[Android] Support PP-OCRv2 & PP-OCRv3 in Android (#445)

* [Android] Add Android build docs and demo (#26) * [Backend] Add override flag to lite backend * [Docs] Add Android C++ SDK build docs * [Doc] fix android_build_docs typos * Update CMakeLists.txt * Update android.md * [Doc] Add PicoDet Android demo docs * [Doc] Update PicoDet Andorid demo docs * [Doc] Update PaddleClasModel Android demo docs * [Doc] Update fastdeploy android jni docs * [Doc] Update fastdeploy android jni usage docs * [Android] init fastdeploy android jar package * [Backend] support int8 option for lite backend * [Model] add Backend::Lite to paddle model * [Backend] use CopyFromCpu for lite backend. * [Android] package jni srcs and java api into aar * Update infer.cc * Update infer.cc * [Android] Update package build.gradle * [Android] Update android app examples * [Android] update android detection app * [Android] Support PP-OCRv2 & PP-OCRv3 in Android * [Android] bind ORCResult with JNI * [Android] move static class jni method to instance method * [Android] bind VisOcr and VisClassification via JNI * [Android] Add PP-OCRv2 & v3 android demo
2025-10-05 08:37:06 +08:00 · 2022-10-28 10:56:47 +08:00
parent 3c208125b8
commit 04704c8411
32 changed files with 8706 additions and 78 deletions
--- a/java/android/app/src/main/AndroidManifest.xml
+++ b/java/android/app/src/main/AndroidManifest.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="com.baidu.paddle.fastdeploy.app.examples.detection">
+    package="com.baidu.paddle.fastdeploy.app.examples">

    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
@@ -11,18 +11,18 @@
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
-        android:label="@string/app_name"
+        android:label="@string/ocr_app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
-        <activity android:name="com.baidu.paddle.fastdeploy.app.examples.detection.MainActivity">
+        <activity android:name="com.baidu.paddle.fastdeploy.app.examples.ocr.MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>
        <activity
-            android:name="com.baidu.paddle.fastdeploy.app.examples.detection.SettingsActivity"
+            android:name="com.baidu.paddle.fastdeploy.app.examples.ocr.SettingsActivity"
            android:label="Settings">
        </activity>
    </application>
--- a/java/android/app/src/main/assets/labels/en_dict.txt
+++ b/java/android/app/src/main/assets/labels/en_dict.txt
@@ -0,0 +1,94 @@
+0
+1
+2
+3
+4
+5
+6
+7
+8
+9
+:
+;
+<
+=
+>
+?
+@
+A
+B
+C
+D
+E
+F
+G
+H
+I
+J
+K
+L
+M
+N
+O
+P
+Q
+R
+S
+T
+U
+V
+W
+X
+Y
+Z
+[
+\
+]
+^
+_
+`
+a
+b
+c
+d
+e
+f
+g
+h
+i
+j
+k
+l
+m
+n
+o
+p
+q
+r
+s
+t
+u
+v
+w
+x
+y
+z
+{
+|
+}
+~
+!
+"
+#
+$
+%
+&
+'
+(
+)
+*
+
+,
+-
+.
+/
--- a/java/android/app/src/main/assets/labels/ppocr_keys_v1.txt
+++ b/java/android/app/src/main/assets/labels/ppocr_keys_v1.txt
--- a/java/android/app/src/main/java/com/baidu/paddle/fastdeploy/app/examples/detection/MainActivity.java
+++ b/java/android/app/src/main/java/com/baidu/paddle/fastdeploy/app/examples/detection/MainActivity.java
@@ -24,7 +24,7 @@ import android.widget.TextView;
 import android.widget.Toast;

 import com.baidu.paddle.fastdeploy.RuntimeOption;
-import com.baidu.paddle.fastdeploy.app.examples.detection.R;
+import com.baidu.paddle.fastdeploy.app.examples.R;
 import com.baidu.paddle.fastdeploy.app.ui.CameraSurfaceView;
 import com.baidu.paddle.fastdeploy.app.ui.Utils;
 import com.baidu.paddle.fastdeploy.vision.DetectionResult;
--- a/java/android/app/src/main/java/com/baidu/paddle/fastdeploy/app/examples/detection/SettingsActivity.java
+++ b/java/android/app/src/main/java/com/baidu/paddle/fastdeploy/app/examples/detection/SettingsActivity.java
@@ -9,7 +9,7 @@ import android.preference.ListPreference;
 import android.preference.PreferenceManager;
 import android.support.v7.app.ActionBar;

-import com.baidu.paddle.fastdeploy.app.examples.detection.R;
+import com.baidu.paddle.fastdeploy.app.examples.R;
 import com.baidu.paddle.fastdeploy.app.ui.AppCompatPreferenceActivity;
 import com.baidu.paddle.fastdeploy.app.ui.Utils;

