code: public Double getValue(GriddedTile griddedTile, short pixelValue) {
  		int unsignedPixelValue = getUnsignedPixelValue(pixelValue);
  		Double value = getValue(griddedTile, unsignedPixelValue);
  		return value;
  	}
docs: Get the coverage data value for the "unsigned short" pixel value
  
  @param griddedTile
  gridded tile
  @param pixelValue
  pixel value as an unsigned short
  @return coverage data value