libjava/classpath/gnu/javax/imageio/bmp/EncodeRGB4.java

   1 /* EncodeRGB4.java --
   2    Copyright (C) 2006 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19 02110-1301 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package gnu.javax.imageio.bmp;
  40
  41 import java.awt.image.BufferedImage;
  42 import java.awt.image.PixelGrabber;
  43 import java.io.IOException;
  44
  45 import javax.imageio.IIOImage;
  46 import javax.imageio.ImageWriteParam;
  47 import javax.imageio.metadata.IIOMetadata;
  48 import javax.imageio.stream.ImageOutputStream;
  49
  50 public class EncodeRGB4
  51     extends BMPEncoder
  52 {
  53   protected BMPInfoHeader infoHeader;
  54   protected BMPFileHeader fileHeader;
  55   protected long offset;
  56
  57   /**
  58    * Constructs an instance of this class.
  59    *
  60    * @param fh - the file header to use.
  61    * @param ih - the info header to use.
  62    */
  63   public EncodeRGB4(BMPFileHeader fh, BMPInfoHeader ih)
  64   {
  65     super();
  66     fileHeader = fh;
  67     infoHeader = ih;
  68     offset = BMPFileHeader.SIZE + BMPInfoHeader.SIZE;
  69   }
  70
  71   /**
  72    * The image encoder.
  73    *
  74    * @param o - the image output stream
  75    * @param streamMetadata - metadata associated with this stream, or
  76    * null
  77    * @param image - an IIOImage containing image data.
  78    * @param param - image writing parameters, or null
  79    * @exception IOException if a write error occurs
  80    */
  81   public void encode(ImageOutputStream o, IIOMetadata streamMetadata,
  82                      IIOImage image, ImageWriteParam param) throws IOException
  83   {
  84     int size;
  85     int value;
  86     int j;
  87     int rowCount;
  88     int rowIndex;
  89     int lastRowIndex;
  90     int[] bitmap;
  91     byte rgb[] = new byte[1];
  92     size = (infoHeader.biWidth * infoHeader.biHeight) - 1;
  93     rowCount = 1;
  94     rowIndex = size - infoHeader.biWidth;
  95     lastRowIndex = rowIndex;
  96     try
  97       {
  98         bitmap = new int[infoHeader.biWidth * infoHeader.biHeight];
  99         PixelGrabber pg = new PixelGrabber((BufferedImage) image.getRenderedImage(),
 100                                            0, 0, infoHeader.biWidth,
 101                                            infoHeader.biHeight, bitmap, 0,
 102                                            infoHeader.biWidth);
 103         pg.grabPixels();
 104
 105         for (j = 0; j < size; j++)
 106           {
 107             value = bitmap[rowIndex];
 108
 109             rgb[0] = (byte) (value & 0xFF);
 110
 111             o.write(rgb);
 112             if (rowCount == infoHeader.biWidth)
 113               {
 114                 rowCount = 1;
 115                 rowIndex = lastRowIndex - infoHeader.biWidth;
 116                 lastRowIndex = rowIndex;
 117               }
 118             else
 119               rowCount++;
 120             rowIndex++;
 121           }
 122       }
 123     catch (Exception wb)
 124       {
 125         wb.printStackTrace();
 126       }
 127   }
 128 }