gov/nasa/worldwind/formats/nitfs/Cadrg2DdsCompress.java

   1 package gov.nasa.worldwind.formats.nitfs;
   2
   3 import gov.nasa.worldwind.*;
   4
   5 import java.nio.*;
   6 /*
   7 Copyright (C) 2001, 2007 United States Government
   8 as represented by the Administrator of the
   9 National Aeronautics and Space Administration.
  10 All Rights Reserved.
  11 */
  12
  13 /**
  14  * @author Lado Garakanidze
  15  * @version $Id: Cadrg2DdsCompress Apr 23, 2007 11:00:07 AM lado
  16  */
  17 class Cadrg2DdsCompress extends AbstractRpf2DdsCompress
  18 {
  19     public DDSBlock4x4 compressDxt1Block4x4(NitfsImageBand imageBand, byte[] pixelCodes, boolean hasTransparentPixels)
  20     {
  21         int[]   pixels565 = new int[16];
  22         Color[] colors565 = new Color[16];
  23         for(int i = 0; i < pixelCodes.length; i++ )
  24         {
  25             pixels565[i] = imageBand.lookupR5G6B5( 0x00FF & pixelCodes[i] );
  26             colors565[i] = DDSConverter.getColor565( pixels565[i] );
  27         }
  28
  29         int[] extremaIndices = determineExtremeColors( colors565 );
  30
  31         if(pixels565[extremaIndices[0]] < pixels565[extremaIndices[1]])
  32         {
  33             int t = extremaIndices[0];
  34             extremaIndices[0] = extremaIndices[1];
  35             extremaIndices[1] = t;
  36         }
  37
  38         return  new DDSBlock4x4(
  39             (short) pixels565[extremaIndices[0]],
  40             (short) pixels565[extremaIndices[1]],
  41             (int) DDSConverter.computeBitMask(colors565, extremaIndices)
  42             );
  43     }
  44 }