Java tutorial
/* * Copyright (c) 1995 - 2008 Sun Microsystems, Inc. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * - Neither the name of Sun Microsystems nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ import java.awt.Component; import java.awt.Dimension; import java.awt.Graphics; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.WindowAdapter; import java.awt.event.WindowEvent; import java.awt.image.BufferedImage; import java.awt.image.BufferedImageOp; import java.awt.image.ByteLookupTable; import java.awt.image.ConvolveOp; import java.awt.image.Kernel; import java.awt.image.LookupOp; import java.io.File; import java.io.IOException; import java.util.TreeSet; import javax.imageio.ImageIO; import javax.swing.JComboBox; import javax.swing.JFileChooser; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel; public class SaveImage extends Component implements ActionListener { String descs[] = { "Original", "Convolve : LowPass", "Convolve : Sharpen", "LookupOp", }; int opIndex; private BufferedImage bi, biFiltered; int w, h; public static final float[] SHARPEN3x3 = { // sharpening filter kernel 0.f, -1.f, 0.f, -1.f, 5.f, -1.f, 0.f, -1.f, 0.f }; public static final float[] BLUR3x3 = { 0.1f, 0.1f, 0.1f, // low-pass filter // kernel 0.1f, 0.2f, 0.1f, 0.1f, 0.1f, 0.1f }; public SaveImage() { try { bi = ImageIO.read(new File("bld.jpg")); w = bi.getWidth(null); h = bi.getHeight(null); if (bi.getType() != BufferedImage.TYPE_INT_RGB) { BufferedImage bi2 = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB); Graphics big = bi2.getGraphics(); big.drawImage(bi, 0, 0, null); biFiltered = bi = bi2; } } catch (IOException e) { System.out.println("Image could not be read"); System.exit(1); } } public Dimension getPreferredSize() { return new Dimension(w, h); } String[] getDescriptions() { return descs; } void setOpIndex(int i) { opIndex = i; } public void paint(Graphics g) { filterImage(); g.drawImage(biFiltered, 0, 0, null); } int lastOp; public void filterImage() { BufferedImageOp op = null; if (opIndex == lastOp) { return; } lastOp = opIndex; switch (opIndex) { case 0: biFiltered = bi; /* original */ return; case 1: /* low pass filter */ case 2: /* sharpen */ float[] data = (opIndex == 1) ? BLUR3x3 : SHARPEN3x3; op = new ConvolveOp(new Kernel(3, 3, data), ConvolveOp.EDGE_NO_OP, null); break; case 3: /* lookup */ byte lut[] = new byte[256]; for (int j = 0; j < 256; j++) { lut[j] = (byte) (256 - j); } ByteLookupTable blut = new ByteLookupTable(0, lut); op = new LookupOp(blut, null); break; } /* * Rather than directly drawing the filtered image to the destination, * filter it into a new image first, then that filtered image is ready for * writing out or painting. */ biFiltered = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB); op.filter(bi, biFiltered); } /* Return the formats sorted alphabetically and in lower case */ public String[] getFormats() { String[] formats = ImageIO.getWriterFormatNames(); TreeSet<String> formatSet = new TreeSet<String>(); for (String s : formats) { formatSet.add(s.toLowerCase()); } return formatSet.toArray(new String[0]); } public void actionPerformed(ActionEvent e) { JComboBox cb = (JComboBox) e.getSource(); if (cb.getActionCommand().equals("SetFilter")) { setOpIndex(cb.getSelectedIndex()); repaint(); } else if (cb.getActionCommand().equals("Formats")) { /* * Save the filtered image in the selected format. The selected item will * be the name of the format to use */ String format = (String) cb.getSelectedItem(); /* * Use the format name to initialise the file suffix. Format names * typically correspond to suffixes */ File saveFile = new File("savedimage." + format); JFileChooser chooser = new JFileChooser(); chooser.setSelectedFile(saveFile); int rval = chooser.showSaveDialog(cb); if (rval == JFileChooser.APPROVE_OPTION) { saveFile = chooser.getSelectedFile(); /* * Write the filtered image in the selected format, to the file chosen * by the user. */ try { ImageIO.write(biFiltered, format, saveFile); } catch (IOException ex) { } } } }; public static void main(String s[]) { JFrame f = new JFrame("Save Image Sample"); f.addWindowListener(new WindowAdapter() { public void windowClosing(WindowEvent e) { System.exit(0); } }); SaveImage si = new SaveImage(); f.add("Center", si); JComboBox choices = new JComboBox(si.getDescriptions()); choices.setActionCommand("SetFilter"); choices.addActionListener(si); JComboBox formats = new JComboBox(si.getFormats()); formats.setActionCommand("Formats"); formats.addActionListener(si); JPanel panel = new JPanel(); panel.add(choices); panel.add(new JLabel("Save As")); panel.add(formats); f.add("South", panel); f.pack(); f.setVisible(true); } }