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diff --git a/common/rfb/TightPalette.h b/common/rfb/TightPalette.h
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+/* Copyright (C) 2000-2005 Constantin Kaplinsky.  All Rights Reserved.
+ *    
+ * This 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.
+ * 
+ * This software 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 this software; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
+ * USA.
+ */
+
+//
+// TightPalette class is a container for ordered color values. Colors
+// are keys in a hash where values are frequency counts. Also, there
+// is a list where colors are always sorted by these counts (more
+// frequent first).
+//
+
+#ifndef __RFB_TIGHTPALETTE_H__
+#define __RFB_TIGHTPALETTE_H__
+
+#include <string.h>
+#include <rdr/types.h>
+
+namespace rfb {
+
+  struct TightColorList {
+    TightColorList *next;
+    int idx;
+    rdr::U32 rgb;
+  };
+
+  struct TightPaletteEntry {
+    TightColorList *listNode;
+    int numPixels;
+  };
+
+  class TightPalette {
+
+  protected:
+
+    // FIXME: Bigger hash table? Better hash function?
+    inline static int hashFunc(rdr::U32 rgb) {
+      return (rgb ^ (rgb >> 13)) & 0xFF;
+    }
+
+  public:
+
+    TightPalette(int maxColors = 254);
+
+    //
+    // Re-initialize the object. This does not change maximum number
+    // of colors.
+    //
+    void reset();
+
+    //
+    // Set limit on the number of colors in the palette. Note that
+    // this value cannot exceed 254.
+    //
+    void setMaxColors(int maxColors);
+
+    //
+    // Insert new color into the palette, or increment its counter if
+    // the color is already there. Returns new number of colors, or
+    // zero if the palette is full. If the palette becomes full, it
+    // reports zero colors and cannot be used any more without calling
+    // reset().
+    //
+    int insert(rdr::U32 rgb, int numPixels);
+
+    //
+    // Return number of colors in the palette.
+    //
+    inline int getNumColors() const {
+      return m_numColors;
+    }
+
+    //
+    // Return the color specified by its index in the palette.
+    //
+    inline rdr::U32 getEntry(int i) const {
+      return (i < m_numColors) ? m_entry[i].listNode->rgb : (rdr::U32)-1;
+    }
+
+    //
+    // Return the pixel counter of the color specified by its index.
+    //
+    inline int getCount(int i) const {
+      return (i < m_numColors) ? m_entry[i].numPixels : 0;
+    }
+
+    //
+    // Return the index of a specified color.
+    //
+    inline rdr::U8 getIndex(rdr::U32 rgb) const {
+      TightColorList *pnode = m_hash[hashFunc(rgb)];
+      while (pnode != NULL) {
+        if (pnode->rgb == rgb) {
+          return (rdr::U8)pnode->idx;
+        }
+        pnode = pnode->next;
+      }
+      return 0xFF;              // no such color
+    }
+
+  protected:
+
+    int m_maxColors;
+    int m_numColors;
+
+    TightPaletteEntry m_entry[256];
+    TightColorList *m_hash[256];
+    TightColorList m_list[256];
+
+  };
+
+} // namespace rfb
+
+#endif // __RFB_TIGHTPALETTE_H__