@@ -46,7 +46,8 @@ public class SettingsActivity extends AppCompatPreferenceActivity implements
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
-        addPreferencesFromResource(R.xml.settings);
+        // addPreferencesFromResource(R.xml.settings);
+        addPreferencesFromResource(R.xml.detection_settings);
        ActionBar supportActionBar = getSupportActionBar();
        if (supportActionBar != null) {
            supportActionBar.setDisplayHomeAsUpEnabled(true);
--- a/java/android/app/src/main/java/com/baidu/paddle/fastdeploy/app/examples/ocr/MainActivity.java
+++ b/java/android/app/src/main/java/com/baidu/paddle/fastdeploy/app/examples/ocr/MainActivity.java
@@ -0,0 +1,289 @@
+package com.baidu.paddle.fastdeploy.app.examples.ocr;
+
+
+import android.Manifest;
+import android.annotation.SuppressLint;
+import android.app.Activity;
+import android.app.AlertDialog;
+import android.content.DialogInterface;
+import android.content.Intent;
+import android.content.SharedPreferences;
+import android.content.pm.PackageManager;
+import android.graphics.Bitmap;
+import android.os.Bundle;
+import android.preference.PreferenceManager;
+import android.support.annotation.NonNull;
+import android.support.v4.app.ActivityCompat;
+import android.support.v4.content.ContextCompat;
+import android.view.View;
+import android.view.Window;
+import android.view.WindowManager;
+import android.widget.ImageButton;
+import android.widget.ImageView;
+import android.widget.TextView;
+import android.widget.Toast;
+
+import com.baidu.paddle.fastdeploy.RuntimeOption;
+import com.baidu.paddle.fastdeploy.app.examples.R;
+import com.baidu.paddle.fastdeploy.app.ui.CameraSurfaceView;
+import com.baidu.paddle.fastdeploy.app.ui.Utils;
+import com.baidu.paddle.fastdeploy.vision.OCRResult;
+import com.baidu.paddle.fastdeploy.pipeline.PPOCRv2;
+import com.baidu.paddle.fastdeploy.vision.ocr.Classifier;
+import com.baidu.paddle.fastdeploy.vision.ocr.DBDetector;
+import com.baidu.paddle.fastdeploy.vision.ocr.Recognizer;
+
+import java.io.File;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+
+public class MainActivity extends Activity implements View.OnClickListener, CameraSurfaceView.OnTextureChangedListener {
+    private static final String TAG = MainActivity.class.getSimpleName();
+
+    CameraSurfaceView svPreview;
+    TextView tvStatus;
+    ImageButton btnSwitch;
+    ImageButton btnShutter;
+    ImageButton btnSettings;
+    ImageView realtimeToggleButton;
+    boolean isRealtimeStatusRunning = false;
+    ImageView backInPreview;
+
+    String savedImagePath = "result.jpg";
+    int lastFrameIndex = 0;
+    long lastFrameTime;
+
+    // Call 'init' and 'release' manually later
+    PPOCRv2 predictor = new PPOCRv2();
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+
+        // Fullscreen
+        requestWindowFeature(Window.FEATURE_NO_TITLE);
+        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
+
+        setContentView(R.layout.activity_main);
+
+        // Clear all setting items to avoid app crashing due to the incorrect settings
+        initSettings();
+
+        // Init the camera preview and UI components
+        initView();
+
+        // Check and request CAMERA and WRITE_EXTERNAL_STORAGE permissions
+        if (!checkAllPermissions()) {
+            requestAllPermissions();
+        }
+    }
+
+    @SuppressLint("NonConstantResourceId")
+    @Override
+    public void onClick(View v) {
+        switch (v.getId()) {
+            case R.id.btn_switch:
+                svPreview.switchCamera();
+                break;
+            case R.id.btn_shutter:
+                @SuppressLint("SimpleDateFormat")
+                SimpleDateFormat date = new SimpleDateFormat("yyyy_MM_dd_HH_mm_ss");
+                synchronized (this) {
+                    savedImagePath = Utils.getDCIMDirectory() + File.separator + date.format(new Date()).toString() + ".png";
+                }
+                Toast.makeText(MainActivity.this, "Save snapshot to " + savedImagePath, Toast.LENGTH_SHORT).show();
+                break;
+            case R.id.btn_settings:
+                startActivity(new Intent(MainActivity.this, SettingsActivity.class));
+                break;
+            case R.id.realtime_toggle_btn:
+                toggleRealtimeStyle();
+                break;
+            case R.id.back_in_preview:
+                finish();
+                break;
+        }
+    }
+
+    private void toggleRealtimeStyle() {
+        if (isRealtimeStatusRunning) {
+            isRealtimeStatusRunning = false;
+            realtimeToggleButton.setImageResource(R.drawable.realtime_stop_btn);
+            svPreview.setOnTextureChangedListener(this);
+            tvStatus.setVisibility(View.VISIBLE);
+        } else {
+            isRealtimeStatusRunning = true;
+            realtimeToggleButton.setImageResource(R.drawable.realtime_start_btn);
+            tvStatus.setVisibility(View.GONE);
+            svPreview.setOnTextureChangedListener(new CameraSurfaceView.OnTextureChangedListener() {
+                @Override
+                public boolean onTextureChanged(Bitmap ARGB8888ImageBitmap) {
+                    return false;
+                }
+            });
+        }
+    }
+
+    @Override
+    public boolean onTextureChanged(Bitmap ARGB8888ImageBitmap) {
+        String savedImagePath = "";
+        synchronized (this) {
+            savedImagePath = MainActivity.this.savedImagePath;
+        }
+        boolean modified = false;
+        OCRResult result = predictor.predict(ARGB8888ImageBitmap, savedImagePath);
+        modified = result.initialized();
+        if (!savedImagePath.isEmpty()) {
+            synchronized (this) {
+                MainActivity.this.savedImagePath = "result.jpg";
+            }
+        }
+        lastFrameIndex++;
+        if (lastFrameIndex >= 30) {
+            final int fps = (int) (lastFrameIndex * 1e9 / (System.nanoTime() - lastFrameTime));
+            runOnUiThread(new Runnable() {
+                @SuppressLint("SetTextI18n")
+                public void run() {
+                    tvStatus.setText(Integer.toString(fps) + "fps");
+                }
+            });
+            lastFrameIndex = 0;
+            lastFrameTime = System.nanoTime();
+        }
+        return modified;
+    }
+
+    @Override
+    protected void onResume() {
+        super.onResume();
+        // Reload settings and re-initialize the predictor
+        checkAndUpdateSettings();
+        // Open camera until the permissions have been granted
+        if (!checkAllPermissions()) {
+            svPreview.disableCamera();
+        }
+        svPreview.onResume();
+    }
+
+    @Override
+    protected void onPause() {
+        super.onPause();
+        svPreview.onPause();
+    }
+
+    @Override
+    protected void onDestroy() {
+        if (predictor != null) {
+            predictor.release();
+        }
+        super.onDestroy();
+    }
+
+    public void initView() {
+        svPreview = (CameraSurfaceView) findViewById(R.id.sv_preview);
+        svPreview.setOnTextureChangedListener(this);
+        tvStatus = (TextView) findViewById(R.id.tv_status);
+        btnSwitch = (ImageButton) findViewById(R.id.btn_switch);
+        btnSwitch.setOnClickListener(this);
+        btnShutter = (ImageButton) findViewById(R.id.btn_shutter);
+        btnShutter.setOnClickListener(this);
+        btnSettings = (ImageButton) findViewById(R.id.btn_settings);
+        btnSettings.setOnClickListener(this);
+        realtimeToggleButton = findViewById(R.id.realtime_toggle_btn);
+        realtimeToggleButton.setOnClickListener(this);
+        backInPreview = findViewById(R.id.back_in_preview);
+        backInPreview.setOnClickListener(this);
+    }
+
+    @SuppressLint("ApplySharedPref")
+    public void initSettings() {
+        SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
+        SharedPreferences.Editor editor = sharedPreferences.edit();
+        editor.clear();
+        editor.commit();
+        SettingsActivity.resetSettings();
+    }
+
+    public void checkAndUpdateSettings() {
+        if (SettingsActivity.checkAndUpdateSettings(this)) {
+            String realModelDir = getCacheDir() + "/" + SettingsActivity.modelDir;
+            // String detModelName = "ch_PP-OCRv2_det_infer";
+            String detModelName = "ch_PP-OCRv3_det_infer";
+            // String detModelName = "ch_ppocr_mobile_v2.0_det_infer";
+            String clsModelName = "ch_ppocr_mobile_v2.0_cls_infer";
+            // String recModelName = "ch_ppocr_mobile_v2.0_rec_infer";
+            String recModelName = "ch_PP-OCRv3_rec_infer";
+            // String recModelName = "ch_PP-OCRv2_rec_infer";
+            String realDetModelDir = realModelDir + "/" + detModelName;
+            String realClsModelDir = realModelDir + "/" + clsModelName;
+            String realRecModelDir = realModelDir + "/" + recModelName;
+            String srcDetModelDir =  SettingsActivity.modelDir + "/" + detModelName;
+            String srcClsModelDir =  SettingsActivity.modelDir + "/" + clsModelName;
+            String srcRecModelDir =  SettingsActivity.modelDir + "/" + recModelName;
+            Utils.copyDirectoryFromAssets(this, srcDetModelDir, realDetModelDir);
+            Utils.copyDirectoryFromAssets(this, srcClsModelDir, realClsModelDir);
+            Utils.copyDirectoryFromAssets(this, srcRecModelDir, realRecModelDir);
+            String realLabelPath = getCacheDir() + "/" + SettingsActivity.labelPath;
+            Utils.copyFileFromAssets(this, SettingsActivity.labelPath, realLabelPath);
+
+            String detModelFile = realDetModelDir + "/" + "inference.pdmodel";
+            String detParamsFile = realDetModelDir + "/" + "inference.pdiparams";
+            String clsModelFile = realClsModelDir + "/" + "inference.pdmodel";
+            String clsParamsFile = realClsModelDir + "/" + "inference.pdiparams";
+            String recModelFile = realRecModelDir + "/" + "inference.pdmodel";
+            String recParamsFile = realRecModelDir + "/" + "inference.pdiparams";
+            String recLabelFilePath = realLabelPath; // ppocr_keys_v1.txt
+            RuntimeOption detOption = new RuntimeOption();
+            RuntimeOption clsOption = new RuntimeOption();
+            RuntimeOption recOption = new RuntimeOption();
+            detOption.setCpuThreadNum(SettingsActivity.cpuThreadNum);
+            clsOption.setCpuThreadNum(SettingsActivity.cpuThreadNum);
+            recOption.setCpuThreadNum(SettingsActivity.cpuThreadNum);
+            detOption.setLitePowerMode(SettingsActivity.cpuPowerMode);
+            clsOption.setLitePowerMode(SettingsActivity.cpuPowerMode);
+            recOption.setLitePowerMode(SettingsActivity.cpuPowerMode);
+            detOption.enableRecordTimeOfRuntime();
+            clsOption.enableRecordTimeOfRuntime();
+            recOption.enableRecordTimeOfRuntime();
+            if (Boolean.parseBoolean(SettingsActivity.enableLiteFp16)) {
+                detOption.enableLiteFp16();
+                clsOption.enableLiteFp16();
+                recOption.enableLiteFp16();
+            }
+            DBDetector detModel = new DBDetector(detModelFile, detParamsFile, detOption);
+            Classifier clsModel = new Classifier(clsModelFile, clsParamsFile, clsOption);
+            Recognizer recModel = new Recognizer(recModelFile, recParamsFile, recLabelFilePath, recOption);
+            predictor.init(detModel, clsModel, recModel);
+
+        }
+    }
+
+    @Override
+    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions,
+                                           @NonNull int[] grantResults) {
+        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
+        if (grantResults[0] != PackageManager.PERMISSION_GRANTED || grantResults[1] != PackageManager.PERMISSION_GRANTED) {
+            new AlertDialog.Builder(MainActivity.this)
+                    .setTitle("Permission denied")
+                    .setMessage("Click to force quit the app, then open Settings->Apps & notifications->Target " +
+                            "App->Permissions to grant all of the permissions.")
+                    .setCancelable(false)
+                    .setPositiveButton("Exit", new DialogInterface.OnClickListener() {
+                        @Override
+                        public void onClick(DialogInterface dialog, int which) {
+                            MainActivity.this.finish();
+                        }
+                    }).show();
+        }
+    }
+
+    private void requestAllPermissions() {
+        ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE,
+                Manifest.permission.CAMERA}, 0);
+    }
+
+    private boolean checkAllPermissions() {
+        return ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED
+                && ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED;
+    }
+}
--- a/java/android/app/src/main/java/com/baidu/paddle/fastdeploy/app/examples/ocr/SettingsActivity.java
+++ b/java/android/app/src/main/java/com/baidu/paddle/fastdeploy/app/examples/ocr/SettingsActivity.java
@@ -0,0 +1,198 @@
+package com.baidu.paddle.fastdeploy.app.examples.ocr;
+
+import android.annotation.SuppressLint;
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.os.Bundle;
+import android.preference.EditTextPreference;
+import android.preference.ListPreference;
+import android.preference.PreferenceManager;
+import android.support.v7.app.ActionBar;
+
+import com.baidu.paddle.fastdeploy.app.examples.R;
+import com.baidu.paddle.fastdeploy.app.ui.AppCompatPreferenceActivity;
+import com.baidu.paddle.fastdeploy.app.ui.Utils;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class SettingsActivity extends AppCompatPreferenceActivity implements
+        SharedPreferences.OnSharedPreferenceChangeListener {
+    private static final String TAG = SettingsActivity.class.getSimpleName();
+
+    static public int selectedModelIdx = -1;
+    static public String modelDir = "";
+    static public String labelPath = "";
+    static public int cpuThreadNum = 2;
+    static public String cpuPowerMode = "";
+    static public float scoreThreshold = 0.4f;
+    static public String enableLiteFp16 = "true";
+
+    ListPreference lpChoosePreInstalledModel = null;
+    EditTextPreference etModelDir = null;
+    EditTextPreference etLabelPath = null;
+    ListPreference lpCPUThreadNum = null;
+    ListPreference lpCPUPowerMode = null;
+    EditTextPreference etScoreThreshold = null;
+    ListPreference lpEnableLiteFp16 = null;
+
+    List<String> preInstalledModelDirs = null;
+    List<String> preInstalledLabelPaths = null;
+    List<String> preInstalledCPUThreadNums = null;
+    List<String> preInstalledCPUPowerModes = null;
+    List<String> preInstalledScoreThresholds = null;
+    List<String> preInstalledEnableLiteFp16s = null;
+
+    @Override
+    public void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        addPreferencesFromResource(R.xml.ocr_settings);
+        ActionBar supportActionBar = getSupportActionBar();
+        if (supportActionBar != null) {
+            supportActionBar.setDisplayHomeAsUpEnabled(true);
+        }
+
+        // Initialize pre-installed models
+        preInstalledModelDirs = new ArrayList<String>();
+        preInstalledLabelPaths = new ArrayList<String>();
+        preInstalledCPUThreadNums = new ArrayList<String>();
+        preInstalledCPUPowerModes = new ArrayList<String>();
+        preInstalledScoreThresholds = new ArrayList<String>();
+        preInstalledEnableLiteFp16s = new ArrayList<String>();
+        preInstalledModelDirs.add(getString(R.string.OCR_MODEL_DIR_DEFAULT));
+        preInstalledLabelPaths.add(getString(R.string.OCR_REC_LABEL_DEFAULT));
+        preInstalledCPUThreadNums.add(getString(R.string.CPU_THREAD_NUM_DEFAULT));
+        preInstalledCPUPowerModes.add(getString(R.string.CPU_POWER_MODE_DEFAULT));
+        preInstalledScoreThresholds.add(getString(R.string.SCORE_THRESHOLD_DEFAULT));
+        preInstalledEnableLiteFp16s.add(getString(R.string.ENABLE_LITE_FP16_MODE_DEFAULT));
+
+        // Setup UI components
+        lpChoosePreInstalledModel =
+                (ListPreference) findPreference(getString(R.string.CHOOSE_PRE_INSTALLED_MODEL_KEY));
+        String[] preInstalledModelNames = new String[preInstalledModelDirs.size()];
+        for (int i = 0; i < preInstalledModelDirs.size(); i++) {
+            preInstalledModelNames[i] = preInstalledModelDirs.get(i).substring(preInstalledModelDirs.get(i).lastIndexOf("/") + 1);
+        }
+        lpChoosePreInstalledModel.setEntries(preInstalledModelNames);
+        lpChoosePreInstalledModel.setEntryValues(preInstalledModelDirs.toArray(new String[preInstalledModelDirs.size()]));
+        lpCPUThreadNum = (ListPreference) findPreference(getString(R.string.CPU_THREAD_NUM_KEY));
+        lpCPUPowerMode = (ListPreference) findPreference(getString(R.string.CPU_POWER_MODE_KEY));
+        etModelDir = (EditTextPreference) findPreference(getString(R.string.MODEL_DIR_KEY));
+        etModelDir.setTitle("Model dir (SDCard: " + Utils.getSDCardDirectory() + ")");
+        etLabelPath = (EditTextPreference) findPreference(getString(R.string.LABEL_PATH_KEY));
+        etLabelPath.setTitle("Label path (SDCard: " + Utils.getSDCardDirectory() + ")");
+        etScoreThreshold = (EditTextPreference) findPreference(getString(R.string.SCORE_THRESHOLD_KEY));
+        lpEnableLiteFp16 = (ListPreference) findPreference(getString(R.string.ENABLE_LITE_FP16_MODE_KEY));
+    }
+
+    @SuppressLint("ApplySharedPref")
+    private void reloadSettingsAndUpdateUI() {
+        SharedPreferences sharedPreferences = getPreferenceScreen().getSharedPreferences();
+
+        String selected_model_dir = sharedPreferences.getString(getString(R.string.CHOOSE_PRE_INSTALLED_MODEL_KEY),
+                getString(R.string.OCR_MODEL_DIR_DEFAULT));
+        int selected_model_idx = lpChoosePreInstalledModel.findIndexOfValue(selected_model_dir);
+        if (selected_model_idx >= 0 && selected_model_idx < preInstalledModelDirs.size() && selected_model_idx != selectedModelIdx) {
+            SharedPreferences.Editor editor = sharedPreferences.edit();
+            editor.putString(getString(R.string.MODEL_DIR_KEY), preInstalledModelDirs.get(selected_model_idx));
+            editor.putString(getString(R.string.LABEL_PATH_KEY), preInstalledLabelPaths.get(selected_model_idx));
+            editor.putString(getString(R.string.CPU_THREAD_NUM_KEY), preInstalledCPUThreadNums.get(selected_model_idx));
+            editor.putString(getString(R.string.CPU_POWER_MODE_KEY), preInstalledCPUPowerModes.get(selected_model_idx));
+            editor.putString(getString(R.string.SCORE_THRESHOLD_KEY), preInstalledScoreThresholds.get(selected_model_idx));
+            editor.putString(getString(R.string.ENABLE_LITE_FP16_MODE_DEFAULT), preInstalledEnableLiteFp16s.get(selected_model_idx));
+            editor.commit();
+            lpChoosePreInstalledModel.setSummary(selected_model_dir);
+            selectedModelIdx = selected_model_idx;
+        }
+
+        String model_dir = sharedPreferences.getString(getString(R.string.MODEL_DIR_KEY),
+                getString(R.string.OCR_MODEL_DIR_DEFAULT));
+        String label_path = sharedPreferences.getString(getString(R.string.LABEL_PATH_KEY),
+                getString(R.string.OCR_REC_LABEL_DEFAULT));
+        String cpu_thread_num = sharedPreferences.getString(getString(R.string.CPU_THREAD_NUM_KEY),
+                getString(R.string.CPU_THREAD_NUM_DEFAULT));
+        String cpu_power_mode = sharedPreferences.getString(getString(R.string.CPU_POWER_MODE_KEY),
+                getString(R.string.CPU_POWER_MODE_DEFAULT));
+        String score_threshold = sharedPreferences.getString(getString(R.string.SCORE_THRESHOLD_KEY),
+                getString(R.string.SCORE_THRESHOLD_DEFAULT));
+        String enable_lite_fp16 = sharedPreferences.getString(getString(R.string.ENABLE_LITE_FP16_MODE_KEY),
+                getString(R.string.ENABLE_LITE_FP16_MODE_DEFAULT));
+
+        etModelDir.setSummary(model_dir);
+        etLabelPath.setSummary(label_path);
+        lpCPUThreadNum.setValue(cpu_thread_num);
+        lpCPUThreadNum.setSummary(cpu_thread_num);
+        lpCPUPowerMode.setValue(cpu_power_mode);
+        lpCPUPowerMode.setSummary(cpu_power_mode);
+        etScoreThreshold.setSummary(score_threshold);
+        etScoreThreshold.setText(score_threshold);
+        lpEnableLiteFp16.setValue(enable_lite_fp16);
+        lpEnableLiteFp16.setSummary(enable_lite_fp16);
+
+    }
+
+    static boolean checkAndUpdateSettings(Context ctx) {
+        boolean settingsChanged = false;
+        SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(ctx);
+
+        String model_dir = sharedPreferences.getString(ctx.getString(R.string.MODEL_DIR_KEY),
+                ctx.getString(R.string.OCR_MODEL_DIR_DEFAULT));
+        settingsChanged |= !modelDir.equalsIgnoreCase(model_dir);
+        modelDir = model_dir;
+
+        String label_path = sharedPreferences.getString(ctx.getString(R.string.LABEL_PATH_KEY),
+                ctx.getString(R.string.OCR_REC_LABEL_DEFAULT));
+        settingsChanged |= !labelPath.equalsIgnoreCase(label_path);
+        labelPath = label_path;
+
+        String cpu_thread_num = sharedPreferences.getString(ctx.getString(R.string.CPU_THREAD_NUM_KEY),
+                ctx.getString(R.string.CPU_THREAD_NUM_DEFAULT));
+        settingsChanged |= cpuThreadNum != Integer.parseInt(cpu_thread_num);
+        cpuThreadNum = Integer.parseInt(cpu_thread_num);
+
+        String cpu_power_mode = sharedPreferences.getString(ctx.getString(R.string.CPU_POWER_MODE_KEY),
+                ctx.getString(R.string.CPU_POWER_MODE_DEFAULT));
+        settingsChanged |= !cpuPowerMode.equalsIgnoreCase(cpu_power_mode);
+        cpuPowerMode = cpu_power_mode;
+
+        String score_threshold = sharedPreferences.getString(ctx.getString(R.string.SCORE_THRESHOLD_KEY),
+                ctx.getString(R.string.SCORE_THRESHOLD_DEFAULT));
+        settingsChanged |= scoreThreshold != Float.parseFloat(score_threshold);
+        scoreThreshold = Float.parseFloat(score_threshold);
+
+        String enable_lite_fp16 = sharedPreferences.getString(ctx.getString(R.string.ENABLE_LITE_FP16_MODE_KEY),
+                ctx.getString(R.string.ENABLE_LITE_FP16_MODE_DEFAULT));
+        settingsChanged |= !enableLiteFp16.equalsIgnoreCase(enable_lite_fp16);
+        enableLiteFp16 = enable_lite_fp16;
+
+        return settingsChanged;
+    }
+
+    static void resetSettings() {
+        selectedModelIdx = -1;
+        modelDir = "";
+        labelPath = "";
+        cpuThreadNum = 2;
+        cpuPowerMode = "";
+        scoreThreshold = 0.4f;
+        enableLiteFp16 = "true";
+    }
+
+    @Override
+    protected void onResume() {
+        super.onResume();
+        getPreferenceScreen().getSharedPreferences().registerOnSharedPreferenceChangeListener(this);
+        reloadSettingsAndUpdateUI();
+    }
+
+    @Override
+    protected void onPause() {
+        super.onPause();
+        getPreferenceScreen().getSharedPreferences().unregisterOnSharedPreferenceChangeListener(this);
+    }
+
+    @Override
+    public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
+        reloadSettingsAndUpdateUI();
+    }
+}
--- a/java/android/app/src/main/res/layout-land/activity_main.xml
+++ b/java/android/app/src/main/res/layout-land/activity_main.xml
@@ -5,7 +5,7 @@
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:keepScreenOn="true"
-    tools:context="com.baidu.paddle.fastdeploy.app.examples.detection.MainActivity">
+    tools:context="com.baidu.paddle.fastdeploy.app.examples.ocr.MainActivity">

    <RelativeLayout
        android:layout_width="match_parent"
--- a/java/android/app/src/main/res/layout/activity_main.xml
+++ b/java/android/app/src/main/res/layout/activity_main.xml
@@ -5,7 +5,7 @@
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:keepScreenOn="true"
-    tools:context="com.baidu.paddle.fastdeploy.app.examples.detection.MainActivity">
+    tools:context="com.baidu.paddle.fastdeploy.app.examples.ocr.MainActivity">

    <RelativeLayout
        android:layout_width="match_parent"
--- a/java/android/app/src/main/res/values/strings.xml
+++ b/java/android/app/src/main/res/values/strings.xml
@@ -1,5 +1,10 @@
 <resources>
+    <!-- Default App name -->
    <string name="app_name">FastDeploy PicoDet</string>
+    <!-- Other App name -->
+    <string name="detection_app_name">FastDeploy PicoDet</string>
+    <string name="ocr_app_name">FastDeploy PP-OCRv2</string>
+    <!-- Keys for PreferenceScreen -->
    <string name="CHOOSE_PRE_INSTALLED_MODEL_KEY">CHOOSE_INSTALLED_MODEL_KEY</string>
    <string name="MODEL_DIR_KEY">MODEL_DIR_KEY</string>
    <string name="LABEL_PATH_KEY">LABEL_PATH_KEY</string>
@@ -7,13 +12,18 @@
    <string name="CPU_POWER_MODE_KEY">CPU_POWER_MODE_KEY</string>
    <string name="SCORE_THRESHOLD_KEY">SCORE_THRESHOLD_KEY</string>
    <string name="ENABLE_LITE_FP16_MODE_KEY">ENABLE_LITE_FP16_MODE_KEY</string>
-    <string name="MODEL_DIR_DEFAULT">models/picodet_s_320_coco_lcnet</string>
-    <string name="LABEL_PATH_DEFAULT">labels/coco_label_list.txt</string>
+    <!-- Common default values ... -->
    <string name="CPU_THREAD_NUM_DEFAULT">2</string>
    <string name="CPU_POWER_MODE_DEFAULT">LITE_POWER_HIGH</string>
    <string name="SCORE_THRESHOLD_DEFAULT">0.4</string>
    <string name="ENABLE_LITE_FP16_MODE_DEFAULT">true</string>
-    <!--Other values-->
+    <!-- Default model & Label paths & other values ... -->
+    <string name="MODEL_DIR_DEFAULT">models/picodet_s_320_coco_lcnet</string>
+    <string name="LABEL_PATH_DEFAULT">labels/coco_label_list.txt</string>
+    <!-- PP-OCRv2 & PP-OCRv3 values ... -->
+    <string name="OCR_MODEL_DIR_DEFAULT">models</string>
+    <string name="OCR_REC_LABEL_DEFAULT">labels/ppocr_keys_v1.txt</string>
+    <!-- Other resources values-->
    <string name="action_bar_take_photo">拍照识别</string>
    <string name="action_bar_realtime">FD 实时识别</string>
    <string name="action_bar_back">&lt;</string>
--- a/java/android/app/src/main/res/xml/classification_settings.xml
+++ b/java/android/app/src/main/res/xml/classification_settings.xml
@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
+
+</PreferenceScreen>
--- a/java/android/app/src/main/res/xml/detection_settings.xml
+++ b/java/android/app/src/main/res/xml/detection_settings.xml
@@ -0,0 +1,45 @@
+<?xml version="1.0" encoding="utf-8"?>
+<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
+    <ListPreference
+        android:defaultValue="@string/MODEL_DIR_DEFAULT"
+        android:key="@string/CHOOSE_PRE_INSTALLED_MODEL_KEY"
+        android:negativeButtonText="@null"
+        android:positiveButtonText="@null"
+        android:title="Choose Pre-Installed Models" />
+    <EditTextPreference
+        android:defaultValue="@string/MODEL_DIR_DEFAULT"
+        android:key="@string/MODEL_DIR_KEY"
+        android:title="Model Dir" />
+    <EditTextPreference
+        android:defaultValue="@string/LABEL_PATH_DEFAULT"
+        android:key="@string/LABEL_PATH_KEY"
+        android:title="Label Path" />
+    <ListPreference
+        android:defaultValue="@string/CPU_THREAD_NUM_DEFAULT"
+        android:entries="@array/cpu_thread_num_entries"
+        android:entryValues="@array/cpu_thread_num_values"
+        android:key="@string/CPU_THREAD_NUM_KEY"
+        android:negativeButtonText="@null"
+        android:positiveButtonText="@null"
+        android:title="CPU Thread Num" />
+    <ListPreference
+        android:defaultValue="@string/CPU_POWER_MODE_DEFAULT"
+        android:entries="@array/cpu_power_mode_entries"
+        android:entryValues="@array/cpu_power_mode_values"
+        android:key="@string/CPU_POWER_MODE_KEY"
+        android:negativeButtonText="@null"
+        android:positiveButtonText="@null"
+        android:title="CPU Power Mode" />
+    <EditTextPreference
+        android:key="@string/SCORE_THRESHOLD_KEY"
+        android:defaultValue="@string/SCORE_THRESHOLD_DEFAULT"
+        android:title="Score Threshold: (0.0, 1.0)" />
+    <ListPreference
+        android:defaultValue="@string/ENABLE_LITE_FP16_MODE_DEFAULT"
+        android:entries="@array/enable_lite_fp16_mode_entries"
+        android:entryValues="@array/enable_lite_fp16_mode_values"
+        android:key="@string/ENABLE_LITE_FP16_MODE_KEY"
+        android:negativeButtonText="@null"
+        android:positiveButtonText="@null"
+        android:title="Enable Lite FP16" />
+</PreferenceScreen>
--- a/java/android/app/src/main/res/xml/ocr_settings.xml
+++ b/java/android/app/src/main/res/xml/ocr_settings.xml
@@ -0,0 +1,45 @@
+<?xml version="1.0" encoding="utf-8"?>
+<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
+    <ListPreference
+        android:defaultValue="@string/MODEL_DIR_DEFAULT"
+        android:key="@string/CHOOSE_PRE_INSTALLED_MODEL_KEY"
+        android:negativeButtonText="@null"
+        android:positiveButtonText="@null"
+        android:title="Choose Pre-Installed Models" />
+    <EditTextPreference
+        android:defaultValue="@string/OCR_MODEL_DIR_DEFAULT"
+        android:key="@string/MODEL_DIR_KEY"
+        android:title="Model Dir" />
+    <EditTextPreference
+        android:defaultValue="@string/OCR_REC_LABEL_DEFAULT"
+        android:key="@string/LABEL_PATH_KEY"
+        android:title="Label Path" />
+    <ListPreference
+        android:defaultValue="@string/CPU_THREAD_NUM_DEFAULT"
+        android:entries="@array/cpu_thread_num_entries"
+        android:entryValues="@array/cpu_thread_num_values"
+        android:key="@string/CPU_THREAD_NUM_KEY"
+        android:negativeButtonText="@null"
+        android:positiveButtonText="@null"
+        android:title="CPU Thread Num" />
+    <ListPreference
+        android:defaultValue="@string/CPU_POWER_MODE_DEFAULT"
+        android:entries="@array/cpu_power_mode_entries"
+        android:entryValues="@array/cpu_power_mode_values"
+        android:key="@string/CPU_POWER_MODE_KEY"
+        android:negativeButtonText="@null"
+        android:positiveButtonText="@null"
+        android:title="CPU Power Mode" />
+    <EditTextPreference
+        android:key="@string/SCORE_THRESHOLD_KEY"
+        android:defaultValue="@string/SCORE_THRESHOLD_DEFAULT"
+        android:title="Score Threshold: (0.0, 1.0)" />
+    <ListPreference
+        android:defaultValue="@string/ENABLE_LITE_FP16_MODE_DEFAULT"
+        android:entries="@array/enable_lite_fp16_mode_entries"
+        android:entryValues="@array/enable_lite_fp16_mode_values"
+        android:key="@string/ENABLE_LITE_FP16_MODE_KEY"
+        android:negativeButtonText="@null"
+        android:positiveButtonText="@null"
+        android:title="Enable Lite FP16" />
+</PreferenceScreen>
--- a/java/android/fastdeploy/src/main/cpp/CMakeLists.txt
+++ b/java/android/fastdeploy/src/main/cpp/CMakeLists.txt
@@ -28,6 +28,7 @@ add_library(
        SHARED
        utils_jni.cc
        bitmap_jni.cc
+        pipeline/ppocr_jni.cc
        vision/results_jni.cc
        vision/visualize_jni.cc
        vision/detection/picodet_jni.cc
--- a/java/android/fastdeploy/src/main/cpp/pipeline/ppocr_jni.cc
+++ b/java/android/fastdeploy/src/main/cpp/pipeline/ppocr_jni.cc
@@ -0,0 +1,418 @@
+// Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <jni.h>  // NOLINT
+
+#include "fastdeploy_jni.h"  // NOLINT
+
+namespace fastdeploy {
+namespace jni {
+namespace pipeline {
+
+enum PPOCRVersion {
+  OCR_V1 = 0,
+  OCR_V2 = 1,
+  OCR_V3 = 2
+};
+
+/// Handle the native PP-OCR pipeline resources.
+class PPOCRHandler {
+public:
+  PPOCRHandler() = default;
+
+  PPOCRHandler(fastdeploy::vision::ocr::DBDetector *det_model,
+               fastdeploy::vision::ocr::Classifier *cls_model,
+               fastdeploy::vision::ocr::Recognizer *rec_model,
+               fastdeploy::pipeline::PPOCRv2 *ppocr_v2) :
+      detector_(det_model), classifier_(cls_model),
+      recognizer_(rec_model), ppocr_v2_(ppocr_v2) {
+    if (detector_ != nullptr && classifier_ != nullptr
+        && recognizer_ != nullptr && ppocr_v2_ != nullptr) {
+      initialized_ = true;
+    }
+  }
+
+  PPOCRHandler(fastdeploy::vision::ocr::DBDetector *det_model,
+               fastdeploy::vision::ocr::Recognizer *rec_model,
+               fastdeploy::pipeline::PPOCRv2 *ppocr_v2) :
+      detector_(det_model), recognizer_(rec_model),
+      ppocr_v2_(ppocr_v2) {
+    if (detector_ != nullptr && recognizer_ != nullptr
+        && ppocr_v2_ != nullptr) {
+      initialized_ = true;
+    }
+  }
+
+  PPOCRHandler(fastdeploy::vision::ocr::DBDetector *det_model,
+               fastdeploy::vision::ocr::Classifier *cls_model,
+               fastdeploy::vision::ocr::Recognizer *rec_model,
+               fastdeploy::pipeline::PPOCRv3 *ppocr_v3) :
+      detector_(det_model), classifier_(cls_model),
+      recognizer_(rec_model), ppocr_v3_(ppocr_v3) {
+    if (detector_ != nullptr && classifier_ != nullptr
+        && recognizer_ != nullptr && ppocr_v3_ != nullptr) {
+      initialized_ = true;
+    }
+  }
+
+  PPOCRHandler(fastdeploy::vision::ocr::DBDetector *det_model,
+               fastdeploy::vision::ocr::Recognizer *rec_model,
+               fastdeploy::pipeline::PPOCRv3 *ppocr_v3) :
+      detector_(det_model), recognizer_(rec_model),
+      ppocr_v3_(ppocr_v3) {
+    if (detector_ != nullptr && recognizer_ != nullptr
+        && ppocr_v3_ != nullptr) {
+      initialized_ = true;
+    }
+  }
+
+  void SetPPOCRVersion(PPOCRVersion version_tag) {
+    ppocr_version_tag_ = version_tag;
+  }
+
+  bool Predict(cv::Mat* img, fastdeploy::vision::OCRResult* result) {
+    if (ppocr_version_tag_ == PPOCRVersion::OCR_V2) {
+      if (ppocr_v2_ != nullptr) {
+        return ppocr_v2_->Predict(img, result);
+      }
+      return false;
+    } else if (ppocr_version_tag_ == PPOCRVersion::OCR_V3) {
+      if (ppocr_v3_ != nullptr) {
+        return ppocr_v3_->Predict(img, result);
+      }
+      return false;
+    }
+    return false;
+  }
+
+  bool Initialized() {
+    if (!initialized_) {
+      return false;
+    }
+    if (ppocr_version_tag_ == PPOCRVersion::OCR_V2) {
+      if (ppocr_v2_ != nullptr) {
+        return ppocr_v2_->Initialized();
+      }
+      return false;
+    } else if (ppocr_version_tag_ == PPOCRVersion::OCR_V3) {
+      if (ppocr_v3_ != nullptr) {
+        return ppocr_v3_->Initialized();
+      }
+      return false;
+    }
+    return false;
+  }
+
+  // Call init manually if you want to release the allocated
+  // PP-OCRv2/v3's memory by 'new' operator via 'delete'.
+  bool ReleaseAllocatedOCRMemories() {
+    if (!Initialized()) {
+      return false;
+    }
+    if (detector_ != nullptr) {
+      delete detector_;
+      detector_ = nullptr;
+      LOGD("[End] Release DBDetector in native !");
+    }
+    if (classifier_ != nullptr) {
+      delete classifier_;
+      classifier_ = nullptr;
+      LOGD("[End] Release Classifier in native !");
+    }
+    if (recognizer_ != nullptr) {
+      delete recognizer_;
+      recognizer_ = nullptr;
+      LOGD("[End] Release Recognizer in native !");
+    }
+    if (ppocr_v2_ != nullptr) {
+      delete ppocr_v2_;
+      ppocr_v2_ = nullptr;
+      LOGD("[End] Release PP-OCRv2 in native !");
+    }
+    if (ppocr_v3_ != nullptr) {
+      delete ppocr_v3_;
+      ppocr_v3_ = nullptr;
+      LOGD("[End] Release PP-OCRv3 in native !");
+    }
+    initialized_ = false;
+    return true;
+  }
+
+  void PrintPPOCRHandlerTimeOfRuntime() const {
+    if ((detector_ != nullptr) && (detector_->EnabledRecordTimeOfRuntime())) {
+      auto det_info_of_runtime = detector_->PrintStatisInfoOfRuntime();
+      LOGD("[Det] Avg runtime costs %f ms", det_info_of_runtime["avg_time"] * 1000.0f);
+    }
