/** *************************************************************
 *
 * Read in the GIF to generate color cube for the array.  If 
 * this is just an GIF this function will initialize the LUT 
 * with the colors of the imageas long as there are fewer than 
 * 256 colors (the MAX for a GIF)
 *
 * @param file The input image file
 * @returns boolean Indicates initialization success
 * 
 */
public boolean init( String file )
{
        Hashtable ht = null;
        Image proto = null;
  	Canvas can = null;
        MediaTracker t = null;
        PixelGrabber pg = null;
        Toolkit tk = null;
        int n=0;

        try
        {
            ht = new Hashtable();
            can = new Canvas();
            tk = can.getToolkit();
            proto = tk.getImage( file );

            t = new MediaTracker(this);
	    t.addImage( proto, 0 );
            t.waitForAll();

            int w = proto.getWidth(null);
            int h = proto.getHeight(null);
            int pix[] = new int[w*h];

            pg = new PixelGrabber(proto, 0, 0, w, h, pix, 0, w);
            while(!(pg.grabPixels())) 
            {
              Thread.sleep(100);
            }

            // Insert into hash table to nuke duplicates
            while (n<(pix.length))
            {
               Integer iobj = new Integer(pix[n++]);
               ht.put(iobj, iobj);
            }

            t.removeImage( proto );
            proto.flush();

            t = null;
            proto = null;
            tk = null;
            can = null;


            // Create byte array.
            n = ht.size();
            if ( n>MAXCOLORS )
                throw new Exception( "CIUNetscapeColorCube::init> too many colors" );

            //
            // Since we need 8 bits for an index into this LUT,  the 
            // GIF we create will expect 256 possible values... therefore, 
            // we allocate these 256 but only fill the 1st 216.  The rest 
            // are black.
            //
            m_aColors = new byte[ 256*3 ];
            m_cColors = n;


            // Fill byte array
            Enumeration enum = ht.keys();
            n=0;
            while(enum.hasMoreElements() && (n<216))
            {
               int i =  ((Integer)(enum.nextElement())).intValue();

               byte r = (byte)(( i >> 16) & 0xFF);
               byte g = (byte)(( i >> 8 ) & 0xFF);
               byte b = (byte)(  i        & 0xFF);

               m_aColors[ n*3   ] = r;
               m_aColors[ n*3+1 ] = g;
               m_aColors[ n*3+2 ] = b;
               ++n;
            }

        }
        catch(Exception e)
        {
           System.err.println("CIUNetscapeColorCube::init> Exception: " + e );
           e.printStackTrace();
           return false;
        } 

        return true;
}