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

   1 package gov.nasa.worldwind.formats.nitfs;
   2
   3 /*
   4 Copyright (C) 2001, 2007 United States Government
   5 as represented by the Administrator of the
   6 National Aeronautics and Space Administration.
   7 All Rights Reserved.
   8 */
   9
  10 /**
  11  * @author Lado Garakanidze
  12  * @version $Id: NitfsImageBand Apr 17, 2007 3:22:33 PM lado
  13  */
  14 class NitfsImageBand
  15 {
  16     private String representation;
  17     private String significanceForImageCategory;
  18     private String imageFilterCondition;
  19     private String stdImageFilterCode;
  20     private short numOfLookupTables;
  21     private short numOfLookupTableEntries;
  22     // public int[]  lookupTablesOffset; // one byte per entry per band
  23     private byte[][] lut;
  24
  25     private boolean isGrayImage;
  26     private boolean hasTransparentEntry;
  27
  28     public boolean isGrayImage()
  29     {
  30         return this.isGrayImage;
  31     }
  32
  33     public boolean isHasTransparentEntry()
  34     {
  35         return this.hasTransparentEntry;
  36     }
  37
  38     public String getRepresentation()
  39     {
  40         return this.representation;
  41     }
  42
  43     public short getNumOfLookupTables()
  44     {
  45         return this.numOfLookupTables;
  46     }
  47
  48     public short getNumOfLookupTableEntries()
  49     {
  50         return this.numOfLookupTableEntries;
  51     }
  52
  53     public NitfsImageBand(java.nio.ByteBuffer buffer)
  54     {
  55         this.representation = NitfsUtil.getString(buffer, 2);
  56         this.significanceForImageCategory = NitfsUtil.getString(buffer, 6);
  57         this.imageFilterCondition = NitfsUtil.getString(buffer, 1);
  58         this.stdImageFilterCode = NitfsUtil.getString(buffer, 3);
  59         this.numOfLookupTables = NitfsUtil.getShortNumeric(buffer, 1);
  60         this.numOfLookupTableEntries = NitfsUtil.getShortNumeric(buffer, 5);
  61         if (0 < this.numOfLookupTables && 0 < this.numOfLookupTableEntries)
  62         {
  63             this.lut = new byte[this.numOfLookupTables][this.numOfLookupTableEntries];
  64             for (int j = 0; j < this.numOfLookupTables; j++)
  65             {
  66                 buffer.get(this.lut[j], 0, this.numOfLookupTableEntries);
  67             }
  68         }
  69
  70         this.isGrayImage = (1 == this.numOfLookupTables);
  71         this.hasTransparentEntry = (217 == this.numOfLookupTableEntries);
  72     }
  73
  74     public final int lookupR5G6B5(int colorIndex)
  75     {
  76         int r, g, b;
  77         if (3 == this.numOfLookupTables)
  78         {
  79             r = (0x00FF & this.lut[0][colorIndex]) >> 3;
  80             g = (0x00FF & this.lut[1][colorIndex]) >> 2;
  81             b = (0x00FF & this.lut[2][colorIndex]) >> 3;
  82         }
  83         else
  84         {
  85             int gray = 0x00FF & this.lut[0][ colorIndex ];
  86             r = gray >> 3;
  87             g = gray >> 2;
  88             b = gray >> 3;
  89         }
  90         return 0x00FFFF & ((r << 11) | (g << 5) | b );
  91     }
  92
  93
  94     public final int lookupRGB(int colorIndex)
  95     {
  96         int r, g, b;
  97         if (3 == this.numOfLookupTables)
  98         {
  99             r = (0x00FF & this.lut[0][colorIndex]);
 100             g = (0x00FF & this.lut[1][colorIndex]);
 101             b = (0x00FF & this.lut[2][colorIndex]);
 102         }
 103         else
 104         {
 105             r = g = b = 0x00FF & this.lut[0][ colorIndex ];
 106         }
 107         return (int) (0x00FFFFFFL & (long)((r << 16) | (g << 8) | b ));
 108     }
 109
 110     public final int lookupGray(int colorIndex)
 111     {
 112
 113         if (3 == this.numOfLookupTables)
 114         {
 115             int r = (0x00FF & this.lut[0][colorIndex]);
 116             int g = (0x00FF & this.lut[1][colorIndex]);
 117             int b = (0x00FF & this.lut[2][colorIndex]);
 118
 119             return (30 * r + 59 * g + 11 * b)/100;
 120         }
 121         else
 122         {
 123             return (0x00FF & this.lut[0][colorIndex]);
 124         }
 125     }
 126 }