先导库
implementation 'com.rmtheis:tess-two:9.0.0'
9.0.0是目前最新的，https://github.com/rmtheis/tess-two可以去这个地方查看最新地址。
既然是图片识别，那一想就可知，需要传入一个图片bitmap，那么返回的肯定是图片中的内容String。
TessBaseAPI tessBaseAPI = new TessBaseAPI();
tessBaseAPI.init(DATAPATH, DEFAULT_LANGUAGE);
tessBaseAPI.setImage(bitmap);
String text = tessBaseAPI.getUTF8Text();
3行代码，就这么简单。单身么，先new个TessBaseAPI对象。 初始化。DATAPATH 和
DEFAULT_LANGUAGE如下 private static final String DATAPATH = Environment.getExternalStorageDirectory().getAbsolutePath() + File.separator;
private static final String DEFAULT_LANGUAGE = "chi_sim";
然后呢，就做这些肯定是会报错的。我就踩了这个坑。SD卡权限。别忘了加。
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" /> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
6.0以上动态申请权限。你懂的。自己百度去吧。
然后有个copyToSD方法是将assets中的识别库复制到SD卡中。待会贴上完整代码。
assets目录下需要的文件在这里，自己去下。
https://github.com/tesseract-ocr/tessdata
有很多，我目前只用了
chi_sim.traineddata
eng.traineddata
hebing.traineddata
nor.traineddata
normal.traineddata
这5个，你可以根据需要加到assets下
第三个方法就是设置一个bitmap进去了，然后 tessBaseAPI.getUTF8Text();就可以获取读取到的内容了。非常简单。 贴上完整代码
public class Main2Activity extends AppCompatActivity implements View.OnClickListener{
private static final String TAG = "Main2Activity";
private Button btn;
private TextView tv;
private ImageView cropView;
/**
* TessBaseAPI初始化用到的第一个参数，是个目录。
*/
private static final String DATAPATH = Environment.getExternalStorageDirectory().getAbsolutePath() + File.separator;
/**
* 在DATAPATH中新建这个目录，TessBaseAPI初始化要求必须有这个目录。
*/
private static final String tessdata = DATAPATH + File.separator + "tessdata";
/**
* TessBaseAPI初始化测第二个参数，就是识别库的名字不要后缀名。
*/
private static final String DEFAULT_LANGUAGE = "chi_sim";
/**
* assets中的文件名
*/
private static final String DEFAULT_LANGUAGE_NAME = DEFAULT_LANGUAGE + ".traineddata";
/**
* 保存到SD卡中的完整文件名
*/
private static final String LANGUAGE_PATH = tessdata + File.separator + DEFAULT_LANGUAGE_NAME;
/**
* 权限请求值
*/
private static final int PERMISSION_REQUEST_CODE=0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
btn = (Button) findViewById(R.id.btn);
tv = (TextView) findViewById(R.id.tv);
cropView = (ImageView) findViewById(R.id.iv);
Log.d("dddd",DATAPATH);
btn.setOnClickListener(this);
if (Build.VERSION.SDK_INT >= 23) {
if (checkSelfPermission(Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED ||
checkSelfPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
requestPermissions(new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE, Manifest.permission.READ_EXTERNAL_STORAGE}, PERMISSION_REQUEST_CODE);
}
}
//Android6.0之前安装时就能复制，6.0之后要先请求权限，所以6.0以上的这个方法无用。
copyToSD(LANGUAGE_PATH, DEFAULT_LANGUAGE_NAME);
btn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
new Thread(new Runnable() {
@Override
public void run() {
Log.i(TAG, "run: kaishi " + System.currentTimeMillis());
Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.yinni);
Log.i(TAG, "run: bitmap " + System.currentTimeMillis());
TessBaseAPI tessBaseAPI = new TessBaseAPI();
tessBaseAPI.init(DATAPATH, DEFAULT_LANGUAGE);
tessBaseAPI.setImage(bitmap);
final String text = tessBaseAPI.getUTF8Text();