+    if ((classifier_ != nullptr) && (classifier_->EnabledRecordTimeOfRuntime())) {
+      auto cls_info_of_runtime = classifier_->PrintStatisInfoOfRuntime();
+      LOGD("[Cls] Avg runtime costs %f ms", cls_info_of_runtime["avg_time"] * 1000.0f);
+    }
+    if ((recognizer_ != nullptr) && (recognizer_->EnabledRecordTimeOfRuntime())) {
+      auto rec_info_of_runtime = recognizer_->PrintStatisInfoOfRuntime();
+      LOGD("[Rec] Avg runtime costs %f ms", rec_info_of_runtime["avg_time"] * 1000.0f);
+    }
+  }
+
+public:
+  fastdeploy::vision::ocr::DBDetector *detector_ = nullptr;
+  fastdeploy::vision::ocr::Classifier *classifier_ = nullptr;
+  fastdeploy::vision::ocr::Recognizer *recognizer_ = nullptr;
+  fastdeploy::pipeline::PPOCRv2 *ppocr_v2_ = nullptr;
+  fastdeploy::pipeline::PPOCRv3 *ppocr_v3_ = nullptr;
+
+private:
+  bool initialized_ = false;
+  PPOCRVersion ppocr_version_tag_ = PPOCRVersion::OCR_V2;
+};
+
+}  // namespace pipeline
+}  // namespace jni
+}  // namespace fastdeploy
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+JNIEXPORT jlong JNICALL
+Java_com_baidu_paddle_fastdeploy_pipeline_PPOCRBase_bindNative(
+    JNIEnv *env,
+    jobject thiz,
+    jint ocr_version_tag,
+    jstring det_model_file,
+    jstring det_params_file,
+    jstring cls_model_file,
+    jstring cls_params_file,
+    jstring rec_model_file,
+    jstring rec_params_file,
+    jstring rec_label_path,
+    jint det_cpu_num_thread,
+    jint cls_cpu_num_thread,
+    jint rec_cpu_num_thread,
+    jboolean det_enable_lite_fp16,
+    jboolean cls_enable_lite_fp16,
+    jboolean rec_enable_lite_fp16,
+    jint det_lite_power_mode,
+    jint cls_lite_power_mode,
+    jint rec_lite_power_mode,
+    jstring det_lite_optimized_model_dir,
+    jstring cls_lite_optimized_model_dir,
+    jstring rec_lite_optimized_model_dir,
+    jboolean det_enable_record_time_of_runtime,
+    jboolean cls_enable_record_time_of_runtime,
+    jboolean rec_enable_record_time_of_runtime,
+    jboolean have_cls_model) {
+  auto c_ocr_version_tag = static_cast<
+      fastdeploy::jni::pipeline::PPOCRVersion>(ocr_version_tag);
+  if (c_ocr_version_tag == fastdeploy::jni::pipeline::PPOCRVersion::OCR_V1) {
+    LOGE("Not support for PPOCRVersion::OCR_V1 now!");
+    return 0;
+  }
+  // TODO(qiuyanjun): Allows users to set model parameters, such as det_db_box_thresh,
+  //  det_db_thresh, use_dilation, etc. These parameters should be passed in via JNI.
+  std::string c_det_model_file = fastdeploy::jni::ConvertTo<std::string>(env, det_model_file);
+  std::string c_det_params_file = fastdeploy::jni::ConvertTo<std::string>(env, det_params_file);
+  std::string c_cls_model_file = fastdeploy::jni::ConvertTo<std::string>(env, cls_model_file);
+  std::string c_cls_params_file = fastdeploy::jni::ConvertTo<std::string>(env, cls_params_file);
+  std::string c_rec_model_file = fastdeploy::jni::ConvertTo<std::string>(env, rec_model_file);
+  std::string c_rec_params_file = fastdeploy::jni::ConvertTo<std::string>(env, rec_params_file);
+  std::string c_rec_label_path = fastdeploy::jni::ConvertTo<std::string>(env, rec_label_path);
+  auto c_det_cpu_num_thread = static_cast<int>(det_cpu_num_thread);
+  auto c_cls_cpu_num_thread = static_cast<int>(cls_cpu_num_thread);
+  auto c_rec_cpu_num_thread = static_cast<int>(rec_cpu_num_thread);
+  auto c_det_enable_lite_fp16 = static_cast<bool>(det_enable_lite_fp16);
+  auto c_cls_enable_lite_fp16 = static_cast<bool>(cls_enable_lite_fp16);
+  auto c_rec_enable_lite_fp16 = static_cast<bool>(rec_enable_lite_fp16);
+  auto c_det_lite_power_mode = static_cast<fastdeploy::LitePowerMode>(det_lite_power_mode);
+  auto c_cls_lite_power_mode = static_cast<fastdeploy::LitePowerMode>(cls_lite_power_mode);
+  auto c_rec_lite_power_mode = static_cast<fastdeploy::LitePowerMode>(rec_lite_power_mode);
+  std::string c_det_lite_optimized_model_dir = fastdeploy::jni::ConvertTo<std::string>(
+      env, det_lite_optimized_model_dir);
+  std::string c_cls_lite_optimized_model_dir = fastdeploy::jni::ConvertTo<std::string>(
+      env, cls_lite_optimized_model_dir);
+  std::string c_rec_lite_optimized_model_dir = fastdeploy::jni::ConvertTo<std::string>(
+      env, rec_lite_optimized_model_dir);
+  auto c_det_enable_record_time_of_runtime = static_cast<bool>(det_enable_record_time_of_runtime);
+  auto c_cls_enable_record_time_of_runtime = static_cast<bool>(cls_enable_record_time_of_runtime);
+  auto c_rec_enable_record_time_of_runtime = static_cast<bool>(rec_enable_record_time_of_runtime);
+  auto c_have_cls_model = static_cast<bool>(have_cls_model);
+
+  // RuntimeOptions in native
+  fastdeploy::RuntimeOption c_det_option;
+  c_det_option.UseCpu();
+  c_det_option.UseLiteBackend();
+  c_det_option.SetCpuThreadNum(c_det_cpu_num_thread);
+  c_det_option.SetLitePowerMode(c_det_lite_power_mode);
+  c_det_option.SetLiteOptimizedModelDir(c_det_lite_optimized_model_dir);
+  if (c_det_enable_lite_fp16) {
+    c_det_option.EnableLiteFP16();
+  }
+  fastdeploy::RuntimeOption c_cls_option;
+  c_cls_option.UseCpu();
+  c_cls_option.UseLiteBackend();
+  c_cls_option.SetCpuThreadNum(c_cls_cpu_num_thread);
+  c_cls_option.SetLitePowerMode(c_cls_lite_power_mode);
+  c_cls_option.SetLiteOptimizedModelDir(c_cls_lite_optimized_model_dir);
+  if (c_cls_enable_lite_fp16) {
+    c_cls_option.EnableLiteFP16();
+  }
+  fastdeploy::RuntimeOption c_rec_option;
+  c_rec_option.UseCpu();
+  c_rec_option.UseLiteBackend();
+  c_rec_option.SetCpuThreadNum(c_rec_cpu_num_thread);
+  c_rec_option.SetLitePowerMode(c_rec_lite_power_mode);
+  c_rec_option.SetLiteOptimizedModelDir(c_rec_lite_optimized_model_dir);
+  if (c_rec_enable_lite_fp16) {
+    c_rec_option.EnableLiteFP16();
+  }
+
+  // Init PP-OCR pipeline
+  auto c_det_model_ptr = new fastdeploy::vision::ocr::DBDetector(
+      c_det_model_file, c_det_params_file, c_det_option);
+  auto c_rec_model_ptr = new fastdeploy::vision::ocr::Recognizer(
+      c_rec_model_file, c_rec_params_file, c_rec_label_path, c_rec_option);
+  // Enable record Runtime time costs.
+  if (c_det_enable_record_time_of_runtime) {
+    c_det_model_ptr->EnableRecordTimeOfRuntime();
+  }
+  if (c_rec_enable_record_time_of_runtime) {
+    c_rec_model_ptr->EnableRecordTimeOfRuntime();
+  }
+
+  // PP-OCRv2
+  if (c_ocr_version_tag == fastdeploy::jni::pipeline::PPOCRVersion::OCR_V2) {
+    if (c_have_cls_model) {
+      auto c_cls_model_ptr = new fastdeploy::vision::ocr::Classifier(
+          c_cls_model_file, c_cls_params_file, c_cls_option);
+      if (c_cls_enable_record_time_of_runtime) {
+        c_cls_model_ptr->EnableRecordTimeOfRuntime();
+      }
+      auto c_ppocr_pipeline_ptr = new fastdeploy::pipeline::PPOCRv2(
+          c_det_model_ptr, c_cls_model_ptr, c_rec_model_ptr);
+      // PP-OCRv2 handler with cls model
+      auto c_ppocr_handler_ptr = new fastdeploy::jni::pipeline::PPOCRHandler(
+          c_det_model_ptr, c_cls_model_ptr, c_rec_model_ptr, c_ppocr_pipeline_ptr);
+      c_ppocr_handler_ptr->SetPPOCRVersion(c_ocr_version_tag);
+      // WARN: need to release manually in Java !
+      return reinterpret_cast<jlong>(c_ppocr_handler_ptr);  // native handler context
+    } else {
+      auto c_ppocr_pipeline_ptr = new fastdeploy::pipeline::PPOCRv2(
+          c_det_model_ptr, c_rec_model_ptr);
+      // PP-OCRv2 handler without cls model
+      auto c_ppocr_handler_ptr = new fastdeploy::jni::pipeline::PPOCRHandler(
+          c_det_model_ptr, c_rec_model_ptr, c_ppocr_pipeline_ptr);
+      c_ppocr_handler_ptr->SetPPOCRVersion(c_ocr_version_tag);
+      // WARN: need to release manually in Java !
+      return reinterpret_cast<jlong>(c_ppocr_handler_ptr);  // native handler context
+    }
+  } // PP-OCRv3
+  else if (c_ocr_version_tag == fastdeploy::jni::pipeline::PPOCRVersion::OCR_V3) {
+    if (c_have_cls_model) {
+      auto c_cls_model_ptr = new fastdeploy::vision::ocr::Classifier(
+          c_cls_model_file, c_cls_params_file, c_cls_option);
+      if (c_cls_enable_record_time_of_runtime) {
+        c_cls_model_ptr->EnableRecordTimeOfRuntime();
+      }
+      auto c_ppocr_pipeline_ptr = new fastdeploy::pipeline::PPOCRv3(
+          c_det_model_ptr, c_cls_model_ptr, c_rec_model_ptr);
+      // PP-OCRv3 handler with cls model
+      auto c_ppocr_handler_ptr = new fastdeploy::jni::pipeline::PPOCRHandler(
+          c_det_model_ptr, c_cls_model_ptr, c_rec_model_ptr, c_ppocr_pipeline_ptr);
+      c_ppocr_handler_ptr->SetPPOCRVersion(c_ocr_version_tag);
+      // WARN: need to release manually in Java !
+      return reinterpret_cast<jlong>(c_ppocr_handler_ptr);  // native handler context
+    } else {
+      auto c_ppocr_pipeline_ptr = new fastdeploy::pipeline::PPOCRv3(
+          c_det_model_ptr, c_rec_model_ptr);
+      // PP-OCRv3 handler without cls model
+      auto c_ppocr_handler_ptr = new fastdeploy::jni::pipeline::PPOCRHandler(
+          c_det_model_ptr, c_rec_model_ptr, c_ppocr_pipeline_ptr);
+      c_ppocr_handler_ptr->SetPPOCRVersion(c_ocr_version_tag);
+      // WARN: need to release manually in Java !
+      return reinterpret_cast<jlong>(c_ppocr_handler_ptr);  // native handler context
+    }
+  }
+  return 0;
+}
+
+JNIEXPORT jlong JNICALL
+Java_com_baidu_paddle_fastdeploy_pipeline_PPOCRBase_predictNative(
+    JNIEnv *env, jobject thiz, jlong native_handler_context,
+    jobject argb8888_bitmap, jboolean saved, jstring saved_image_path,
+    jboolean rendering) {
+  if (native_handler_context == 0) {
+    return 0;
+  }
+  cv::Mat c_bgr;
+  auto t = fastdeploy::jni::GetCurrentTime();
+  if (!fastdeploy::jni::ARGB888Bitmap2BGR(env, argb8888_bitmap, &c_bgr)) {
+    return 0;
+  }
+  LOGD("Read from bitmap costs %f ms", fastdeploy::jni::GetElapsedTime(t));
+  auto c_ppocr_handler_ptr = reinterpret_cast<fastdeploy::jni::pipeline::PPOCRHandler*>(
+      native_handler_context);
+  auto c_result_ptr = new fastdeploy::vision::OCRResult();
+  t = fastdeploy::jni::GetCurrentTime();
+  if (!c_ppocr_handler_ptr->Predict(&c_bgr, c_result_ptr)) {
+    delete c_result_ptr;
+    return 0;
+  }
+  LOGD("Predict from native costs %f ms", fastdeploy::jni::GetElapsedTime(t));
+  // DEBUG: show result
+  LOGD("Result: %s", c_result_ptr->Str().c_str());
+  c_ppocr_handler_ptr->PrintPPOCRHandlerTimeOfRuntime();
+  if (!c_result_ptr->boxes.empty() && rendering) {
+    t = fastdeploy::jni::GetCurrentTime();
+    auto c_vis_im = fastdeploy::vision::VisOcr(c_bgr, *(c_result_ptr));
+    LOGD("Visualize from native costs %f ms", fastdeploy::jni::GetElapsedTime(t));
+    // Rendering to bitmap
+    t = fastdeploy::jni::GetCurrentTime();
+    if (!fastdeploy::jni::BGR2ARGB888Bitmap(env, argb8888_bitmap, c_vis_im)) {
+      delete c_result_ptr;
+      return 0;
+    }
+    LOGD("Write to bitmap from native costs %f ms",
+         fastdeploy::jni::GetElapsedTime(t));
+    std::string c_saved_image_path =
+        fastdeploy::jni::ConvertTo<std::string>(env, saved_image_path);
+    if (!c_saved_image_path.empty() && saved) {
+      t = fastdeploy::jni::GetCurrentTime();
+      cv::imwrite(c_saved_image_path, c_vis_im);
+      LOGD("Save image from native costs %f ms, path: %s",
+           fastdeploy::jni::GetElapsedTime(t), c_saved_image_path.c_str());
+    }
+  }
+  // WARN: need to release it manually in Java !
+  return reinterpret_cast<jlong>(c_result_ptr);  // native result context
+}
+
+JNIEXPORT jboolean JNICALL
+Java_com_baidu_paddle_fastdeploy_pipeline_PPOCRBase_releaseNative(
+    JNIEnv *env, jobject thiz, jlong native_handler_context) {
+  if (native_handler_context == 0) {
+    return JNI_FALSE;
+  }
+  auto c_ppocr_handler_ptr = reinterpret_cast<fastdeploy::jni::pipeline::PPOCRHandler*>(
+      native_handler_context);
+  if (!c_ppocr_handler_ptr->ReleaseAllocatedOCRMemories()) {
+    delete c_ppocr_handler_ptr;
+    return JNI_FALSE;
+  }
+  delete c_ppocr_handler_ptr;
+  LOGD("[End] Release PPOCRHandler in native !");
+  return JNI_TRUE;
+}
+
+#ifdef __cplusplus
+}
+#endif
--- a/java/android/fastdeploy/src/main/cpp/vision/classification/paddleclas_model_jni.cc
+++ b/java/android/fastdeploy/src/main/cpp/vision/classification/paddleclas_model_jni.cc
@@ -22,7 +22,7 @@ extern "C" {

