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 ([e-mail])
 * @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。