Desktop : OpenCV Illumination Change

<H5>Result</H5>
Test OpenCV illumination change.

```OpenCV_IlluminationChange.java
import org.opencv.core.Core;
import org.opencv.core.Mat;
import org.opencv.imgcodecs.Imgcodecs;
import org.opencv.photo.Photo;

import javax.swing.*;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import java.awt.*;
import java.awt.image.BufferedImage;

public class OpenCV_IlluminationChange {
    static{ System.loadLibrary(Core.NATIVE_LIBRARY_NAME); }
    private JFrame frmjavaSwing;
    /**
     * Launch the application.
     */
    public static void main(String[] args) {

        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    OpenCV_IlluminationChange window = new OpenCV_IlluminationChange();
                    window.frmjavaSwing.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    /**
     * Create the application.
     */
    public OpenCV_IlluminationChange() {
        initialize();

    }

    /**
     * Initialize the contents of the frame.
     */
    private void initialize() {
        final Mat source = Imgcodecs.imread(
                "D:\\projects\\Java\\OpenCV_Samples\\resource\\imgs\\lena.jpg");

        BufferedImage image=matToBufferedImage(source);

        frmjavaSwing = new JFrame();
        frmjavaSwing.setTitle("opencv illuminationChange處理練習");
        frmjavaSwing.setBounds(100, 100, 520, 550);
        frmjavaSwing.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frmjavaSwing.getContentPane().setLayout(null);

        final JLabel showRedValue = new JLabel("1");
        showRedValue.setBounds(84, 32, 46, 15);
        frmjavaSwing.getContentPane().add(showRedValue);

        final JLabel showGreenValue = new JLabel("0.1");
        showGreenValue.setBounds(256, 32, 46, 15);
        frmjavaSwing.getContentPane().add(showGreenValue);

        final JLabel lblNewLabel = new JLabel("");
        lblNewLabel.setBounds(10, 68, 438, 438);
        lblNewLabel.setIcon(new ImageIcon(image));
        frmjavaSwing.getContentPane().add(lblNewLabel);

        final JSlider slider_beta = new JSlider();
        slider_beta.setValue(0);
        slider_beta.setMaximum(60);
        slider_beta.setBounds(220, 10, 75, 25);
        frmjavaSwing.getContentPane().add(slider_beta);

        final JSlider slider_alpha = new JSlider();
        slider_alpha.setMinimum(1);
        slider_alpha.setMaximum(600);
        slider_alpha.setValue(1);

        slider_alpha.setBounds(57, 10, 86, 25);
        frmjavaSwing.getContentPane().add(slider_alpha);

        JLabel lblAlpha = new JLabel("alpha");
        lblAlpha.setBounds(10, 10, 56, 15);
        frmjavaSwing.getContentPane().add(lblAlpha);

        JLabel lblBeta = new JLabel("beta");
        lblBeta.setBounds(155, 10, 67, 15);
        frmjavaSwing.getContentPane().add(lblBeta);
        slider_alpha.addChangeListener(new ChangeListener() {
            public void stateChanged(ChangeEvent arg0) {
                //System.out.println(slider_alpha.getValue());
                showRedValue.setText((float)slider_alpha.getValue()/10+"");
                BufferedImage newImage=matToBufferedImage(illuminationChange((float)slider_alpha.getValue()/10,(float)slider_beta.getValue()/10));
                lblNewLabel.setIcon(new ImageIcon(newImage));
            }
        });

        slider_beta.addChangeListener(new ChangeListener() {
            public void stateChanged(ChangeEvent arg0) {
                showGreenValue.setText((float)slider_beta.getValue()/10+"");
                BufferedImage newImage=matToBufferedImage(illuminationChange((float)slider_alpha.getValue()/10,(float)slider_beta.getValue()/10));
                lblNewLabel.setIcon(new ImageIcon(newImage));
            }
        });
    }
    public Mat illuminationChange(float alpha,float beta){
        Mat src = Imgcodecs.imread("D:\\projects\\Java\\OpenCV_Samples\\resource\\imgs\\lena.jpg",Imgcodecs.CV_LOAD_IMAGE_COLOR);
        Mat destination=new Mat();
        Mat src_mask = new Mat(src.rows(), src.cols(), src.depth());

        for (int i=0;i<src_mask.rows();i++){
            for (int j=0;j<src_mask.cols();j++){
                double[] data=new double[3];
                data=src_mask.get(i, j);
                data[0]= 255;
                src_mask.put(i, j, data);
            }
        }
        Photo.illuminationChange(src,src_mask,destination,alpha,beta);
        return destination;

    }

    public BufferedImage matToBufferedImage(Mat matrix) {
        int cols = matrix.cols();
        int rows = matrix.rows();
        int elemSize = (int)matrix.elemSize();
        byte[] data = new byte[cols * rows * elemSize];
        int type;
        matrix.get(0, 0, data);
        switch (matrix.channels()) {
            case 1:
                type = BufferedImage.TYPE_BYTE_GRAY;
                break;
            case 3:
                type = BufferedImage.TYPE_3BYTE_BGR;
                // bgr to rgb
                byte b;
                for(int i=0; i<data.length; i=i+3) {
                    b = data[i];
                    data[i] = data[i+2];
                    data[i+2] = b;
                }
                break;
            default:
                return null;
        }
        BufferedImage image2 = new BufferedImage(cols, rows, type);
        image2.getRaster().setDataElements(0, 0, cols, rows, data);
        return image2;
    }
}
```

<h5>Result</h5>
![opencv_illumination_change.JPG](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/276243/9e98af19-b064-cc1d-9c4f-98b772733a47.jpeg)