 JNIEXPORT jlong JNICALL
 Java_com_baidu_paddle_fastdeploy_vision_classification_PaddleClasModel_bindNative(
-    JNIEnv *env, jclass clazz, jstring model_file, jstring params_file,
+    JNIEnv *env, jobject thiz, jstring model_file, jstring params_file,
    jstring config_file, jint cpu_num_thread, jboolean enable_lite_fp16,
    jint lite_power_mode, jstring lite_optimized_model_dir,
    jboolean enable_record_time_of_runtime, jstring label_file) {
@@ -66,7 +66,7 @@ Java_com_baidu_paddle_fastdeploy_vision_classification_PaddleClasModel_bindNativ

 JNIEXPORT jlong JNICALL
 Java_com_baidu_paddle_fastdeploy_vision_classification_PaddleClasModel_predictNative(
-    JNIEnv *env, jclass clazz, jlong native_model_context,
+    JNIEnv *env, jobject thiz, jlong native_model_context,
    jobject argb8888_bitmap, jboolean saved, jstring saved_image_path,
    jfloat score_threshold, jboolean rendering) {
  if (native_model_context == 0) {
@@ -129,7 +129,7 @@ Java_com_baidu_paddle_fastdeploy_vision_classification_PaddleClasModel_predictNa

 JNIEXPORT jboolean JNICALL
 Java_com_baidu_paddle_fastdeploy_vision_classification_PaddleClasModel_releaseNative(
-    JNIEnv *env, jclass clazz, jlong native_model_context) {
+    JNIEnv *env, jobject thiz, jlong native_model_context) {
  auto c_model_ptr =
      reinterpret_cast<fastdeploy::vision::classification::PaddleClasModel *>(
          native_model_context);
--- a/java/android/fastdeploy/src/main/cpp/vision/detection/picodet_jni.cc
+++ b/java/android/fastdeploy/src/main/cpp/vision/detection/picodet_jni.cc
@@ -22,7 +22,7 @@ extern "C" {

 JNIEXPORT jlong JNICALL
 Java_com_baidu_paddle_fastdeploy_vision_detection_PicoDet_bindNative(
-    JNIEnv *env, jclass clazz, jstring model_file, jstring params_file,
+    JNIEnv *env, jobject thiz, jstring model_file, jstring params_file,
    jstring config_file, jint cpu_num_thread, jboolean enable_lite_fp16,
    jint lite_power_mode, jstring lite_optimized_model_dir,
    jboolean enable_record_time_of_runtime, jstring label_file) {
@@ -66,7 +66,7 @@ Java_com_baidu_paddle_fastdeploy_vision_detection_PicoDet_bindNative(

 JNIEXPORT jlong JNICALL
 Java_com_baidu_paddle_fastdeploy_vision_detection_PicoDet_predictNative(
-    JNIEnv *env, jclass clazz, jlong native_model_context,
+    JNIEnv *env, jobject thiz, jlong native_model_context,
    jobject argb8888_bitmap, jboolean saved, jstring saved_image_path,
    jfloat score_threshold, jboolean rendering) {
  if (native_model_context == 0) {
@@ -128,7 +128,7 @@ Java_com_baidu_paddle_fastdeploy_vision_detection_PicoDet_predictNative(

 JNIEXPORT jboolean JNICALL
 Java_com_baidu_paddle_fastdeploy_vision_detection_PicoDet_releaseNative(
-    JNIEnv *env, jclass clazz, jlong native_model_context) {
+    JNIEnv *env, jobject thiz, jlong native_model_context) {
  if (native_model_context == 0) {
    return JNI_FALSE;
  }
--- a/java/android/fastdeploy/src/main/cpp/vision/results_jni.cc
+++ b/java/android/fastdeploy/src/main/cpp/vision/results_jni.cc
@@ -25,7 +25,10 @@ extern "C" {
 /// Native DetectionResult for vision::DetectionResult.
 JNIEXPORT jint JNICALL
 Java_com_baidu_paddle_fastdeploy_vision_DetectionResult_copyBoxesNumFromNative(
-    JNIEnv *env, jclass clazz, jlong native_result_context) {
+    JNIEnv *env, jobject thiz, jlong native_result_context) {
+  if (native_result_context == 0) {
+    return 0;
+  }
  auto c_result_ptr = reinterpret_cast<fastdeploy::vision::DetectionResult *>(
      native_result_context);
  return static_cast<jint>(c_result_ptr->boxes.size());
@@ -33,7 +36,10 @@ Java_com_baidu_paddle_fastdeploy_vision_DetectionResult_copyBoxesNumFromNative(

 JNIEXPORT jfloatArray JNICALL
 Java_com_baidu_paddle_fastdeploy_vision_DetectionResult_copyBoxesFromNative(
-    JNIEnv *env, jclass clazz, jlong native_result_context) {
+    JNIEnv *env, jobject thiz, jlong native_result_context) {
+  if (native_result_context == 0) {
+    return {};
+  }
  auto c_result_ptr = reinterpret_cast<fastdeploy::vision::DetectionResult *>(
      native_result_context);
  if (c_result_ptr->boxes.empty()) {
@@ -50,7 +56,10 @@ Java_com_baidu_paddle_fastdeploy_vision_DetectionResult_copyBoxesFromNative(

 JNIEXPORT jfloatArray JNICALL
 Java_com_baidu_paddle_fastdeploy_vision_DetectionResult_copyScoresFromNative(
-    JNIEnv *env, jclass clazz, jlong native_result_context) {
+    JNIEnv *env, jobject thiz, jlong native_result_context) {
+  if (native_result_context == 0) {
+    return {};
+  }
  auto c_result_ptr = reinterpret_cast<fastdeploy::vision::DetectionResult *>(
      native_result_context);
  if (c_result_ptr->scores.empty()) {
@@ -63,7 +72,10 @@ Java_com_baidu_paddle_fastdeploy_vision_DetectionResult_copyScoresFromNative(

 JNIEXPORT jintArray JNICALL
 Java_com_baidu_paddle_fastdeploy_vision_DetectionResult_copyLabelIdsFromNative(
-    JNIEnv *env, jclass clazz, jlong native_result_context) {
+    JNIEnv *env, jobject thiz, jlong native_result_context) {
+  if (native_result_context == 0) {
+    return {};
+  }
  auto c_result_ptr = reinterpret_cast<fastdeploy::vision::DetectionResult *>(
      native_result_context);
  if (c_result_ptr->label_ids.empty()) {
@@ -76,7 +88,7 @@ Java_com_baidu_paddle_fastdeploy_vision_DetectionResult_copyLabelIdsFromNative(

 JNIEXPORT jboolean JNICALL
 Java_com_baidu_paddle_fastdeploy_vision_DetectionResult_releaseNative(
-    JNIEnv *env, jclass clazz, jlong native_result_context) {
+    JNIEnv *env, jobject thiz, jlong native_result_context) {
  if (native_result_context == 0) {
    return JNI_FALSE;
  }
@@ -90,7 +102,10 @@ Java_com_baidu_paddle_fastdeploy_vision_DetectionResult_releaseNative(
 /// Native ClassifyResult for vision::ClassifyResult.
 JNIEXPORT jfloatArray JNICALL
 Java_com_baidu_paddle_fastdeploy_vision_ClassifyResult_copyScoresFromNative(
-    JNIEnv *env, jclass clazz, jlong native_result_context) {
+    JNIEnv *env, jobject thiz, jlong native_result_context) {
+  if (native_result_context == 0) {
+    return {};
+  }
  auto c_result_ptr = reinterpret_cast<fastdeploy::vision::ClassifyResult *>(
      native_result_context);
  if (c_result_ptr->scores.empty()) {
@@ -103,7 +118,10 @@ Java_com_baidu_paddle_fastdeploy_vision_ClassifyResult_copyScoresFromNative(

 JNIEXPORT jintArray JNICALL
 Java_com_baidu_paddle_fastdeploy_vision_ClassifyResult_copyLabelIdsFromNative(
-    JNIEnv *env, jclass clazz, jlong native_result_context) {
+    JNIEnv *env, jobject thiz, jlong native_result_context) {
+  if (native_result_context == 0) {
+    return {};
+  }
  auto c_result_ptr = reinterpret_cast<fastdeploy::vision::ClassifyResult *>(
      native_result_context);
  if (c_result_ptr->label_ids.empty()) {
@@ -116,7 +134,7 @@ Java_com_baidu_paddle_fastdeploy_vision_ClassifyResult_copyLabelIdsFromNative(

