Source for gnu.javax.imageio.bmp.EncodeRGB4

   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: }