logic.helpclass.Util.java Source code

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Here is the source code for logic.helpclass.Util.java

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package logic.helpclass;

import org.opencv.core.Core;
import static org.opencv.core.CvType.CV_32FC1;
import org.opencv.core.Mat;
import org.opencv.core.Point;
import org.opencv.core.Rect;
import org.opencv.core.Scalar;
import org.opencv.imgproc.Imgproc;

/**
 * Some small functions, solved small tasks, such as: conver image to gray scale, 
 * equalize image histogram, calculate rotation matrix, etc.
 * @author Igor Dumchykov
 */
public class Util {

    /**
    * Convert color and equalize histogram
    * @param frame - clor frame   
    * @return grayMat - gray-scaled frame
    */
    static public Mat preprocessFrame(Mat frame) {
        Mat grayMat = new Mat();

        //Preprocessing
        Imgproc.cvtColor(frame, grayMat, Imgproc.COLOR_RGBA2GRAY);
        Imgproc.equalizeHist(grayMat, grayMat);

        if (Parameters.IS_DEBUG)
            System.out.println("Frame was processed");

        return grayMat;
    }

    /**
     * Track template within the image
     * @param grayFrame
     * @param rect
     * @param temp
     * @return 
     */
    static public Rect trackTemplate(Mat grayFrame, Rect rect, Mat temp) {
        Rect searchRect = new Rect(new Point(rect.x - rect.width / 2, rect.y - rect.height / 2),
                new Point(rect.x + rect.width * 3 / 2, rect.y + rect.height * 3 / 2));

        Mat dst = new Mat(searchRect.width - temp.width() + 1, searchRect.height - temp.height() + 1, CV_32FC1);

        if ((searchRect.x < 0 || searchRect.y < 0) || (searchRect.x + searchRect.width > grayFrame.cols()
                || searchRect.y + searchRect.height > grayFrame.rows()))
            return null;

        Imgproc.matchTemplate(grayFrame.submat(searchRect), temp, dst, Imgproc.TM_SQDIFF_NORMED);

        Core.MinMaxLocResult result = Core.minMaxLoc(dst);

        //check new location: if coordinates change so variously, remain previous location
        if (true) {
            rect.x = (int) (searchRect.x + result.minLoc.x);
            rect.y = (int) (searchRect.y + result.minLoc.y);
            return rect;
        } else {
            return null;
        }
    }
}