Desktop : OpenCV Denoise 

<h5>Goal</h5>
Test OpenCV denoise.

```OpenCV_Denoise_TVL1.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;
import java.util.ArrayList;
import java.util.List;

public class OpenCV_Denoise_TVL1 {
    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_Denoise_TVL1 window = new OpenCV_Denoise_TVL1();
                    window.frmjavaSwing.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }
    /**
     * Create the application.
     */
    public OpenCV_Denoise_TVL1() {
        initialize();

    }

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

        BufferedImage image=matToBufferedImage(source);

        frmjavaSwing = new JFrame();
        frmjavaSwing.setTitle("opencv denoise_TVL1處理練習");
        frmjavaSwing.setBounds(100, 100, 520, 550);
        frmjavaSwing.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frmjavaSwing.getContentPane().setLayout(null);

        final JLabel showLambdaValue = new JLabel("0");
        showLambdaValue.setBounds(267, 10, 46, 15);
        frmjavaSwing.getContentPane().add(showLambdaValue);

        final JLabel showNitersValue = new JLabel("1");
        showNitersValue.setBounds(456, 10, 46, 15);
        frmjavaSwing.getContentPane().add(showNitersValue);

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

        final JSlider slider_niters = new JSlider();
        slider_niters.setMinimum(1);
        slider_niters.setValue(1);
        slider_niters.setMaximum(20);
        slider_niters.setBounds(371, 10, 75, 25);
        frmjavaSwing.getContentPane().add(slider_niters);

        final JSlider slider_lambda = new JSlider();
        slider_lambda.setMinimum(1);
        slider_lambda.setMaximum(50);
        slider_lambda.setValue(1);
        slider_lambda.addChangeListener(new ChangeListener() {
            public void stateChanged(ChangeEvent arg0) {
                //System.out.println(slider_alpha.getValue());
                showLambdaValue.setText(slider_lambda.getValue()+"");
                BufferedImage newImage=matToBufferedImage(Denoise(source,slider_lambda.getValue(),slider_niters.getValue()));
                lblNewLabel.setIcon(new ImageIcon(newImage));
            }
        });
        slider_lambda.setBounds(66, 10, 200, 25);
        frmjavaSwing.getContentPane().add(slider_lambda);

        JLabel lblAlpha = new JLabel("lambda");
        lblAlpha.setBounds(10, 20, 46, 15);
        frmjavaSwing.getContentPane().add(lblAlpha);

        JLabel lblBeta = new JLabel("niters");
        lblBeta.setBounds(323, 10, 46, 15);
        frmjavaSwing.getContentPane().add(lblBeta);


        slider_niters.addChangeListener(new ChangeListener() {
            public void stateChanged(ChangeEvent arg0) {
                showNitersValue.setText(slider_niters.getValue()+"");
                BufferedImage newImage=matToBufferedImage(Denoise(source,slider_lambda.getValue(),slider_niters.getValue()));
                lblNewLabel.setIcon(new ImageIcon(newImage));
            }
        });
    }
    public Mat Denoise(Mat source,int lambda,int niters){
        Mat im = Imgcodecs.imread("D:\\projects\\Java\\OpenCV_Samples\\resource\\imgs\\lena.jpg",Imgcodecs.CV_LOAD_IMAGE_GRAYSCALE);
        Mat im1 = Imgcodecs.imread("D:\\projects\\Java\\OpenCV_Samples\\resource\\imgs\\lena1.jpg",Imgcodecs.CV_LOAD_IMAGE_GRAYSCALE);
        Mat im2 = Imgcodecs.imread("D:\\projects\\Java\\OpenCV_Samples\\resource\\imgs\\lena2.jpg", Imgcodecs.CV_LOAD_IMAGE_GRAYSCALE);
        List<Mat> srcList=new ArrayList<Mat>();
        srcList.add(im);
//		srcList.add(im1);
//		srcList.add(im2);
        Mat destination=new Mat(source.rows(),source.cols(),source.type());
        Photo.denoise_TVL1(srcList, destination,lambda,niters);
        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>
![denoise_tvl1.JPG](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/276243/770ca802-d476-5509-e3e2-e9abd6e5eebd.jpeg)