 JNIEXPORT jboolean JNICALL
 Java_com_baidu_paddle_fastdeploy_vision_ClassifyResult_releaseNative(
-    JNIEnv *env, jclass clazz, jlong native_result_context) {
+    JNIEnv *env, jobject thiz, jlong native_result_context) {
  if (native_result_context == 0) {
    return JNI_FALSE;
  }
@@ -127,6 +145,123 @@ Java_com_baidu_paddle_fastdeploy_vision_ClassifyResult_releaseNative(
  return JNI_TRUE;
 }

+/// Native OCRResult for vision::OCRResult.
+JNIEXPORT jint JNICALL
+Java_com_baidu_paddle_fastdeploy_vision_OCRResult_copyBoxesNumFromNative(
+    JNIEnv *env, jobject thiz, jlong native_result_context) {
+  if (native_result_context == 0) {
+    return 0;
+  }
+  auto c_result_ptr = reinterpret_cast<fastdeploy::vision::OCRResult *>(
+      native_result_context);
+  return static_cast<jint>(c_result_ptr->boxes.size());
+}
+
+JNIEXPORT jintArray JNICALL
+Java_com_baidu_paddle_fastdeploy_vision_OCRResult_copyBoxesFromNative(
+    JNIEnv *env, jobject thiz, jlong native_result_context) {
+  if (native_result_context == 0) {
+    return {};
+  }
+  auto c_result_ptr = reinterpret_cast<fastdeploy::vision::OCRResult *>(
+      native_result_context);
+  if (c_result_ptr->boxes.empty()) {
+    return {};
+  }
+  const auto len = static_cast<int64_t>(c_result_ptr->boxes.size());
+  int buffer[len * 8];
+  const auto &boxes = c_result_ptr->boxes;
+  for (int64_t i = 0; i < len; ++i) {
+    std::memcpy((buffer + i * 8), (boxes.at(i).data()), 8 * sizeof(int));
+  }
+  return fastdeploy::jni::ConvertTo<jintArray>(env, buffer, len * 4);
+}
+
+JNIEXPORT jobjectArray JNICALL
+Java_com_baidu_paddle_fastdeploy_vision_OCRResult_copyTextFromNative(
+    JNIEnv *env, jobject thiz, jlong native_result_context) {
+  if (native_result_context == 0) {
+    return {};
+  }
+  auto c_result_ptr = reinterpret_cast<fastdeploy::vision::OCRResult *>(
+      native_result_context);
+  if (c_result_ptr->text.empty()) {
+    return {};
+  }
+  const auto len = static_cast<int64_t>(c_result_ptr->text.size());
+  jclass jstr_clazz = env->FindClass("java/lang/String");
+  jobjectArray jstr_array = env->NewObjectArray(
+      static_cast<jsize>(len), jstr_clazz,env->NewStringUTF(""));
+  for (int64_t i = 0; i < len; ++i) {
+    env->SetObjectArrayElement(jstr_array, static_cast<jsize>(i),
+                               fastdeploy::jni::ConvertTo<jstring>(
+                                   env, c_result_ptr->text.at(i)));
+  }
+  return jstr_array;
+}
+
+JNIEXPORT jfloatArray JNICALL
+Java_com_baidu_paddle_fastdeploy_vision_OCRResult_copyRecScoresFromNative(
+    JNIEnv *env, jobject thiz, jlong native_result_context) {
+  if (native_result_context == 0) {
+    return {};
+  }
+  auto c_result_ptr = reinterpret_cast<fastdeploy::vision::OCRResult *>(
+      native_result_context);
+  if (c_result_ptr->rec_scores.empty()) {
+    return {};
+  }
+  const auto len = static_cast<int64_t>(c_result_ptr->rec_scores.size());
+  const float *buffer = static_cast<float *>(c_result_ptr->rec_scores.data());
+  return fastdeploy::jni::ConvertTo<jfloatArray>(env, buffer, len);
+}
+
+JNIEXPORT jfloatArray JNICALL
+Java_com_baidu_paddle_fastdeploy_vision_OCRResult_copyClsScoresFromNative(
+    JNIEnv *env, jobject thiz, jlong native_result_context) {
+  if (native_result_context == 0) {
+    return {};
+  }
+  auto c_result_ptr = reinterpret_cast<fastdeploy::vision::OCRResult *>(
+      native_result_context);
+  if (c_result_ptr->cls_scores.empty()) {
+    return {};
+  }
+  const auto len = static_cast<int64_t>(c_result_ptr->cls_scores.size());
+  const float *buffer = static_cast<float *>(c_result_ptr->cls_scores.data());
+  return fastdeploy::jni::ConvertTo<jfloatArray>(env, buffer, len);
+}
+
+JNIEXPORT jintArray JNICALL
+Java_com_baidu_paddle_fastdeploy_vision_OCRResult_copyClsLabelsFromNative(
+    JNIEnv *env, jobject thiz, jlong native_result_context) {
+  if (native_result_context == 0) {
+    return {};
+  }
+  auto c_result_ptr = reinterpret_cast<fastdeploy::vision::OCRResult *>(
+      native_result_context);
+  if (c_result_ptr->cls_labels.empty()) {
+    return {};
+  }
+  const auto len = static_cast<int64_t>(c_result_ptr->cls_labels.size());
+  const int *buffer = static_cast<int *>(c_result_ptr->cls_labels.data());
+  return fastdeploy::jni::ConvertTo<jintArray>(env, buffer, len);
+}
+
+JNIEXPORT jboolean JNICALL
+Java_com_baidu_paddle_fastdeploy_vision_OCRResult_releaseNative(
+    JNIEnv *env, jobject thiz, jlong native_result_context) {
+  if (native_result_context == 0) {
+    return JNI_FALSE;
+  }
+  auto c_result_ptr = reinterpret_cast<fastdeploy::vision::OCRResult *>(
+      native_result_context);
+  delete c_result_ptr;
+  LOGD("Release OCRResult in native !");
+  return JNI_TRUE;
+}
+
 #ifdef __cplusplus
 }
 #endif
+
--- a/java/android/fastdeploy/src/main/cpp/vision/visualize_jni.cc
+++ b/java/android/fastdeploy/src/main/cpp/vision/visualize_jni.cc
@@ -19,6 +19,7 @@
 extern "C" {
 #endif

+/// VisDetection
 JNIEXPORT jboolean JNICALL
 Java_com_baidu_paddle_fastdeploy_vision_Visualize_visDetectionNative(
    JNIEnv *env, jclass clazz, jobject argb8888_bitmap, jobjectArray boxes,
@@ -32,6 +33,8 @@ Java_com_baidu_paddle_fastdeploy_vision_Visualize_visDetectionNative(
  }
  fastdeploy::vision::DetectionResult c_result;
  c_result.Resize(len);
+
+  // boxes [n,4]
  bool check_validation = true;
  for (int i = 0; i < len; ++i) {
    auto j_box =
@@ -48,18 +51,19 @@ Java_com_baidu_paddle_fastdeploy_vision_Visualize_visDetectionNative(
  if (!check_validation) {
    return JNI_FALSE;
  }
+  // scores [n]
  jfloat *j_scores_ptr = env->GetFloatArrayElements(scores, nullptr);
  std::memcpy(c_result.scores.data(), j_scores_ptr, len * sizeof(float));
  env->ReleaseFloatArrayElements(scores, j_scores_ptr, 0);
+  // label_ids [n]
  jint *j_label_ids_ptr = env->GetIntArrayElements(label_ids, nullptr);
  std::memcpy(c_result.label_ids.data(), j_label_ids_ptr, len * sizeof(int));
  env->ReleaseIntArrayElements(label_ids, j_label_ids_ptr, 0);

-  // Get labels from Java
+  // Get labels from Java [n]
  std::vector<std::string> c_labels;
  int label_len = env->GetArrayLength(labels);
  if (label_len > 0) {
-    c_labels.reserve(label_len);
    for (int i = 0; i < label_len; ++i) {
      auto j_str =
          reinterpret_cast<jstring>(env->GetObjectArrayElement(labels, i));
@@ -87,6 +91,158 @@ Java_com_baidu_paddle_fastdeploy_vision_Visualize_visDetectionNative(
  return JNI_TRUE;
 }

+/// VisClassification
+JNIEXPORT jboolean JNICALL
+Java_com_baidu_paddle_fastdeploy_vision_Visualize_visClassificationNative(
+    JNIEnv *env, jclass clazz, jobject argb8888_bitmap, jfloatArray scores,
+    jintArray label_ids, jfloat score_threshold, jfloat font_size,
+    jobjectArray labels) {
+  // Draw ClassifyResult to ARGB8888 Bitmap
+  int len = env->GetArrayLength(scores);
+  if ((len == 0) || (len != env->GetArrayLength(label_ids))) {
+    return JNI_FALSE;
+  }
+  fastdeploy::vision::ClassifyResult c_result;
+  c_result.scores.resize(len);
+  c_result.label_ids.resize(len);
+  // scores [n]
+  jfloat *j_scores_ptr = env->GetFloatArrayElements(scores, nullptr);
+  std::memcpy(c_result.scores.data(), j_scores_ptr, len * sizeof(float));
+  env->ReleaseFloatArrayElements(scores, j_scores_ptr, 0);
+  // label_ids [n]
+  jint *j_label_ids_ptr = env->GetIntArrayElements(label_ids, nullptr);
+  std::memcpy(c_result.label_ids.data(), j_label_ids_ptr, len * sizeof(int));
+  env->ReleaseIntArrayElements(label_ids, j_label_ids_ptr, 0);
+
+  // Get labels from Java [n]
+  std::vector<std::string> c_labels;
+  int label_len = env->GetArrayLength(labels);
+  if (label_len > 0) {
+    for (int i = 0; i < label_len; ++i) {
+      auto j_str =
+          reinterpret_cast<jstring>(env->GetObjectArrayElement(labels, i));
+      c_labels.push_back(fastdeploy::jni::ConvertTo<std::string>(env, j_str));
+    }
+  }
+  cv::Mat c_bgr;
+  // From ARGB Bitmap to BGR
+  if (!fastdeploy::jni::ARGB888Bitmap2BGR(env, argb8888_bitmap, &c_bgr)) {
+    return JNI_FALSE;
+  }
+  cv::Mat c_vis_im;
+  if (!c_labels.empty()) {
+    c_vis_im = fastdeploy::vision::VisClassification(
+        c_bgr, c_result, c_labels, 5, score_threshold, font_size);
+  } else {
+    c_vis_im = fastdeploy::vision::VisClassification(
+        c_bgr, c_result, 5, score_threshold, font_size);
+  }
+  // Rendering to bitmap
+  if (!fastdeploy::jni::BGR2ARGB888Bitmap(env, argb8888_bitmap, c_vis_im)) {
+    return JNI_FALSE;
+  }
+  return JNI_TRUE;
+}
+
+/// VisOcr
+JNIEXPORT jboolean JNICALL
+Java_com_baidu_paddle_fastdeploy_vision_Visualize_visOcrNative(
+    JNIEnv *env, jclass clazz, jobject argb8888_bitmap,
+    jobjectArray boxes, jobjectArray text, jfloatArray rec_scores,
+    jfloatArray cls_scores, jintArray cls_labels) {
+  // Draw OCRResult to ARGB8888 Bitmap
+  int len = env->GetArrayLength(boxes);
+  if ((len == 0) || (len != env->GetArrayLength(text)) ||
+      (len != env->GetArrayLength(rec_scores)) ||
+      (len != env->GetArrayLength(cls_scores)) ||
+      (len != env->GetArrayLength(cls_labels))) {
+    return JNI_FALSE;
+  }
+  fastdeploy::vision::OCRResult c_result;
+  c_result.boxes.resize(len);
+  c_result.rec_scores.resize(len);
+  c_result.cls_scores.resize(len);
+  c_result.cls_labels.resize(len);
+
+  // boxes [n,8]
+  bool check_validation = true;
+  for (int i = 0; i < len; ++i) {
+    auto j_box =
+        reinterpret_cast<jintArray>(env->GetObjectArrayElement(boxes, i));
+    if (env->GetArrayLength(j_box) == 8) {
+      jint *j_box_ptr = env->GetIntArrayElements(j_box, nullptr);
+      std::memcpy(c_result.boxes[i].data(), j_box_ptr, 8 * sizeof(int));
+      env->ReleaseIntArrayElements(j_box, j_box_ptr, 0);
+    } else {
+      check_validation = false;
+      break;
+    }
+  }
+  if (!check_validation) {
+    return JNI_FALSE;
+  }
+
+  // text [n]
+  int text_len = env->GetArrayLength(text);
+  if (text_len > 0) {
+    for (int i = 0; i < text_len; ++i) {
+      auto j_str =
+          reinterpret_cast<jstring>(env->GetObjectArrayElement(text, i));
+      c_result.text.push_back(fastdeploy::jni::ConvertTo<std::string>(env, j_str));
+    }
+  }
+
+  // rec_scores [n]
+  jfloat *j_rec_scores_ptr = env->GetFloatArrayElements(rec_scores, nullptr);
+  std::memcpy(c_result.rec_scores.data(), j_rec_scores_ptr, len * sizeof(float));
+  env->ReleaseFloatArrayElements(rec_scores, j_rec_scores_ptr, 0);
+  // cls_scores [n]
+  jfloat *j_cls_scores_ptr = env->GetFloatArrayElements(cls_scores, nullptr);
+  std::memcpy(c_result.cls_scores.data(), j_cls_scores_ptr, len * sizeof(float));
+  env->ReleaseFloatArrayElements(cls_scores, j_cls_scores_ptr, 0);
+  // cls_labels [n]
+  jint *j_cls_label_ptr = env->GetIntArrayElements(cls_labels, nullptr);
+  std::memcpy(c_result.cls_labels.data(), j_cls_label_ptr, len * sizeof(int));
+  env->ReleaseIntArrayElements(cls_labels, j_cls_label_ptr, 0);
+
+  cv::Mat c_bgr;
+  // From ARGB Bitmap to BGR
+  if (!fastdeploy::jni::ARGB888Bitmap2BGR(env, argb8888_bitmap, &c_bgr)) {
+    return JNI_FALSE;
+  }
+  auto c_vis_im = fastdeploy::vision::VisOcr(c_bgr, c_result);
+  // Rendering to bitmap
+  if (!fastdeploy::jni::BGR2ARGB888Bitmap(env, argb8888_bitmap, c_vis_im)) {
+    return JNI_FALSE;
+  }
+  return JNI_TRUE;
+}
+
 #ifdef __cplusplus
 }
 #endif
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
--- a/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/pipeline/PPOCRBase.java
+++ b/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/pipeline/PPOCRBase.java
@@ -0,0 +1,195 @@
+package com.baidu.paddle.fastdeploy.pipeline;
+
+import android.graphics.Bitmap;
+
+import com.baidu.paddle.fastdeploy.FastDeployInitializer;
+import com.baidu.paddle.fastdeploy.vision.OCRResult;
+import com.baidu.paddle.fastdeploy.vision.ocr.DBDetector;
+import com.baidu.paddle.fastdeploy.vision.ocr.Classifier;
+import com.baidu.paddle.fastdeploy.vision.ocr.Recognizer;
+
+public class PPOCRBase {
+    protected long mNativeHandlerContext = 0; // Context from native.
+    protected boolean mInitialized = false;
+
+    public PPOCRBase() {
+        mInitialized = false;
+    }
+
+    // Constructor w/o classifier
+    public PPOCRBase(DBDetector detModel,
+                     Recognizer recModel,
+                     PPOCRVersion OCRVersionTag) {
+        init_(detModel, new Classifier(), recModel, OCRVersionTag);
+    }
+
+    public PPOCRBase(DBDetector detModel,
+                     Classifier clsModel,
+                     Recognizer recModel,
+                     PPOCRVersion OCRVersionTag) {
+        init_(detModel, clsModel, recModel, OCRVersionTag);
+    }
+
+    // Call init manually w/o classifier
+    public boolean init(DBDetector detModel,
+                        Recognizer recModel,
+                        PPOCRVersion OCRVersionTag) {
+        return init_(detModel, new Classifier(), recModel, OCRVersionTag);
+    }
+
+    public boolean init(DBDetector detModel,
+                        Classifier clsModel,
+                        Recognizer recModel,
+                        PPOCRVersion OCRVersionTag) {
+        return init_(detModel, clsModel, recModel, OCRVersionTag);
+    }
+
+    public boolean release() {
+        mInitialized = false;
+        if (mNativeHandlerContext == 0) {
+            return false;
+        }
+        return releaseNative(mNativeHandlerContext);
+    }
+
+    public boolean initialized() {
+        return mInitialized;
+    }
+
+    // Predict without image saving and bitmap rendering.
+    public OCRResult predict(Bitmap ARGB8888Bitmap) {
+        if (mNativeHandlerContext == 0) {
+            return new OCRResult();
+        }
+        // Only support ARGB8888 bitmap in native now.
+        return new OCRResult(predictNative(
+                mNativeHandlerContext, ARGB8888Bitmap, false,
+                "", false));
+    }
+
+    // Predict with image saving and bitmap rendering (will cost more times)
+    public OCRResult predict(Bitmap ARGB8888Bitmap,
+                             String savedImagePath) {
+        // scoreThreshold is for visualizing only.
+        if (mNativeHandlerContext == 0) {
+            return new OCRResult();
+        }
+        // Only support ARGB8888 bitmap in native now.
+        return new OCRResult(predictNative(
+                mNativeHandlerContext, ARGB8888Bitmap, true,
+                savedImagePath, true));
+    }
+
+    public boolean init_(DBDetector detModel,
+                         Classifier clsModel,
+                         Recognizer recModel,
+                         PPOCRVersion OCRVersionTag) {
+        if (!mInitialized) {
+            mNativeHandlerContext = bindNative(
+                    OCRVersionTag.ordinal(),
+                    detModel.mModelFile,
+                    detModel.mParamsFile,
+                    clsModel.mModelFile,
+                    clsModel.mParamsFile,
+                    recModel.mModelFile,
+                    recModel.mParamsFile,
+                    recModel.mLabelPath,
+                    detModel.mRuntimeOption.mCpuThreadNum,
+                    clsModel.mRuntimeOption.mCpuThreadNum,
+                    recModel.mRuntimeOption.mCpuThreadNum,
+                    detModel.mRuntimeOption.mEnableLiteFp16,
+                    clsModel.mRuntimeOption.mEnableLiteFp16,
+                    recModel.mRuntimeOption.mEnableLiteFp16,
+                    detModel.mRuntimeOption.mLitePowerMode.ordinal(),
+                    clsModel.mRuntimeOption.mLitePowerMode.ordinal(),
+                    recModel.mRuntimeOption.mLitePowerMode.ordinal(),
+                    detModel.mRuntimeOption.mLiteOptimizedModelDir,
+                    clsModel.mRuntimeOption.mLiteOptimizedModelDir,
+                    recModel.mRuntimeOption.mLiteOptimizedModelDir,
+                    detModel.mRuntimeOption.mEnableRecordTimeOfRuntime,
+                    clsModel.mRuntimeOption.mEnableRecordTimeOfRuntime,
+                    recModel.mRuntimeOption.mEnableRecordTimeOfRuntime,
+                    clsModel.initialized());
+            if (mNativeHandlerContext != 0) {
+                mInitialized = true;
+            }
+            return mInitialized;
+        } else {
+            // release current native context and bind a new one.
+            if (release()) {
+                mNativeHandlerContext = bindNative(
+                        OCRVersionTag.ordinal(),
+                        detModel.mModelFile,
+                        detModel.mParamsFile,
+                        clsModel.mModelFile,
+                        clsModel.mParamsFile,
+                        recModel.mModelFile,
+                        recModel.mParamsFile,
+                        recModel.mLabelPath,
+                        detModel.mRuntimeOption.mCpuThreadNum,
+                        clsModel.mRuntimeOption.mCpuThreadNum,
+                        recModel.mRuntimeOption.mCpuThreadNum,
+                        detModel.mRuntimeOption.mEnableLiteFp16,
+                        clsModel.mRuntimeOption.mEnableLiteFp16,
+                        recModel.mRuntimeOption.mEnableLiteFp16,
+                        detModel.mRuntimeOption.mLitePowerMode.ordinal(),
+                        clsModel.mRuntimeOption.mLitePowerMode.ordinal(),
+                        recModel.mRuntimeOption.mLitePowerMode.ordinal(),
+                        detModel.mRuntimeOption.mLiteOptimizedModelDir,
+                        clsModel.mRuntimeOption.mLiteOptimizedModelDir,
+                        recModel.mRuntimeOption.mLiteOptimizedModelDir,
+                        detModel.mRuntimeOption.mEnableRecordTimeOfRuntime,
+                        clsModel.mRuntimeOption.mEnableRecordTimeOfRuntime,
+                        recModel.mRuntimeOption.mEnableRecordTimeOfRuntime,
+                        clsModel.initialized());
+                if (mNativeHandlerContext != 0) {
+                    mInitialized = true;
+                }
+                return mInitialized;
+            }
+            return false;
+        }
+    }
+
+    // Bind predictor from native context.
+    private native long bindNative(int PPOCRVersionTag,
+                                   String detModelFile,
+                                   String detParamsFile,
+                                   String clsModelFile,
+                                   String clsParamsFile,
+                                   String recModelFile,
+                                   String recParamsFile,
+                                   String recLabelPath,
+                                   int detCpuNumThread,
+                                   int clsCpuNumThread,
+                                   int recCpuNumThread,
+                                   boolean detEnableLiteFp16,
+                                   boolean clsEnableLiteFp16,
+                                   boolean recEnableLiteFp16,
+                                   int detLitePowerMode,
+                                   int clsLitePowerMode,
+                                   int recLitePowerMode,
+                                   String detLiteOptimizedModelDir,
+                                   String clsLiteOptimizedModelDir,
+                                   String recLiteOptimizedModelDir,
+                                   boolean detEnableRecordTimeOfRuntime,
+                                   boolean clsEnableRecordTimeOfRuntime,
+                                   boolean recEnableRecordTimeOfRuntime,
+                                   boolean haveClsModel);
+
+    // Call prediction from native context.
+    private native long predictNative(long nativeHandlerContext,
+                                      Bitmap ARGB8888Bitmap,
+                                      boolean saved,
+                                      String savedImagePath,
+                                      boolean rendering);
+
+    // Release buffers allocated in native context.
+    private native boolean releaseNative(long nativeHandlerContext);
+
+    // Initializes at the beginning.
+    static {
+        FastDeployInitializer.init();
+    }
+
+}
--- a/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/pipeline/PPOCRVersion.java
+++ b/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/pipeline/PPOCRVersion.java
@@ -0,0 +1,7 @@
+package com.baidu.paddle.fastdeploy.pipeline;
+
+public enum PPOCRVersion {
+    OCR_V1,
+    OCR_V2,
+    OCR_V3
+}
--- a/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/pipeline/PPOCRv2.java
+++ b/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/pipeline/PPOCRv2.java
@@ -0,0 +1,61 @@
+package com.baidu.paddle.fastdeploy.pipeline;
+
+import com.baidu.paddle.fastdeploy.vision.ocr.Classifier;
+import com.baidu.paddle.fastdeploy.vision.ocr.DBDetector;
+import com.baidu.paddle.fastdeploy.vision.ocr.Recognizer;
+
+public class PPOCRv2 extends PPOCRBase {
+    public PPOCRv2() {
+        super();
+    }
+
+    // Constructor w/o classifier
+    public PPOCRv2(DBDetector detModel,
+                   Recognizer recModel) {
+        super(detModel, recModel, PPOCRVersion.OCR_V2);
+    }
+
+    public PPOCRv2(DBDetector detModel,
+                   Classifier clsModel,
+                   Recognizer recModel) {
+        super(detModel, clsModel, recModel, PPOCRVersion.OCR_V2);
+    }
+
+    // Call init manually w/o classifier
+    public boolean init(DBDetector detModel,
+                        Recognizer recModel) {
+        return init(detModel, recModel, PPOCRVersion.OCR_V2);
+    }
+
+    public boolean init(DBDetector detModel,
+                        Classifier clsModel,
+                        Recognizer recModel) {
+        return init(detModel, clsModel, recModel, PPOCRVersion.OCR_V2);
+    }
+}
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
--- a/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/pipeline/PPOCRv3.java
+++ b/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/pipeline/PPOCRv3.java
@@ -0,0 +1,36 @@
+package com.baidu.paddle.fastdeploy.pipeline;
+
+import com.baidu.paddle.fastdeploy.vision.ocr.Classifier;
+import com.baidu.paddle.fastdeploy.vision.ocr.DBDetector;
+import com.baidu.paddle.fastdeploy.vision.ocr.Recognizer;
+
+public class PPOCRv3 extends PPOCRBase {
+    public PPOCRv3() {
+        super();
+    }
+
+    // Constructor w/o classifier
+    public PPOCRv3(DBDetector detModel,
+                   Recognizer recModel) {
+        super(detModel, recModel, PPOCRVersion.OCR_V3);
+    }
+
+    public PPOCRv3(DBDetector detModel,
+                   Classifier clsModel,
+                   Recognizer recModel) {
+        super(detModel, clsModel, recModel, PPOCRVersion.OCR_V3);
+    }
+
+    // Call init manually w/o classifier
+    public boolean init(DBDetector detModel,
+                        Recognizer recModel) {
+        return init(detModel, recModel, PPOCRVersion.OCR_V3);
+    }
+
+    public boolean init(DBDetector detModel,
+                        Classifier clsModel,
+                        Recognizer recModel) {
+        return init(detModel, clsModel, recModel, PPOCRVersion.OCR_V3);
+    }
+}
+
--- a/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/ClassifyResult.java
+++ b/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/ClassifyResult.java
@@ -42,10 +42,10 @@ public class ClassifyResult {
    }

    // Fetch native buffers from native context.
-    private static native float[] copyScoresFromNative(long nativeResultContext);
+    private native float[] copyScoresFromNative(long nativeResultContext);

-    private static native int[] copyLabelIdsFromNative(long nativeResultContext);
+    private native int[] copyLabelIdsFromNative(long nativeResultContext);

-    private static native boolean releaseNative(long nativeResultContext);
+    private native boolean releaseNative(long nativeResultContext);

 }
--- a/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/DetectionResult.java
+++ b/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/DetectionResult.java
@@ -63,15 +63,15 @@ public class DetectionResult {
    }

    // Fetch native buffers from native context.
-    private static native int copyBoxesNumFromNative(long nativeResultContext);
+    private native int copyBoxesNumFromNative(long nativeResultContext);

-    private static native float[] copyBoxesFromNative(long nativeResultContext);
+    private native float[] copyBoxesFromNative(long nativeResultContext);

