Java tutorial
import java.awt.*; import java.awt.image.BufferedImage; /* * This file is part of the Caliph and Emir project: http://www.SemanticMetadata.net. * * Caliph & Emir is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * Caliph & Emir is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with Caliph & Emir; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * Copyright statement: * -------------------- * (c) 2002-2006 by Mathias Lux (mathias@juggle.at) * http://www.juggle.at, http://www.SemanticMetadata.net */ /** * Some little helper methods.<br> * This file is part of the Caliph and Emir project: http://www.SemanticMetadata.net * <br>Date: 02.02.2006 * <br>Time: 23:33:36 * * @author Mathias Lux, mathias@juggle.at */ public class ImageUtils { /** * Scales down an image into a box of maxSideLenght x maxSideLength. * @param image the image to scale down. It remains untouched. * @param maxSideLength the maximum side length of the scaled down instance. Has to be > 0. * @return the scaled image, the */ public static BufferedImage scaleImage(BufferedImage image, int maxSideLength) { assert (maxSideLength > 0); double originalWidth = image.getWidth(); double originalHeight = image.getHeight(); double scaleFactor = 0.0; if (originalWidth > originalHeight) { scaleFactor = ((double) maxSideLength / originalWidth); } else { scaleFactor = ((double) maxSideLength / originalHeight); } // create smaller image BufferedImage img = new BufferedImage((int) (originalWidth * scaleFactor), (int) (originalHeight * scaleFactor), BufferedImage.TYPE_INT_RGB); // fast scale (Java 1.4 & 1.5) Graphics g = img.getGraphics(); g.drawImage(image, 0, 0, img.getWidth(), img.getHeight(), null); return img; } }