I am a student and a beginner at android development and is required to do an android OCR function for a Contact Management Application for my school project.This is for transforming the image into text from name cards.
I have searched many forums for information regarding this and found several good examples of such.
Currently I have found an open source code online that does not require set up of ndk and environment variables etc in order to set up. However when i implemented it into eclipse(juno), there is a minor error in which i am unsure of how to resolve.
I have googled quite a while without any results. Therefore, deciding to ask here. Below are the codes with error.
final class OcrRecognizeAsyncTask extends AsyncTask<Void, Void, Boolean> {
// private static final boolean PERFORM_FISHER_THRESHOLDING = false;
// private static final boolean PERFORM_OTSU_THRESHOLDING = false;
// private static final boolean PERFORM_SOBEL_THRESHOLDING = false;
private CaptureActivity activity;
private TessBaseAPI baseApi;
private byte[] data;
private int width;
private int height;
private OcrResult ocrResult;
private long timeRequired;
OcrRecognizeAsyncTask(CaptureActivity activity, TessBaseAPI baseApi, byte[] data, int width, int height) {
this.activity = activity;
this.baseApi = baseApi;
this.data = data;
this.width = width;
this.height = height;
}
@Override
protected Boolean doInBackground(Void... arg0) {
long start = System.currentTimeMillis();
Bitmap bitmap = activity.getCameraManager().buildLuminanceSource(data, width, height).renderCroppedGreyscaleBitmap();
String textResult;
// if (PERFORM_FISHER_THRESHOLDING) {
// Pix thresholdedImage = Thresholder.fisherAdaptiveThreshold(ReadFile.readBitmap(bitmap), 48, 48, 0.1F, 2.5F);
// Log.e("OcrRecognizeAsyncTask", "thresholding completed. converting to bmp. size:" + bitmap.getWidth() + "x" + bitmap.getHeight());
// bitmap = WriteFile.writeBitmap(thresholdedImage);
// }
// if (PERFORM_OTSU_THRESHOLDING) {
// Pix thresholdedImage = Binarize.otsuAdaptiveThreshold(ReadFile.readBitmap(bitmap), 48, 48, 9, 9, 0.1F);
// Log.e("OcrRecognizeAsyncTask", "thresholding completed. converting to bmp. size:" + bitmap.getWidth() + "x" + bitmap.getHeight());
// bitmap = WriteFile.writeBitmap(thresholdedImage);
// }
// if (PERFORM_SOBEL_THRESHOLDING) {
// Pix thresholdedImage = Thresholder.sobelEdgeThreshold(ReadFile.readBitmap(bitmap), 64);
// Log.e("OcrRecognizeAsyncTask", "thresholding completed. converting to bmp. size:" + bitmap.getWidth() + "x" + bitmap.getHeight());
// bitmap = WriteFile.writeBitmap(thresholdedImage);
// }
try {
baseApi.setImage(ReadFile.readBitmap(bitmap));
textResult = baseApi.getUTF8Text();
timeRequired = System.currentTimeMillis() - start;
// Check for failure to recognize text
if (textResult == null || textResult.equals("")) {
return false;
}
ocrResult = new OcrResult();
ocrResult.setWordConfidences(baseApi.wordConfidences());
ocrResult.setMeanConfidence( baseApi.meanConfidence());
ocrResult.setRegionBoundingBoxes(baseApi.getRegions().getBoxRects());
ocrResult.setTextlineBoundingBoxes(baseApi.getTextlines().getBoxRects());
ocrResult.setWordBoundingBoxes(baseApi.getWords().getBoxRects());
ocrResult.setStripBoundingBoxes(baseApi.getStrips().getBoxRects());
// Iterate through the results.
final ResultIterator iterator = baseApi.getResultIterator();
int[] lastBoundingBox;
ArrayList<Rect> charBoxes = new ArrayList<Rect>();
iterator.begin();
do {
lastBoundingBox =iterator.getBoundingBox(PageIteratorLevel.RIL_SYMBOL);
Rect lastRectBox = new Rect(lastBoundingBox[0], lastBoundingBox[1],
lastBoundingBox[2], lastBoundingBox[3]);
charBoxes.add(lastRectBox);
} while (iterator.next(PageIteratorLevel.RIL_SYMBOL));
iterator.delete();
ocrResult.setCharacterBoundingBoxes(charBoxes);
} catch (RuntimeException e) {
Log.e("OcrRecognizeAsyncTask", "Caught RuntimeException in request to Tesseract. Setting state to CONTINUOUS_STOPPED.");
e.printStackTrace();
try {
baseApi.clear();
activity.stopHandler();
} catch (NullPointerException e1) {
// Continue
}
return false;
}
timeRequired = System.currentTimeMillis() - start;
ocrResult.setBitmap(bitmap);
ocrResult.setText(textResult);
ocrResult.setRecognitionTimeRequired(timeRequired);
return true;
}
@Override
protected void onPostExecute(Boolean result) {
super.onPostExecute(result);
Handler handler = activity.getHandler();
if (handler != null) {
// Send results for single-shot mode recognition.
if (result) {
Message message = Message.obtain(handler, R.id.ocr_decode_succeeded, ocrResult);
message.sendToTarget();
} else {
Message message = Message.obtain(handler, R.id.ocr_decode_failed, ocrResult);
message.sendToTarget();
}
activity.getProgressDialog().dismiss();
}
if (baseApi != null) {
baseApi.clear();
}
}
}
The error resides in the do and while loop:
do {
lastBoundingBox = iterator.***getBoundingBox***(PageIteratorLevel.RIL_SYMBOL);
Rect lastRectBox = new Rect(lastBoundingBox[0], lastBoundingBox[1],
lastBoundingBox[2], lastBoundingBox[3]);
charBoxes.add(lastRectBox);
} while (iterator.next(PageIteratorLevel.RIL_SYMBOL));
iterator.***delete***();
ocrResult.setCharacterBoundingBoxes(charBoxes);
In the above codes as bolded, getBoundingBox and delete has the following error:
"The method getBoundingBox(int) is undefined for the type ResultIterator"
"The method getBoundingBox(int) is undefined for the type ResultIterator"
I have tried several methods but just cannot make it work out. If there are any solutions to this please help me out, thank you very much.
@SebastianRoth is right: The pre-compiled library you're using is out of date. I suggest installing the NDK and following the build instructions for the OCR engine. That will recompile the library, including its getBoundingBox method.