2;
 if ((tempLen % 4) == 2)
  len += 1;

 byte[] out = new byte[len];

 int shift = 0; // # of excess bits stored in accum
 int accum = 0; // excess bits
 int index = 0;

 // we now go through the entire array (NOT using the 'tempLen' value)
 for (int ix = 0; ix < data.length; ix++) {
  int value = (data[ix] > 255) ? -1 : codes[data[ix]];

  if (value >= 0)// skip over non-code
  {
  accum <<= 6; // bits shift up by 6 each time thru
  shift += 6; // loop, with new bits being put in
  accum |= value; // at the bottom.
  if (shift >= 8)// whenever there are 8 or more shifted in,
  {
   shift -= 8; // write them out (from the top, leaving any
   out[index++] = // excess at the bottom for next iteration.
   (byte) ((accum >> shift) & 0xff);
  }
  }
  // we will also have skipped processing a padding null byte ('=')
  // here;
  // these are used ONLY for padding to an even length and do not
  // legally
  // occur as encoded data. for this reason we can ignore the fact
  // that
  // no index++ operation occurs in that special case: the out[] array
  // is
  // initialized to all-zero bytes to start with and that works to our
  // advantage in this combination.
 }

 // if there is STILL something wrong we just have to throw up now!
 if (index != out.length) {
  throw new Error("Miscalculated data length (wrote " + index
   + " instead of " + out.length + ")");
 }

 return out;
 }

 //
 // code characters for values 0..63
 //
 private static char[] alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/="
  .toCharArray();

 //
 // lookup table for converting base64 characters to value in range 0..63
 //
 private static byte[] codes = new byte[256];

 static {
 for (int i = 0; i < 256; i++)
  codes[i] = -1;
 for (int i = 'A'; i <= 'Z'; i++)
  codes[i] = (byte) (i - 'A');
 for (int i = 'a'; i <= 'z'; i++)
  codes[i] = (byte) (26 + i - 'a');
 for (int i = '0'; i <= '9'; i++)
  codes[i] = (byte) (52 + i - '0');
 codes['+'] = 62;
 codes['/'] = 63;
 }

 // /////////////////////////////////////////////////
 // remainder (main method and helper functions) is
 // for testing purposes only, feel free to clip it.
 // /////////////////////////////////////////////////

 public static void main(String[] args) {
 boolean decode = false;

 if (args.length == 0) {
  System.out.println("usage: java Base64 [-d[ecode]] filename");
  System.exit(0);
 }
 for (int i = 0; i < args.length; i++) {
  if ("-decode".equalsIgnoreCase(args[i]))
  decode = true;
  else if ("-d".equalsIgnoreCase(args[i]))
  decode = true;
 }

 String filename = args[args.length - 1];
 File file = new File(filename);
 if (!file.exists()) {
  System.out
   .println("Error: file '" + filename + "' doesn't exist!");
  System.exit(0);
 }

 if (decode) {
  char[] encoded = readChars(file);
  byte[] decoded = decode(encoded);
  writeBytes(file, decoded);
 } else {
  byte[] decoded = readBytes(file);
  char[] encoded = encode(decoded);
  writeChars(file, encoded);
 }
 }

 private static byte[] readBytes(File file) {
 ByteArrayOutputStream baos = new ByteArrayOutputStream();
 try {
  InputStream fis = new FileInputStream(file);
  InputStream is = new BufferedInputStream(fis);
  int count = 0;
  byte[] buf = new byte[16384];
  while ((count = is.read(buf)) != -1) {
  if (count > 0)
   baos.write(buf, 0, count);
  }
  is.close();
 } catch (Exception e) {
  e.printStackTrace();
 }

 return baos.toByteArray();
 }

 private static char[] readChars(File file) {
 CharArrayWriter caw = new CharArrayWriter();
 try {
  Reader fr = new FileReader(file);
  Reader in = new BufferedReader(fr);
  int count = 0;
  char[] buf = new char[16384];
  while ((count = in.read(buf)) != -1) {
  if (count > 0)
   caw.write(buf, 0, count);
  }
  in.close();
 } catch (Exception e) {
  e.printStackTrace();
 }

 return caw.toCharArray();
 }

 private static void writeBytes(File file, byte[] data) {
 try {
  OutputStream fos = new FileOutputStream(file);
  OutputStream os = new BufferedOutputStream(fos);
  os.write(data);
  os.close();
 } catch (Exception e) {
  e.printStackTrace();
 }
 }

 private static void writeChars(File file, char[] data) {
 try {
  Writer fos = new FileWriter(file);
  Writer os = new BufferedWriter(fos);
  os.write(data);
  os.close();
 } catch (Exception e) {
  e.printStackTrace();
 }
 }
 // /////////////////////////////////////////////////
 // end of test code.
 // /////////////////////////////////////////////////

