CamCard like app to recognize text from image and fill in form

Question

I want to create a CamCard like app which will work as ocr and fill text into specific fields, I have used Firebase MLKit for text recognizer from image but the issue is it gives me text as list now how to get which text is related to which field my basic implementation is as under

 FirebaseApp.initializeApp(this);
        FirebaseVisionImage image = FirebaseVisionImage.fromBitmap(bm);



FirebaseVisionTextRecognizer textRecognizer = FirebaseVision.getInstance()
                .getOnDeviceTextRecognizer();
        textRecognizer.processImage(image)
                .addOnSuccessListener(new OnSuccessListener<FirebaseVisionText>() {
                    @Override
                    public void onSuccess(FirebaseVisionText result) {
                        // Task completed successfully
                        // ...
                        String resultText = result.getText();
                        for (FirebaseVisionText.TextBlock block : result.getTextBlocks()) {
                            String blockText = block.getText();
                            Float blockConfidence = block.getConfidence();
                            List<RecognizedLanguage> blockLanguages = block.getRecognizedLanguages();
                            Point[] blockCornerPoints = block.getCornerPoints();
                            Rect blockFrame = block.getBoundingBox();
                            for (FirebaseVisionText.Line line : block.getLines()) {
                                String lineText = line.getText();
                                Float lineConfidence = line.getConfidence();
                                List<RecognizedLanguage> lineLanguages = line.getRecognizedLanguages();
                                Point[] lineCornerPoints = line.getCornerPoints();
                                Rect lineFrame = line.getBoundingBox();
                                for (FirebaseVisionText.Element element : line.getElements()) {
                                    String elementText = element.getText();
                                    Float elementConfidence = element.getConfidence();
                                    List<RecognizedLanguage> elementLanguages = element.getRecognizedLanguages();
                                    Point[] elementCornerPoints = element.getCornerPoints();
                                    Rect elementFrame = element.getBoundingBox();
                                }
                            }
                        }
                    }
                })
                .addOnFailureListener(
                        new OnFailureListener() {
                            @Override
                            public void onFailure(@NonNull Exception e) {
                                // Task failed with an exception
                                // ...
                            }
                        });

From the above listener i will get list of all the texts, Kindly demonstrate how to set text to their appropriate fields

Answer 1

private void runTextRecognition()
{

    // mSelectedImage <- Bitmap ( picture to find text )

    // convert bitmap in FirebaseVisionImage
    FirebaseVisionImage image = FirebaseVisionImage.fromBitmap(mSelectedImage);
    FirebaseVisionTextRecognizer textRecognizer = FirebaseVision.getInstance()
            .getOnDeviceTextRecognizer();

    // disable btn search text in activity.
    button_search_text.setEnabled(false);

    textRecognizer.processImage(image)
            .addOnSuccessListener(new OnSuccessListener<FirebaseVisionText>() {
                @Override
                public void onSuccess(FirebaseVisionText result)
                {
                    // send FirebaseVisionText ( txt ) 
                    processTextRecognitionResult(result);
                }
            })
            .addOnFailureListener(
                    new OnFailureListener() {
                        @Override
                        public void onFailure(@NonNull Exception e)
                        {
                            button_search_text.setEnabled(true);
                            e.printStackTrace();
                        }
                    });
}

// processTextRecognitionResult -> parse the results 
private void processTextRecognitionResult(FirebaseVisionText texts)
{
    List<FirebaseVisionText.TextBlock> blocks = texts.getTextBlocks();

    // ERROR -> No text found
    if (blocks.size() == 0) {
        txt_descripcion.setText( getResources().getString( R.string.alert_no_text ) );
        return;
    }
    mGraphicOverlay.clear();
    for (int i = 0; i < blocks.size(); i++) {
        List<FirebaseVisionText.Line> lines = blocks.get(i).getLines();
        for (int j = 0; j < lines.size(); j++) {
            List<FirebaseVisionText.Element> elements = lines.get(j).getElements();
            for (int k = 0; k < elements.size(); k++) 
            {
                //display result in picture
                Graphic textGraphic = new TextGraphic(mGraphicOverlay, elements.get(k));
                mGraphicOverlay.add(textGraphic);

                // (string) To get text you can use -> elements.get(k).getText() 
                Log.d(TAG, elements.get(k).getText() );

            }
        }
    }

}

Example [ Full explanation ] [ Step 6 ]
https://codelabs.developers.google.com/codelabs/mlkit-android/#5

Example [ Full Code ]
https://github.com/googlecodelabs/mlkit-android/blob/6da8e85b92ca85c60e1c15f74dd6a8fefb22836f/final/app/src/main/java/com/google/firebase/codelab/mlkit/MainActivity.java#L205

Docs
https://firebase.google.com/docs/ml-kit/android/recognize-text#2-extract-text-from-blocks-of-recognized-text