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How to use Tesseract library for OCR.
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| 1. Download the tesseract library from the following link named libs.zip. | |
| https://www.dropbox.com/s/9fwqz88sck3xlk4/libs.zip?dl=0 | |
| 2. Extract the zip folder. | |
| * If you are using Eclipse then copy all the files and folders from libs folder to libs folder in your project. | |
| * if you are using Android Studio then Copy all th e folders from libs folder to src/main/jniLibs folder in your project and copy the classes.jar to libs folder. | |
| 3. Add image containing text inside your downloads folder and give the name a.png. | |
| 4. create folder named tessdata inside the assets folder in your project. | |
| 5. download the file named eng.traineddata from the below link and copy it inside the tessdata folder created in the 4th step. | |
| https://www.dropbox.com/s/7xdnfzp8qsy4ll9/eng.traineddata?dl=0 | |
| 6. add permission to manifest "android.permission.WRITE_EXTERNAL_STORAGE" | |
| 7. copy and paste the below code. | |
| try{ | |
| bitmap = BitmapFactory.decodeFile(Environment.getExternalStorageDirectory().getAbsolutePath()+"/download/a.png"); | |
| // _path = path to the image to be OCRed | |
| ExifInterface exif = new ExifInterface(Environment.getExternalStorageDirectory().getAbsolutePath()+"/download/a.png"); | |
| int exifOrientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL); | |
| int rotate = 0; | |
| switch (exifOrientation) { | |
| case ExifInterface.ORIENTATION_ROTATE_90: | |
| rotate = 90; | |
| break; | |
| case ExifInterface.ORIENTATION_ROTATE_180: | |
| rotate = 180; | |
| break; | |
| case ExifInterface.ORIENTATION_ROTATE_270: | |
| rotate = 270; | |
| break; | |
| } | |
| if (rotate != 0) { | |
| int w = bitmap.getWidth(); | |
| int h = bitmap.getHeight(); | |
| // Setting pre rotate | |
| Matrix mtx = new Matrix(); | |
| mtx.preRotate(rotate); | |
| // Rotating Bitmap & convert to ARGB_8888, required by tess | |
| bitmap = Bitmap.createBitmap(bitmap, 0, 0, w, h, mtx, false); | |
| } | |
| bitmap = bitmap.copy(Bitmap.Config.ARGB_8888, true); | |
| TessBaseAPI baseApi = new TessBaseAPI(); | |
| // tesseract reads language from tesseract folder, create it if not exists. | |
| File f = new File(Environment.getExternalStorageDirectory().getAbsolutePath()+"/tesseract/tessdata"); | |
| if(!f.exists()){ | |
| f.mkdirs(); | |
| } | |
| // copy the eng lang file from assets folder if not exists. | |
| File f1 = new File(Environment.getExternalStorageDirectory().getAbsolutePath()+"/tesseract/tessdata/eng.traineddata"); | |
| if(!f1.exists()){ | |
| InputStream in = getAssets().open("tessdata/eng.traineddata"); | |
| FileOutputStream fout = new FileOutputStream(f1); | |
| byte[] buf = new byte[1024]; | |
| int len; | |
| while ((len = in.read(buf)) > 0) { | |
| fout.write(buf, 0, len); | |
| } | |
| in.close(); | |
| fout.close(); | |
| } | |
| // DATA_PATH = Path to the storage and data path must contain tessdata subdirectory | |
| // lang = for which the language data exists, usually "eng" | |
| // Eg. baseApi.init("/mnt/sdcard/tesseract/tessdata/eng.traineddata", "eng"); | |
| baseApi.init(Environment.getExternalStorageDirectory().getAbsolutePath()+"/tesseract", "eng"); | |
| baseApi.setImage(bitmap); | |
| String recognizedText = baseApi.getUTF8Text(); | |
| baseApi.end(); | |
| Toast.makeText(getApplicationContext(), recognizedText, Toast.LENGTH_LONG).show(); | |
| System.out.println("Text is>>>>>>>>>>>>>>>>>" + recognizedText); | |
| }catch(Exception e){ | |
| e.printStackTrace(); | |
| } |
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Got so much easy way to use OCR...thanx buddy..