image processing

demo to get rectangles -->>.



  //1. Convert img1 into gray image
            Imgproc.cvtColor(img1, imageGray1, Imgproc.COLOR_RGB2GRAY);

            //2.blur the image ..ie smooth the image
            Imgproc.GaussianBlur(imageGray1, imgGaussianBlur, new Size(3, 3), 0);

            //3. edge detection
//            Imgproc.Sobel(imgGaussianBlur, imgSobel, -1, 1, 0);

            //4. Trhesholding the image
            Imgproc.adaptiveThreshold(imgGaussianBlur, imgAdaptiveThreshold, 255, Imgproc.ADAPTIVE_THRESH_GAUSSIAN_C, Imgproc.THRESH_BINARY_INV, 99, 4);
//
//            Imgproc.adaptiveThreshold(imageGray1, imgAdaptiveThreshold_forCrop, 255, CV_ADAPTIVE_THRESH_MEAN_C, CV_THRESH_BINARY, 99, 4);
//

            //Canny Edge Detection
            Imgproc.Canny(imgAdaptiveThreshold, imageCny1, 20, 40, 3, true);
            ///////////////////////////////////////////////////////////////////


            //////////////////Transform Canny to Bitmap/////////////////////////////////////////
            imgContours = imageCny1.clone();
//
            Imgproc.findContours(imgContours, contours, hierarchy, Imgproc.RETR_TREE, Imgproc.CHAIN_APPROX_SIMPLE);


            MatOfPoint2f[] contoursPoly = new MatOfPoint2f[contours.size()];
            Rect[] boundRect = new Rect[contours.size()];


            for (int i = 0; i < contours.size(); i++) {
                contoursPoly[i] = new MatOfPoint2f();
                Imgproc.approxPolyDP(new MatOfPoint2f(contours.get(i).toArray()), contoursPoly[i], 3, true);
                boundRect[i] = Imgproc.boundingRect(new MatOfPoint(contoursPoly[i].toArray()));
            }

            Mat drawing = img1.clone();
            Scalar color = new Scalar(255, 0, 0);
            for (int i = 0; i < contours.size(); i++) {

//                if (checkImageRatio(boundRect[i])) {

                if (basicChecks(boundRect[i])) {
                    Imgproc.rectangle(drawing, boundRect[i].tl(), boundRect[i].br(), color, 2);

                    if (checkIntensity(drawing)) {
                        imgDetectedPlateTrue = drawing.clone();
                    }
                }

//                }

            }