Tesseract4Android 安卓ocr添加打开相册识别

MainFragment.java

package cz.adaptech.tesseract4android.sample.ui.main;

import android.app.Activity;
import android.content.ClipData;
import android.content.ClipboardManager;
import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Bundle;
import android.provider.MediaStore;
import android.text.method.ScrollingMovementMethod;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
import androidx.lifecycle.ViewModelProvider;
import java.io.File;
import java.io.FileOutputStream;

import cz.adaptech.tesseract4android.sample.Assets;
import cz.adaptech.tesseract4android.sample.Config;
import cz.adaptech.tesseract4android.sample.databinding.FragmentMainBinding;
import com.googlecode.tesseract.android.TessBaseAPI;

public class MainFragment extends Fragment {

    private static final int PICK_IMAGE = 1; // 打开相册的请求码
    private FragmentMainBinding binding;
    private MainViewModel viewModel;
    private TessBaseAPI tessBaseAPI;

    public static MainFragment newInstance() {
        return new MainFragment();
    }

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        viewModel = new ViewModelProvider(this).get(MainViewModel.class);

        // Copy sample image and language data to storage
        Assets.extractAssets(requireContext());
        if (!viewModel.isInitialized()) {
            String dataPath = Assets.getTessDataPath(requireContext());
            viewModel.initTesseract(dataPath, Config.TESS_LANG, Config.TESS_ENGINE);
        }

        // Initialize Tesseract
        tessBaseAPI = new TessBaseAPI();
        String dataPath = Assets.getTessDataPath(requireContext());
        tessBaseAPI.init(dataPath, Config.TESS_LANG);
    }

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container,
                             @Nullable Bundle savedInstanceState) {
        binding = FragmentMainBinding.inflate(inflater, container, false);
        return binding.getRoot();
    }

    @Override
    public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);

        binding.image.setImageBitmap(Assets.getImageBitmap(requireContext()));

        // 选择图片按钮点击事件
        assert binding.openGalleryButton != null;
        binding.openGalleryButton.setOnClickListener(v -> {
            Intent intent = new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
            startActivityForResult(intent, PICK_IMAGE);
        });

        binding.start.setOnClickListener(v -> {
            // 开始识别，之前需要设置好图片
            Bitmap bitmap = Assets.getImageBitmap(requireContext());

            assert bitmap != null;
            viewModel.recognizeImage(bitmap);

            //OCR 识别操作放入新的线程中以防止 UI 卡顿
            new Thread(() -> {
                tessBaseAPI.setImage(bitmap);
                String recognizedText = tessBaseAPI.getUTF8Text(); // 执行OCR识别

                requireActivity().runOnUiThread(() -> binding.text.setText(recognizedText)); // 显示识别结果
            }).start();
        });

        binding.stop.setOnClickListener(v -> {
            tessBaseAPI.stop(); // 停止识别
            viewModel.stop();
        });

        assert binding.copyButton != null;
        binding.copyButton.setOnClickListener(v -> copyToClipboard(binding.text.getText().toString())); // 复制文本
        assert binding.shareButton != null;
        binding.shareButton.setOnClickListener(v -> shareText(binding.text.getText().toString())); // 分享文本
        binding.text.setMovementMethod(new ScrollingMovementMethod());

        // 观察处理状态
        viewModel.getProcessing().observe(getViewLifecycleOwner(), processing -> {
            binding.start.setEnabled(!processing);
            binding.stop.setEnabled(processing);
        });
        viewModel.getProgress().observe(getViewLifecycleOwner(), progress -> {
            binding.status.setText(progress);
        });
        viewModel.getResult().observe(getViewLifecycleOwner(), result -> {
            binding.text.setText(result);
        });
    }

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if (requestCode == PICK_IMAGE && resultCode == Activity.RESULT_OK && data != null) {
            Uri selectedImageUri = data.getData();
            Bitmap bitmap;

            try {
                // 使用异步任务或线程来加载和处理图像
                bitmap = MediaStore.Images.Media.getBitmap(requireActivity().getContentResolver(), selectedImageUri);
                // 缩放图像以减少内存使用，例如每次只加载部分
                bitmap = Bitmap.createScaledBitmap(bitmap, bitmap.getWidth() / 2, bitmap.getHeight() / 2, true);
                binding.image.setImageBitmap(bitmap); // 设置选中的图片到ImageView

                // 将选中的bitmap保存为文件（如果需要）
                File imageFile = Assets.getImageFile(requireContext());
                FileOutputStream fos = new FileOutputStream(imageFile);
                bitmap.compress(Bitmap.CompressFormat.PNG, 100, fos);
                fos.flush();
                fos.close();

                // 设置Tesseract的输入图像
                tessBaseAPI.setImage(bitmap);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        if (tessBaseAPI != null) {
            tessBaseAPI.recycle(); // 释放资源
        }
    }

    // 复制到剪贴板的方法
    private void copyToClipboard(String text) {
        ClipboardManager clipboard = (ClipboardManager) requireContext().getSystemService(Context.CLIPBOARD_SERVICE);
        ClipData clip = ClipData.newPlainText("OCR Result", text);
        clipboard.setPrimaryClip(clip);
        Toast.makeText(requireContext(), "文本已复制到剪贴板", Toast.LENGTH_SHORT).show();
    }

    // 分享文本的方法
    private void shareText(String text) {
        Intent sendIntent = new Intent();
        sendIntent.setAction(Intent.ACTION_SEND);
        sendIntent.putExtra(Intent.EXTRA_TEXT, text);
        sendIntent.setType("text/plain");
        startActivity(Intent.createChooser(sendIntent, "分享文本"));
    }
}

xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".ui.main.MainFragment">

    <ImageView
        android:id="@+id/image"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1" />

    <TextView
        android:id="@+id/status"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:textAlignment="center"
        android:textStyle="bold"
        tools:text="Status" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:orientation="horizontal">

        <Button
            android:id="@+id/start"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Start" />

        <Button
            android:id="@+id/stop"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Stop" />
    </LinearLayout>

    <!-- 添加打开相册按钮 -->
    <Button
        android:id="@+id/openGalleryButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:text="打开相册" />

    <TextView
        android:id="@+id/text"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        android:padding="16dp"
        android:scrollbars="vertical"
        android:text="" />
    <!-- 新增的复制按钮 -->
    <Button
        android:id="@+id/copyButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="复制文本"
        android:layout_gravity="center" />

    <!-- 新增的分享按钮 -->
    <Button
        android:id="@+id/shareButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="分享文本"
        android:layout_gravity="center" />
</LinearLayout>

参考github
adaptech-czTesseract4Android