protected PixelBandAccessor(PixelBand pixelBand)
 {
     this.pixelBand = pixelBand as Band <T>;
     if (this.pixelBand == null)
     {
         throw new System.ArgumentException("pixelBand is not a Band<T>");
     }
 }
        private Converter <TRasterBand, TPixelBand> converter;  // TRasterBand -> TPixelBand

        public PixelBandSetter(PixelBand pixelBand,
                               Converter <TRasterBand, TPixelBand> converter)
            : base(pixelBand)
        {
            this.converter = converter;
        }