
Kita akan lanjutkan pembahasan OpenCV di Java dibagian sebelumnya yaitu menggunakan JFrame untuk menampilkan gambar serta diberikan feature untuk resize gambar. Editor yang kita gunakan berupa Netbeans agar mudah dalam drag and drop component SWING/AWT. Pembuatan aplikasi OpenCV di java sangat mudah koq, apalagi kalau menggunakan Netbeans.
Tampilan Aplikasi
Contents
Tampilan aplikasi OpenCV di Java untuk menampilkan gambar seperti berikut
Terdapat File Menu Buka untuk membuat gambar, serta slider untuk menentukan ratio resizenya, adapun component utamanya yaitu JScrollPane dan JLabel sebagai wadah untuk menampilkan gambar
Import Libary yang dibutuhkan
Oiya jangan lupa ya, kalian setting library OpenCV nya, baca sebelumnya. Berikut daftar import libary yang dibutuhkan
import org.opencv.core.Core; import org.opencv.core.Mat; import org.opencv.core.MatOfByte; import org.opencv.core.Size; import org.opencv.imgcodecs.Imgcodecs; import org.opencv.imgproc.Imgproc; import javax.imageio.ImageIO; import javax.swing.ImageIcon; import javax.swing.JFileChooser; import java.awt.image.BufferedImage; import java.io.ByteArrayInputStream; import java.io.IOException; import java.util.logging.Level; import java.util.logging.Logger; import java.io.File;
Variabel Global dan tambahan Kode pada method Constructor
Kita akan nambahkan variable global yaitu
Mat current ;
terus tambahkan kode berikut didalam method constructor untuk memastikan bahwa library OpenCV akan diload
System.loadLibrary(Core.NATIVE_LIBRARY_NAME);
Buat method untuk mengubah Mat ke BufferedImage
Untuk mempermudah pengubahan object class Mat ke BufferedImage, kita buatkan private methode yaitu
private BufferedImage Mat2BufferedImage(Mat matrix)throws Exception { MatOfByte mob=new MatOfByte(); Imgcodecs.imencode(".jpg", matrix, mob); byte ba[]=mob.toArray(); BufferedImage bi=ImageIO.read(new ByteArrayInputStream(ba)); return bi; }
Action Performed ketika Buka dipilih user
Tambahkan kode berikut ketika user memilih menu Buka
JFileChooser fileChooser = new JFileChooser(); fileChooser.setCurrentDirectory(new File(System.getProperty("user.home"))); int result = fileChooser.showOpenDialog(this); if (result == JFileChooser.APPROVE_OPTION) { File selectedFile = fileChooser.getSelectedFile(); System.out.println("Selected file: " + selectedFile.getAbsolutePath()); Imgcodecs imageCodecs = new Imgcodecs(); Mat matrix = Imgcodecs.imread(selectedFile.getAbsolutePath(),Imgcodecs.IMREAD_REDUCED_COLOR_2); current = matrix.clone(); try { this.jLabel1.setIcon(new ImageIcon(Mat2BufferedImage(matrix))); } catch (Exception ex) { Logger.getLogger(NewJFrame.class.getName()).log(Level.SEVERE, null, ex); } }
Action StateChanged ketika Slider digerakan
Berikut kode yang digunakan ketika slider sedang digeser
if (current==null) return; double ratio = this.jSlider1.getValue(); ratio /= 100; if (ratio==00) return; setTitle("Ukuran: "+ratio); int endl=0; Mat buff = new Mat(); Size scaleSize = new Size((int)(this.current.cols()*ratio), (int)(this.current.rows()*ratio)); Imgproc.resize(this.current,buff, scaleSize , 0, 0, Imgproc.INTER_AREA); BufferedImage buf; try { buf = Mat2BufferedImage(buff); this.jLabel1.setIcon(new ImageIcon(buf)); jLabel1.setHorizontalAlignment(javax.swing.SwingConstants.CENTER); } catch (Exception ex) { Logger.getLogger(NewJFrame.class.getName()).log(Level.SEVERE, null, ex); }
Kode lengkapnya bisa kalian pelajari di NewJFrame.java berikut ini
import org.opencv.core.Core; import org.opencv.core.Mat; import org.opencv.core.MatOfByte; import org.opencv.core.Size; import org.opencv.imgcodecs.Imgcodecs; import org.opencv.imgproc.Imgproc; import javax.imageio.ImageIO; import javax.swing.ImageIcon; import javax.swing.JFileChooser; import java.awt.image.BufferedImage; import java.io.ByteArrayInputStream; import java.io.IOException; import java.util.logging.Level; import java.util.logging.Logger; import java.io.File; /* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ /** * * @author bejo */ public class NewJFrame extends javax.swing.JFrame { Mat current ; /** * Creates new form NewJFrame */ public NewJFrame() throws IOException, Exception { initComponents(); System.loadLibrary(Core.NATIVE_LIBRARY_NAME); } /** * This method is called from within the constructor to initialize the form. * WARNING: Do NOT modify this code. The content of this method is always * regenerated by the Form Editor. */ @SuppressWarnings("unchecked") // <editor-fold defaultstate="collapsed" desc="Generated Code"> private void initComponents() { jScrollPane1 = new javax.swing.JScrollPane(); jLabel1 = new javax.swing.JLabel(); jSlider1 = new javax.swing.JSlider(); jMenuBar1 = new javax.swing.JMenuBar(); jMenu1 = new javax.swing.JMenu(); jMenuItem1 = new javax.swing.JMenuItem(); jMenu2 = new javax.swing.JMenu(); setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); jLabel1.setHorizontalAlignment(javax.swing.SwingConstants.CENTER); jScrollPane1.setViewportView(jLabel1); jSlider1.addChangeListener(new javax.swing.event.ChangeListener() { public void stateChanged(javax.swing.event.ChangeEvent evt) { jSlider1StateChanged(evt); } }); jMenu1.setText("File"); jMenuItem1.setText("Buka"); jMenuItem1.