Log.i(TAG, "run: text " + System.currentTimeMillis() + text);
runOnUiThread(new Runnable() {
@Override
public void run() {
tv.setText(text);
Log.d("dddd","识别结果"+text);
}
});
tessBaseAPI.end();
}
}).start();
}
});
}
@Override
protected void onResume() {
super.onResume();
runOnUiThread(new Runnable() {
@Override
public void run() {
cropView.setImageDrawable(getResources().getDrawable(R.drawable.yinni));
}
});
}
/**
* 将assets中的识别库复制到SD卡中
* @param path 要存放在SD卡中的 完整的文件名。这里是"/storage/emulated/0//tessdata/chi_sim.traineddata"
* @param name assets中的文件名 这里是 "chi_sim.traineddata"
*/
public void copyToSD(String path, String name) {
Log.i(TAG, "copyToSD: "+path);
Log.i(TAG, "copyToSD: "+name);
//如果存在就删掉
File f = new File(path);
if (f.exists()){
f.delete();
}
if (!f.exists()){
File p = new File(f.getParent());
if (!p.exists()){
p.mkdirs();
}
try {
f.createNewFile();
} catch (IOException e) {
e.printStackTrace();
}
}
InputStream is=null;
OutputStream os=null;
try {
is = this.getAssets().open(name);
File file = new File(path);
os = new FileOutputStream(file);
byte[] bytes = new byte[2048];
int len = 0;
while ((len = is.read(bytes)) != -1) {
os.write(bytes, 0, len);
}
os.flush();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (is != null)
is.close();
if (os != null)
os.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
@Override
public void onClick(View v) {
// switch (v.getId()) {
// case R.id.btn:
// break;
// }
}
public boolean checkTraineddataExists(){
File file = new File(LANGUAGE_PATH);
return file.exists();
}
/**
* 请求到权限后在这里复制识别库
* @param requestCode
* @param permissions
* @param grantResults
*/
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
Log.i(TAG, "onRequestPermissionsResult: "+grantResults[0]);
switch (requestCode){
case PERMISSION_REQUEST_CODE:
if (grantResults.length>0&&grantResults[0]==PackageManager.PERMISSION_GRANTED){
Log.i(TAG, "onRequestPermissionsResult: copy");
copyToSD(LANGUAGE_PATH, DEFAULT_LANGUAGE_NAME);
}
break;
default:
break;
}
}
/**
* 识别图像
*
* @param bitmap
*/
private void recognition(final Bitmap bitmap) {
new Thread(new Runnable() {
@Override
public void run() {
String text="";
if (!checkTraineddataExists()){
text+=LANGUAGE_PATH+"不存在，开始复制\r\n";
Log.i(TAG, "run: "+LANGUAGE_PATH+"不存在，开始复制\r\n");
assets2SD(getApplicationContext(), LANGUAGE_PATH, DEFAULT_LANGUAGE_NAME);
}
text+=LANGUAGE_PATH+"已经存在，开始识别\r\n";
Log.i(TAG, "run: "+LANGUAGE_PATH+"已经存在，开始识别\r\n");
long startTime = System.currentTimeMillis();
Log.i(TAG, "run: kaishi " + startTime);
TessBaseAPI tessBaseAPI = new TessBaseAPI();
tessBaseAPI.init(DATAPATH, DEFAULT_LANGUAGE);
tessBaseAPI.setImage(bitmap);
text =text+"识别结果："+ tessBaseAPI.getUTF8Text();
long finishTime = System.currentTimeMillis();
Log.i(TAG, "run: jieshu " + finishTime);
Log.i(TAG, "run: text " + text);
text = text + "\r\n" + " 耗时" + (finishTime - startTime) + "毫秒";
final String finalText = text;
final Bitmap finalBitmap = bitmap;
runOnUiThread(new Runnable() {
@Override
public void run() {
tv.setText(finalText);
cropView.setImageBitmap(finalBitmap);
}
});
tessBaseAPI.end();
}
}).start();
}
}