-    private static native float[] copyScoresFromNative(long nativeResultContext);
+    private native float[] copyScoresFromNative(long nativeResultContext);

-    private static native int[] copyLabelIdsFromNative(long nativeResultContext);
+    private native int[] copyLabelIdsFromNative(long nativeResultContext);

-    private static native boolean releaseNative(long nativeResultContext);
+    private native boolean releaseNative(long nativeResultContext);

    // Initializes at the beginning.
    static {
--- a/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/OCRResult.java
+++ b/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/OCRResult.java
@@ -0,0 +1,99 @@
+package com.baidu.paddle.fastdeploy.vision;
+
+import android.support.annotation.NonNull;
+
+import com.baidu.paddle.fastdeploy.FastDeployInitializer;
+
+import java.util.Arrays;
+
+public class OCRResult {
+    public int[][] mBoxes;  // [n,8]
+    public String[] mText;  // [n]
+    public float[] mRecScores;  // [n]
+    public float[] mClsScores;  // [n]
+    public int[] mClsLabels;  // [n]
+    public boolean mInitialized = false;
+
+    public OCRResult() {
+        mInitialized = false;
+    }
+
+    public OCRResult(long nativeResultContext) {
+        mInitialized = copyAllFromNativeContext(nativeResultContext);
+    }
+
+    public boolean initialized() {
+        return mInitialized;
+    }
+
+    // Setup results from native buffers.
+    private boolean copyAllFromNativeContext(long nativeResultContext) {
+        if (nativeResultContext == 0) {
+            return false;
+        }
+        if (copyBoxesNumFromNative(nativeResultContext) > 0) {
+            setBoxes(copyBoxesFromNative(nativeResultContext));
+            setText(copyTextFromNative(nativeResultContext));
+            setRecScores(copyRecScoresFromNative(nativeResultContext));
+            setClsScores(copyClsScoresFromNative(nativeResultContext));
+            setClsLabels(copyClsLabelsFromNative(nativeResultContext));
+        }
+        // WARN: must release ctx.
+        return releaseNative(nativeResultContext);
+    }
+
+    private void setBoxes(@NonNull int[] boxesBuffer) {
+        int boxesNum = boxesBuffer.length / 8;
+        if (boxesNum > 0) {
+            mBoxes = new int[boxesNum][8];
+            for (int i = 0; i < boxesNum; ++i) {
+                mBoxes[i] = Arrays.copyOfRange(
+                        boxesBuffer, i * 8, (i + 1) * 8);
+            }
+        }
+    }
+
+    private void setText(@NonNull String[] textBuffer) {
+        if (textBuffer.length > 0) {
+            mText = textBuffer.clone();
+        }
+    }
+
+    private void setRecScores(@NonNull float[] recScoresBuffer) {
+        if (recScoresBuffer.length > 0) {
+            mRecScores = recScoresBuffer.clone();
+        }
+    }
+
+    private void setClsScores(@NonNull float[] clsScoresBuffer) {
+        if (clsScoresBuffer.length > 0) {
+            mClsScores = clsScoresBuffer.clone();
+        }
+    }
+
+    private void setClsLabels(@NonNull int[] clsLabelBuffer) {
+        if (clsLabelBuffer.length > 0) {
+            mClsLabels = clsLabelBuffer.clone();
+        }
+    }
+
+    // Fetch native buffers from native context.
+    private native int copyBoxesNumFromNative(long nativeResultContext);
+
+    private native int[] copyBoxesFromNative(long nativeResultContext);
+
+    private native String[] copyTextFromNative(long nativeResultContext);
+
+    private native float[] copyRecScoresFromNative(long nativeResultContext);
+
+    private native float[] copyClsScoresFromNative(long nativeResultContext);
+
+    private native int[] copyClsLabelsFromNative(long nativeResultContext);
+
+    private native boolean releaseNative(long nativeResultContext);
+
+    // Initializes at the beginning.
+    static {
+        FastDeployInitializer.init();
+    }
+}
--- a/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/Visualize.java
+++ b/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/Visualize.java
@@ -52,10 +52,10 @@ public class Visualize {

    public static boolean visDetection(Bitmap ARGB8888Bitmap,
                                       DetectionResult result,
+                                       String[] labels,
                                       float score_threshold,
                                       int line_size,
-                                       float font_size,
-                                       String[] labels) {
+                                       float font_size) {
        return visDetectionNative(
                ARGB8888Bitmap,
                result.mBoxes,
@@ -67,8 +67,74 @@ public class Visualize {
                labels);
    }

+    // Visualize ClassifyResult without labels
+    public static boolean visClassification(Bitmap ARGB8888Bitmap,
+                                            ClassifyResult result) {
+        return visClassificationNative(
+                ARGB8888Bitmap,
+                result.mScores,
+                result.mLabelIds,
+                0.f, 1,
+                new String[]{});
+
+    }
+
+    public static boolean visClassification(Bitmap ARGB8888Bitmap,
+                                            ClassifyResult result,
+                                            float score_threshold,
+                                            float font_size) {
+        return visClassificationNative(
+                ARGB8888Bitmap,
+                result.mScores,
+                result.mLabelIds,
+                score_threshold,
+                font_size,
+                new String[]{});
+
+    }
+
+    // Visualize ClassifyResult with labels
+    public static boolean visClassification(Bitmap ARGB8888Bitmap,
+                                            ClassifyResult result,
+                                            String[] labels) {
+        return visClassificationNative(
+                ARGB8888Bitmap,
+                result.mScores,
+                result.mLabelIds,
+                0.f, 1,
+                labels);
+
+    }
+
+    public static boolean visClassification(Bitmap ARGB8888Bitmap,
+                                            ClassifyResult result,
+                                            String[] labels,
+                                            float score_threshold,
+                                            float font_size) {
+        return visClassificationNative(
+                ARGB8888Bitmap,
+                result.mScores,
+                result.mLabelIds,
+                score_threshold,
+                font_size,
+                labels);
+
+    }
+
+    // Visualize OCRResult
+    public static boolean visOcr(Bitmap ARGB8888Bitmap,
+                                 OCRResult result) {
+        return visOcrNative(
+                ARGB8888Bitmap,
+                result.mBoxes,
+                result.mText,
+                result.mRecScores,
+                result.mClsScores,
+                result.mClsLabels);
+    }
+
    // VisDetection in native
-    public static native boolean visDetectionNative(Bitmap ARGB8888Bitmap,
+    private static native boolean visDetectionNative(Bitmap ARGB8888Bitmap,
                                                     float[][] boxes,
                                                     float[] scores,
                                                     int[] labelIds,
@@ -77,6 +143,22 @@ public class Visualize {
                                                     float font_size,
                                                     String[] labels);

+    // VisClassification in native
+    private static native boolean visClassificationNative(Bitmap ARGB8888Bitmap,
+                                                          float[] scores,
+                                                          int[] labelIds,
+                                                          float score_threshold,
+                                                          float font_size,
+                                                          String[] labels);
+
+    // VisOCRResult in native
+    private static native boolean visOcrNative(Bitmap ARGB8888Bitmap,
+                                               int[][] boxes,
+                                               String[] text,
+                                               float[] recScores,
+                                               float[] clsScores,
+                                               int[] clsLabels);
+

    /* Initializes at the beginning */
    static {
--- a/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/classification/PaddleClasModel.java
+++ b/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/classification/PaddleClasModel.java
@@ -143,7 +143,7 @@ public class PaddleClasModel {


    // Bind predictor from native context.
-    private static native long bindNative(String modelFile,
+    private native long bindNative(String modelFile,
                                   String paramsFile,
                                   String configFile,
                                   int cpuNumThread,
@@ -154,7 +154,7 @@ public class PaddleClasModel {
                                   String labelFile);

    // Call prediction from native context.
-    private static native long predictNative(long nativeModelContext,
+    private native long predictNative(long nativeModelContext,
                                      Bitmap ARGB8888Bitmap,
                                      boolean saved,
                                      String savedImagePath,
@@ -162,7 +162,7 @@ public class PaddleClasModel {
                                      boolean rendering);

    // Release buffers allocated in native context.
-    private static native boolean releaseNative(long nativeModelContext);
+    private native boolean releaseNative(long nativeModelContext);

    // Initializes at the beginning.
    static {
--- a/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/detection/PicoDet.java
+++ b/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/detection/PicoDet.java
@@ -141,7 +141,7 @@ public class PicoDet {
    }

    // Bind predictor from native context.
-    private static native long bindNative(String modelFile,
+    private native long bindNative(String modelFile,
                                   String paramsFile,
                                   String configFile,
                                   int cpuNumThread,
@@ -152,7 +152,7 @@ public class PicoDet {
                                   String labelFile);

    // Call prediction from native context.
-    private static native long predictNative(long nativeModelContext,
+    private native long predictNative(long nativeModelContext,
                                      Bitmap ARGB8888Bitmap,
                                      boolean saved,
                                      String savedImagePath,
@@ -160,7 +160,7 @@ public class PicoDet {
                                      boolean rendering);

    // Release buffers allocated in native context.
-    private static native boolean releaseNative(long nativeModelContext);
+    private native boolean releaseNative(long nativeModelContext);

    // Initializes at the beginning.
    static {
--- a/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/ocr/Classifier.java
+++ b/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/ocr/Classifier.java
@@ -0,0 +1,41 @@
+package com.baidu.paddle.fastdeploy.vision.ocr;
+
+import com.baidu.paddle.fastdeploy.RuntimeOption;
+
+public class Classifier {
+    // TODO(qiuyanjun): Allows users to set model parameters,
+    //  such as cls_thresh, cls_image_shape, is_scale, etc.
+    //  These parameters should be passed in via JNI.
+    public String mModelFile;
+    public String mParamsFile;
+    public RuntimeOption mRuntimeOption;
+    public boolean mInitialized = false;
+
+    public Classifier() {
+        mModelFile = "";
+        mParamsFile = "";
+        mRuntimeOption = new RuntimeOption();
+        mInitialized = false;
+    }
+
+    public Classifier(String modelFile,
+                      String paramsFile) {
+        mModelFile = modelFile;
+        mParamsFile = paramsFile;
+        mRuntimeOption = new RuntimeOption();
+        mInitialized = true;
+    }
+
+    public Classifier(String modelFile,
+                      String paramsFile,
+                      RuntimeOption option) {
+        mModelFile = modelFile;
+        mParamsFile = paramsFile;
+        mRuntimeOption = option;
+        mInitialized = true;
+    }
+
+    public boolean initialized() {
+        return mInitialized;
+    }
+}
--- a/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/ocr/DBDetector.java
+++ b/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/ocr/DBDetector.java
@@ -0,0 +1,41 @@
+package com.baidu.paddle.fastdeploy.vision.ocr;
+
+import com.baidu.paddle.fastdeploy.RuntimeOption;
+
+public class DBDetector {
+    // TODO(qiuyanjun): Allows users to set model parameters,
+    //  such as det_db_box_thresh, det_db_thresh, use_dilation, etc.
+    //  These parameters should be passed in via JNI.
+    public String mModelFile;
+    public String mParamsFile;
+    public RuntimeOption mRuntimeOption;
+    public boolean mInitialized = false;
+
+    public DBDetector() {
+        mModelFile = "";
+        mParamsFile = "";
+        mRuntimeOption = new RuntimeOption();
+        mInitialized = false;
+    }
+
+    public DBDetector(String modelFile,
+                      String paramsFile) {
+        mModelFile = modelFile;
+        mParamsFile = paramsFile;
+        mRuntimeOption = new RuntimeOption();
+        mInitialized = true;
+    }
+
+    public DBDetector(String modelFile,
+                      String paramsFile,
+                      RuntimeOption option) {
+        mModelFile = modelFile;
+        mParamsFile = paramsFile;
+        mRuntimeOption = option;
+        mInitialized = true;
+    }
+
+    public boolean initialized() {
+        return mInitialized;
+    }
+}
--- a/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/ocr/Recognizer.java
+++ b/java/android/fastdeploy/src/main/java/com/baidu/paddle/fastdeploy/vision/ocr/Recognizer.java
@@ -0,0 +1,47 @@
+package com.baidu.paddle.fastdeploy.vision.ocr;
+
+import com.baidu.paddle.fastdeploy.RuntimeOption;
+
+public class Recognizer {
+    // TODO(qiuyanjun): Allows users to set model parameters,
+    //  such as rec_img_h, rec_img_w, rec_image_shape, etc.
+    //  These parameters should be passed in via JNI.
+    public String mModelFile;
+    public String mParamsFile;
+    public String mLabelPath;
+    public RuntimeOption mRuntimeOption;
+    public boolean mInitialized = false;
+
+    public Recognizer() {
+        mModelFile = "";
+        mParamsFile = "";
+        mLabelPath = "";
+        mRuntimeOption = new RuntimeOption();
+        mInitialized = false;
+    }
+
+    public Recognizer(String modelFile,
+                      String paramsFile,
+                      String labelPath) {
+        mModelFile = modelFile;
+        mParamsFile = paramsFile;
+        mLabelPath = labelPath;
+        mRuntimeOption = new RuntimeOption();
+        mInitialized = true;
+    }
+
+    public Recognizer(String modelFile,
+                      String paramsFile,
+                      String labelPath,
+                      RuntimeOption option) {
+        mModelFile = modelFile;
+        mParamsFile = paramsFile;
+        mLabelPath = labelPath;
+        mRuntimeOption = option;
+        mInitialized = true;
+    }
+
+    public boolean initialized() {
+        return mInitialized;
+    }
+}