import javax.swing.*; import javax.swing.event.*; import java.awt.event.*; import java.awt.*; import java.awt.image.*; import java.awt.Color; import java.net.*; /** * *SThresholdScreen is the user interface to the thresholding algorithm *(newjavasrc.operator.Threshold.java) It is run as an applet embedded in *the file threshld.htm * *@author Konstantinos Koryllos, Judy Robertson SELLIC OnLine, Timothy Sharman */ public class SThresholdScreen extends HistVisionApplet { /** *The current low threshold for the threshold algorithm */ public int lowthresh = 64; /** *The current high threshold for the threshold algorithm */ public int highthresh = 192; //To siginify if the thresholded image is to be inverted or not. private boolean inverted = false; //vision operators required for thresholding private Threshold thresholdalgorithm; //The listeners for the GUI private SliderListener slhigh = new SliderListener(); private SliderListener sllow = new SliderListener(); private ComboListener cltoggle = new ComboListener(); private ButtonListener startbl = new ButtonListener(); private ButtonListener abortbl = new ButtonListener(); private TextListener textListen = new TextListener(); //The layout managers private GridBagLayout mllayout = new GridBagLayout(); private GridBagLayout mrlayout = new GridBagLayout(); private GridBagConstraints midlc = new GridBagConstraints(); private GridBagConstraints midrc = new GridBagConstraints(); //Interface components private JLabel highlabel = new JLabel("High threshold value"); private JLabel lowlabel = new JLabel("Low threshold value"); private JTextField lowbox = new JTextField(4); private JTextField highbox = new JTextField(4); private JSlider highthreshold = new JSlider(JSlider.HORIZONTAL, 0, 255, highthresh); private JSlider lowthreshold = new JSlider(JSlider.HORIZONTAL, 0, 255, lowthresh); private JComboBox toggle = new JComboBox(); private JButton startbutton = new JButton("Apply Threshold"); private JButton abortbutton = new JButton("Abort"); private JLabel time = new JLabel("Time"); private JTextField time_taken = new JTextField(20); public void add_extra() { //initialise the operator constructors thresholdalgorithm = new Threshold(); //Set the layout for the mid panel midc. weighty = 0.5; midc. gridx = 0; midc. gridy = 0; midlayout. setConstraints(lowlabel, midc); mid. add(lowlabel); midc. gridx = 1; midc. gridy = 0; midlayout. setConstraints(lowbox, midc); mid. add(lowbox); lowbox. addActionListener(textListen); lowbox. setText("64"); midc. gridx = 1; midc. gridy = 1; midc. weightx = 0.4; midc. fill = GridBagConstraints. HORIZONTAL; midlayout. setConstraints(lowthreshold, midc); mid. add(lowthreshold); lowthreshold. addChangeListener(sllow); lowthreshold. setMajorTickSpacing(50); lowthreshold. setMinorTickSpacing(5); lowthreshold. setPaintTicks(true); lowthreshold. setPaintLabels(true); midc. weightx = 0; midc. fill = GridBagConstraints.NONE; midc. gridx = 0; midc. gridy = 2; midlayout. setConstraints(highlabel, midc); mid. add(highlabel); midc. gridx = 1; midc. gridy = 2; midlayout. setConstraints(highbox, midc); mid. add(highbox); highbox. addActionListener(textListen); highbox. setText("192"); midc. gridx = 1; midc. gridy = 3; midc. weightx = 0.4; midc. fill = GridBagConstraints. HORIZONTAL; midlayout. setConstraints(highthreshold, midc); mid. add(highthreshold); highthreshold. setMajorTickSpacing(50); highthreshold. setMinorTickSpacing(5); highthreshold. setPaintTicks(true); highthreshold. setPaintLabels(true); highthreshold. addChangeListener(slhigh); midc. weightx = 0; midc. fill = GridBagConstraints.NONE; midc. gridwidth = 1; midc. gridx = 0; midc. gridy = 4; toggle. addItem("Normal"); toggle. addItem("Inverted"); midlayout. setConstraints(toggle, midc); mid. add(toggle); toggle. addActionListener(cltoggle); midc. gridx = 0; midc. gridy = 5; midlayout. setConstraints(startbutton, midc); startbutton. setBackground(Color.green); mid. add(startbutton); startbutton. addActionListener(startbl); midc. gridx = GridBagConstraints.RELATIVE; abortbutton. setBackground(Color.red); midlayout. setConstraints(abortbutton, midc); mid. add(abortbutton); abortbutton. addActionListener(abortbl); midc. gridx = 0; midc. gridy = 6; midlayout. setConstraints(time, midc); mid. add(time); midc. gridx = 1; midc. gridy = 6; midlayout. setConstraints(time_taken, midc); time_taken. setEditable(false); mid. add(time_taken); mid. repaint(); } /** * *Handles the actions performed when combo lists on the interface are selected. * *@param evt The event which caused this object to be called * */ class ComboListener implements ActionListener { public void actionPerformed(ActionEvent evt) { JComboBox cb = (JComboBox) evt.getSource(); if( cb.getSelectedItem().equals("Normal") ) { inverted = false; } else if( cb.getSelectedItem().equals("Inverted") ) { inverted = true; } } } class TextListener implements ActionListener { public void actionPerformed(ActionEvent evt){ JTextField jtf = (JTextField)evt. getSource(); try{ int val = Integer. valueOf (jtf. getText()). intValue(); if(val >= 0 && val <= 255){ if(jtf == lowbox){ lowthreshold. setValue(val); } else if(jtf == highbox){ highthreshold. setValue(val); } } else{ JOptionPane.showMessageDialog(null,("Threshold must lie between 0 and 255"), ("Error!"), JOptionPane.WARNING_MESSAGE); if(jtf == lowbox){ lowthreshold. setValue(64); lowbox. setText("64"); } else if(jtf == highbox){ highthreshold. setValue(192); highbox. setText("192"); } } } catch(NumberFormatException e){ JOptionPane.showMessageDialog(null,("Invalid threshold specified"), ("Error!"), JOptionPane.WARNING_MESSAGE); } } } /** * *Handles the actions performed when sliders on the interface are selected. * *@param evt The event which caused this object to be called * */ class SliderListener implements ChangeListener { public void stateChanged(ChangeEvent evt) { JSlider slide = (JSlider) evt. getSource(); if (histogramalgorithm != null) { if (slide == highthreshold) { highthresh = highthreshold. getValue(); highbox. setText(String. valueOf(highthreshold. getValue())); hist_canvas. highthresh = highthresh; hist_canvas. invalidate(); hist_canvas. repaint(); } if (slide == lowthreshold) { lowthresh = lowthreshold. getValue(); lowbox. setText(String. valueOf(lowthreshold. getValue())); hist_canvas. lowthresh = lowthresh; hist_canvas. invalidate(); hist_canvas. repaint(); } } } } /** * *Handles the actions performed when buttons on the interface are pressed. * *@param evt The event which caused this object to be called * */ class ButtonListener implements ActionListener { public void actionPerformed(ActionEvent evt) { JButton b = (JButton)evt.getSource(); if( b == startbutton ) { time_msec = System.currentTimeMillis(); if(lowthresh > highthresh){ JOptionPane.showMessageDialog(null,("Low threshold must be smaller than high threshold"), ("Error!"), JOptionPane.WARNING_MESSAGE); } else{ dest_1d = thresholdalgorithm. twothreshold(src_1d ,i_w, i_h, lowthresh, highthresh); if (inverted) { dest_1d = thresholdalgorithm. flip_the_pixels(dest_1d, i_w, i_h); } time_msec = System.currentTimeMillis() - time_msec; time_taken.setText(new Long(time_msec).toString()+" msecs"); dest = createImage(new MemoryImageSource(i_w, i_h, dest_1d, 0, i_w)); dest_canvas. updateImage(dest); outsize. setText(d_w+ " x "+d_h); container. validate(); //Add a pixel listener to the new output canvas PixelListener brpl = new PixelListener(); dest_canvas. addMouseMotionListener(brpl); } } else if ( b == abortbutton ) { time_taken. setText(""); } } } public void set_src_image(int [] input_img , int w, int h, String name) { set_src_image2(input_img, w, h, name); //create a new inversion operator thresholdalgorithm = new Threshold(); lowbox. setText("64"); highbox. setText("192"); highthreshold. setValue(192); lowthreshold. setValue(64); } /** *Used by the browser to find out what the applet is for * *@return the function of the applet */ public String getAppletInfo() { return "An applet for thresholding an image :part of the hiprjava.iface package. Written by Judy Robertson, SELLIC OnLine, Timothy Sharman"; } }