Question

我正在使用OpenCV，Tesseract和Java制作车牌识别软件，但遇到问题，我似乎无法正确分割我的文字，并不总是我得到所有字符都被检测到并且用边框限制这些是我的一些输出与我的代码...当我检测到字符时，我从来不知道哪个字符在哪个框中，所以当我通过tesseract传递它们时，它们会混乱，我如何格式化我的字符串？

尽管有明显可见的字符，但这个失败了：

即使6清晰可见，也无法检测到Z和6：

以下是我的代码：

originalFrame = image.clone();
    roiColor = image.clone();
    Imgproc.cvtColor(image, image, Imgproc.COLOR_BGR2GRAY, 0);
    originalFrameGrayScale = image.clone();
    Mat morph = Imgproc.getStructuringElement(Imgproc.MORPH_RECT, new Size(9, 9));
    Imgproc.morphologyEx(image, image, Imgproc.MORPH_TOPHAT, morph);
    Imgproc.Sobel(image, image, -1, 2, 0);
    Imgproc.GaussianBlur(image, image, new Size(5,5), 3,3);
    Imgproc.morphologyEx(image, image, Imgproc.MORPH_CLOSE, morph);
    Imgproc.threshold(image, image, 200, 255, Imgproc.THRESH_OTSU);
    Vector<Rect> rectangles = detectionContour(image);
    Mat roi = originalFrameGrayScale.clone();
    if(!rectangles.isEmpty()){
    roi = originalFrameGrayScale.submat(rectangles.get(0));
    roiBlack = roi.clone();
    roiColor = roiColor.submat(rectangles.get(0));
    Imgproc.rectangle(originalFrame, rectangles.get(0).br(),    rectangles.get(0).tl(), new Scalar(0,0,255), 2);
   }

    Imgproc.medianBlur(roi, roi, 3); 
   Imgproc.adaptiveThreshold(roi, roi, 225, Imgproc.ADAPTIVE_THRESH_GAUSSIAN_C, Imgproc.THRESH_BINARY, 15, 3);
   roiBinarize = roi.clone();
   Mat erode = Imgproc.getStructuringElement(Imgproc.MORPH_RECT, new Size(1, 1));
   Mat dilate = Imgproc.getStructuringElement(Imgproc.MORPH_RECT,new Size(1, 1));
   Imgproc.morphologyEx(roi, roi, Imgproc.MORPH_OPEN, dilate);
   Imgproc.morphologyEx(roi, roi, Imgproc.MORPH_OPEN, erode);
   Imgproc.Canny(roi, roi, 150, 150 * 3, 3, true);
   Vector<Rect> letters = detectionPlateCharacterContour(roi);
   doTesseractOCR(letters, roiBinarize);

    private static void doTesseractOCR(Vector<Rect> letters, Mat plate){
    Tesseract instance = new Tesseract(); //
    instance.setLanguage(LANGUAGE);
    String resultPlate = "";
    for(int i= 0; i < letters.size(); i++){

     BufferedImage letter = OpenCvUtils.Mat2bufferedImage(plate.submat(letters.get(i)));
        try {
        String result = instance.doOCR(letter);
        resultPlate += result + " position "+i;

        } catch (TesseractException e) {
        System.err.println(e.getMessage());
        }
        System.out.println("Tesseract output: "+resultPlate);
    }
}



    private static Vector<Rect> detectionPlateCharacterContour(Mat roi) {
    Mat contHierarchy = new Mat();
    Mat imageMat = roi.clone();
    Rect rect = null;
    List<MatOfPoint> contours = new ArrayList<>();
    Imgproc.findContours(imageMat, contours, contHierarchy, Imgproc.RETR_EXTERNAL, Imgproc.CHAIN_APPROX_NONE);
    Vector<Rect> rect_array = new Vector<>();

    for (int i = 0; i < contours.size(); i++) {
        rect = Imgproc.boundingRect(contours.get(i));
        double ratio = 0;

               if(rect.height > rect.width){
            ratio = rect.height/rect.width;

            }else{
                ratio = rect.width/rect.height;

            }
         Logger.printMessage("Ratio of letter: "+ratio);
      double contourarea = Imgproc.contourArea(contours.get(i));
         if (contourarea >= 100 && contourarea <= 1000 && ( ratio >= 1 && ratio <= 2)) {
         Imgproc.rectangle(roiColor, rect.br(), rect.tl(), new Scalar(255,0,0));
           rect_array.add(rect);
         }
    }


    contHierarchy.release();
    return rect_array;
}

OpenCV Java文本分段

0 个答案: