android ocr 图像识别 实例源码

【核心代码】

package com.example.ocr;

import java.io.File;
import android.app.Activity;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import android.provider.MediaStore;

public class MainActivity extends Activity {

	private static final String tag="MainActivity";
	private int CHOOSE_IMAGE = 1;
	private int CHOOSE_CAMERA = 2;
	private String imageFilePath = ""; 
	private boolean keyBack;
	private Button btnGetpic = null;
	private Button btnCamera = null;
	private Button btnRecognition = null;
	private ImageView imageView = null;
	private TextView textView = null;
	private Bitmap oriPicture = null;
	//private Bitmap finPicture = null;
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		mainInitialize();
	}
	
	
	public void mainInitialize(){
		
		btnCamera = (Button) findViewById(R.id.getCam);
		btnGetpic = (Button) findViewById(R.id.getPic);
		keyBack = false;
		Log.i(tag, "initiate successfully");
		
		btnGetpic.setOnClickListener(new OnClickListener() {
			public void onClick(View v) {
				//select a particular kind of data and return it
				Intent intent = new Intent(Intent.ACTION_GET_CONTENT);  
				intent.setType("image/*"); //sending image
				startActivityForResult(intent,CHOOSE_IMAGE);
			}
		});

		btnCamera.setOnClickListener(new OnClickListener() {
			public void onClick(View v) {
				
				long dataTake = System.currentTimeMillis();
				imageFilePath = Environment.getExternalStorageDirectory().getAbsolutePath()     
		                "/tesseract/"   dataTake   ".jpg";       //save directory
		        File imageFile = new File(imageFilePath); 
		        Uri imageFileUri = Uri.fromFile(imageFile); 
				//have the camera application capture an image and return it
				Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);  
				intent.putExtra(MediaStore.EXTRA_OUTPUT, imageFileUri);  
				//Launch the camera application for the result when it finished
				startActivityForResult(intent,CHOOSE_CAMERA);
				Log.i(tag, "ready to skip");
			}
		});
	}
	
	
	@Override
	//Called when an activity you launched exits
	protected void onActivityResult(int requestCode, int resultCode, Intent data) {
		if (resultCode == RESULT_OK){
			
			setContentView(R.layout.show_image);
			btnRecognition = (Button) findViewById(R.id.getResult);
			textView = (TextView) findViewById(R.id.result);
			imageView = (ImageView) findViewById(R.id.showImage);
			textView.setVisibility(View.INVISIBLE);
			keyBack = true;
			Log.i(tag, "skip back successfully");
			
			if (requestCode == CHOOSE_IMAGE) {
				
				Uri uri = data.getData();
				String[] proj = { MediaStore.Images.Media.DATA };
				Cursor imagecursor = getContentResolver().query(uri,proj,null,null,null);
				int actual_image_column_index = imagecursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
				imagecursor.moveToFirst();
				String img_path = imagecursor.getString(actual_image_column_index);   //get the image path
				
				oriPicture = imageReceive(img_path);    //get the image and resize it if needed
				oriPicture = oriPicture.copy(Bitmap.Config.ARGB_8888, true);
				imageView.setImageBitmap(oriPicture); 
				Log.i(tag, "Ready to recognize image");

				btnRecognition.setOnClickListener(new OnClickListener() {
					public void onClick(View v) {
						textView.setText("text recognized(pic):\n" Tesseract.getText(oriPicture));   //get the String and show it
						textView.setVisibility(View.VISIBLE);
						imageView.setImageBitmap(oriPicture);
					}
				}); 
	            
			}
			
		  if(requestCode == CHOOSE_CAMERA) 
	      {
			  oriPicture = imageReceive(imageFilePath);  //get the image and resize it if needed
			  oriPicture = oriPicture.copy(Bitmap.Config.ARGB_8888, true);
			  imageView.setImageBitmap(oriPicture); 
			  Log.i(tag, "Ready to recognize image");
					
			  btnRecognition.setOnClickListener(new OnClickListener() {
				  public void onClick(View v) {
					  textView.setText("text recognized(cam):\n" Tesseract.getText(oriPicture));   //get the String and show it
					  textView.setVisibility(View.VISIBLE);
					  imageView.setImageBitmap(oriPicture);
				  }
			  });
	      }
		  
		  
		}
	}
	
	
	//get the image and resize it if it is too large for screen
		public Bitmap imageReceive(String image_path){
			Bitmap bmp = null;
			
			try{
				//get the screen size 
				DisplayMetrics dm = new DisplayMetrics();
				getWindowManager().getDefaultDisplay().getMetrics(dm);
				int dw = dm.widthPixels;
				int dh = dm.heightPixels;

				// Load up the image's dimensions not the image itself 
				BitmapFactory.Options bmpFactoryOptions = new BitmapFactory.Options();
				bmpFactoryOptions.inJustDecodeBounds = true;
				bmp = BitmapFactory.decodeFile(image_path,bmpFactoryOptions); 
				int heightRatio = (int)Math.ceil(bmpFactoryOptions.outHeight/(float)dh);
				int widthRatio = (int)Math.ceil(bmpFactoryOptions.outWidth/(float)dw);
				
				// If both of the ratios are greater than 1,  
		        // one of the sides of the image is greater than the screen 
				if (heightRatio > 1 && widthRatio > 1)
				{
					if (heightRatio > widthRatio) {
						// Height ratio is larger, scale according to it 
						bmpFactoryOptions.inSampleSize = heightRatio;  
					}
					else {
						// Width ratio is larger, scale according to it  
						bmpFactoryOptions.inSampleSize = widthRatio;
					}
				}
				bmpFactoryOptions.inJustDecodeBounds = false;   // Decode it for real  
				bmp = BitmapFactory.decodeFile(image_path,bmpFactoryOptions); 
				
				
			}
			catch(Exception e)
			{
				e.printStackTrace();
			}
			
			return bmp;
		}

		

		public boolean onKeyDown(int keyCode, KeyEvent event) {
			//Monitoring the return key
	        if (keyCode == KeyEvent.KEYCODE_BACK && event.getRepeatCount() == 0) {
	              if(keyBack){
	            	  setContentView(R.layout.activity_main);
	            	  mainInitialize();
	              }
	              else{
	            	  finish();
	            	  Log.i(tag, "app is over");
	              }
	              return true;
	          }
	          return super.onKeyDown(keyCode, event);
	      }
}