}

package weaver.general;

import java.io.File;
import java.io.FileInputStream;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;

public class BaseBean {
 private static Map<String, Properties> propertyMap = new HashMap<String, Properties>();

 public String getPropValue(String cONFIG_FILE, String key) {
 if (propertyMap.get(cONFIG_FILE) == null) {
  readPro(cONFIG_FILE);
 }
 Properties pro = propertyMap.get(cONFIG_FILE);
 return pro.getProperty(key);
 }

 private void readPro(String cONFIG_FILE) {
 Properties pro = new Properties();
 FileInputStream in;
 try {
  String path = Thread.currentThread().getContextClassLoader()
   .getResource("").toString();
  path = path.substring(6, path.indexOf("classes/"));
  path = path + "prop/" + cONFIG_FILE + ".properties";
  path = path.replace("%20", " ");
  System.out.println(path);
  File f = new File(path);
  if (!f.exists()) {
  throw new RuntimeException("要读取的文件不存在");
  }
  in = new FileInputStream(f);
  pro.load(in);
  in.close();
  propertyMap.put(cONFIG_FILE, pro);
 } catch (Exception e) {
  e.printStackTrace();
 }

 }

}

package weaver.general;

public class Util {

 public static int getIntValue(String value) {
 try {
  return Integer.parseInt(value);
 } catch (NumberFormatException e) {
  e.printStackTrace();
  return 0;
 }

 }

}

然后是接口调配置文件：

正主来了，调用接口部分：

package com.weaver.formmodel.integration.ocr;

import java.util.HashMap;
import java.util.Map;
import net.sf.json.JSONObject;
import org.apache.commons.httpclient.HttpStatus;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.StatusLine;
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.params.CoreConnectionPNames;
import org.apache.http.util.EntityUtils;
import weaver.general.BaseBean;
import weaver.general.Util;
public class OCRClient{
 private static String CONFIG_FILE = "OCR_Tencent";
 private static String host;
 private static int appid;
 private static String secretId;
 private static String secretKey;
 private static String targeturl;
 private static String encoding = "UTF-8";

 static {
 BaseBean bb = new BaseBean();
 host = bb.getPropValue(CONFIG_FILE, "host");
 appid = Util.getIntValue(bb.getPropValue(CONFIG_FILE, "appid"));
 secretId = bb.getPropValue(CONFIG_FILE, "secretId");
 secretKey = bb.getPropValue(CONFIG_FILE, "secretKey");
 targeturl = bb.getPropValue(CONFIG_FILE, "targetUrl");

 }

 /**
 * 识别图片
 * @param imageurl
 * @param paramsMap 参数map
 * @return
 * @throws Exception
 */
 public static Map<String, Object> recognizeImage(Map<String,Object> paramsMap) throws Exception{
 HttpClient httpclient = new DefaultHttpClient();
 HttpPost httpPost = new HttpPost(targeturl);// 创建httpPost
 httpPost.setHeader("host", host);
 //设置签名
    httpPost.setHeader("Authorization", SignUtil.appSign(appid, secretId, secretKey, "", 2592000));//设置请求头, 签名
    //设置参数
 JSONObject requestParam = new JSONObject();
 requestParam.put("appid", String.valueOf(appid));
 for(String key :paramsMap.keySet()){//循环加入请求参数
  requestParam.put(key, paramsMap.get(key));
 }
 //请求报文
    StringEntity entity = new StringEntity(requestParam.toString(), encoding);
    entity.setContentEncoding(encoding);
    entity.setContentType("application/json");//发送json数据需要设置contentType
    httpPost.setEntity(entity);
    httpPost.getParams().setParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, 120000);
    httpPost.getParams().setParameter(CoreConnectionPNames.SO_TIMEOUT, 120000);
    int state = 0;
    String result = "";
    HttpResponse response = null;
    try {
     response = httpclient.execute(httpPost);
      StatusLine status = response.getStatusLine();
      state = status.getStatusCode();
      if (state == HttpStatus.SC_OK) {
       HttpEntity responseEntity = response.getEntity();
       result = EntityUtils.toString(responseEntity);
      }else{
  //new BaseBean().writeLog("读取OCR驾驶证或者行驶证接口失败，状态码:"+state);
  }
    } finally {
     httpclient.getConnectionManager().shutdown();
    }
    Map<String, Object> resultMap = new HashMap<String, Object>();
    resultMap.put("state", state);
    resultMap.put("result", result);
    return resultMap;
 }

 //测试
 public static void main(String[] args) {
 String imgurl = "https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1532414063478&di=f8709d73023a1a4ef9fe58f23ec95a8e&imgtype=jpg&src=http%3A%2F%2Fimg3.imgtn.bdimg.com%2Fit%2Fu%3D2587099383%2C4041264664%26fm%3D214%26gp%3D0.jpg";
 try {
  //车牌号识别参数设置
  Map<String, Object> requestParam = new HashMap<String, Object>();
  requestParam.put("url", imgurl);
  Map<String,Object> res =recognizeImage(requestParam);
  //解析车牌号返回值
  JSONObject resultJson = JSONObject.fromObject(res.get("result"));
  System.out.println(resultJson.toString());
 } catch (Exception e) {
  e.printStackTrace();
 }
 }
}

如需调用其他接口，如身份证识别接口、驾驶证识别接口、等，则只需要修改一下配置文件的targeturl，并且调用时传入相应的参数即可。

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持我们。