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { jMenuItem1ActionPerformed(evt); } }); jMenu1.add(jMenuItem1); jMenuBar1.add(jMenu1); jMenu2.setText("Edit"); jMenuBar1.add(jMenu2); setJMenuBar(jMenuBar1); javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane()); getContentPane().setLayout(layout); layout.setHorizontalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addGap(40, 40, 40) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false) .addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 539, Short.MAX_VALUE) .addComponent(jSlider1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)) .addContainerGap(40, Short.MAX_VALUE)) ); layout.setVerticalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addGap(29, 29, 29) .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 391, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED) .addComponent(jSlider1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE) .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)) ); pack(); }// </editor-fold> private void jSlider1StateChanged(javax.swing.event.ChangeEvent evt) { // TODO add your handling code here: if (current==null) return; double ratio = this.jSlider1.getValue(); ratio /= 100; if (ratio==00) return; setTitle("Ukuran: "+ratio); int endl=0; Mat buff = new Mat(); Size scaleSize = new Size((int)(this.current.cols()*ratio), (int)(this.current.rows()*ratio)); Imgproc.resize(this.current,buff, scaleSize , 0, 0, Imgproc.INTER_AREA); BufferedImage buf; try { buf = Mat2BufferedImage(buff); this.jLabel1.setIcon(new ImageIcon(buf)); jLabel1.setHorizontalAlignment(javax.swing.SwingConstants.CENTER); } catch (Exception ex) { Logger.getLogger(NewJFrame.class.getName()).log(Level.SEVERE, null, ex); } } private void jMenuItem1ActionPerformed(java.awt.event.ActionEvent evt) { // TODO add your handling code here: JFileChooser fileChooser = new JFileChooser(); fileChooser.setCurrentDirectory(new File(System.getProperty("user.home"))); int result = fileChooser.showOpenDialog(this); if (result == JFileChooser.APPROVE_OPTION) { File selectedFile = fileChooser.getSelectedFile(); System.out.println("Selected file: " + selectedFile.getAbsolutePath()); Imgcodecs imageCodecs = new Imgcodecs(); Mat matrix = Imgcodecs.imread(selectedFile.getAbsolutePath(),Imgcodecs.IMREAD_REDUCED_COLOR_2); current = matrix.clone(); try { this.jLabel1.setIcon(new ImageIcon(Mat2BufferedImage(matrix))); } catch (Exception ex) { Logger.getLogger(NewJFrame.class.getName()).log(Level.SEVERE, null, ex); } } } private BufferedImage Mat2BufferedImage(Mat matrix)throws Exception { MatOfByte mob=new MatOfByte(); Imgcodecs.imencode(".jpg", matrix, mob); byte ba[]=mob.toArray(); BufferedImage bi=ImageIO.read(new ByteArrayInputStream(ba)); return bi; } /** * @param args the command line arguments */ public static void main(String args[]) { /* Set the Nimbus look and feel */ //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) "> /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel. * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html */ try { for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) { if ("Nimbus".equals(info.getName())) { javax.swing.UIManager.setLookAndFeel(info.getClassName()); break; } } } catch (ClassNotFoundException ex) { java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } catch (InstantiationException ex) { java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } catch (IllegalAccessException ex) { java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } catch (javax.swing.UnsupportedLookAndFeelException ex) { java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } //</editor-fold> /* Create and display the form */ java.awt.EventQueue.invokeLater(new Runnable() { public void run() { try { new NewJFrame().setVisible(true); } catch (IOException ex) { Logger.getLogger(NewJFrame.class.getName()).log(Level.SEVERE, null, ex); } catch (Exception ex) { Logger.getLogger(NewJFrame.class.getName()).log(Level.SEVERE, null, ex); } } }); } // Variables declaration - do not modify private javax.swing.JLabel jLabel1; private javax.swing.JMenu jMenu1; private javax.swing.JMenu jMenu2; private javax.swing.JMenuBar jMenuBar1; private javax.swing.JMenuItem jMenuItem1; private javax.swing.JScrollPane jScrollPane1; private javax.swing.JSlider jSlider1; // End of variables declaration }
Kinerja Aplikasi
Untuk kinerja aplikasi tidak ada lag karena operasi resize secara langsung menggunakan OpenCV berupa object class Mat.