IPaletteMapper.java

/*
  IPaletteMapper.java

  (c) 2011-2016 Edward Swartz

  All rights reserved. This program and the accompanying materials
  are made available under the terms of the Eclipse Public License v1.0
  which accompanies this distribution, and is available at
  http://www.eclipse.org/legal/epl-v10.html
 */
package org.ejs.gui.images;

import java.awt.image.BufferedImage;
import java.util.TreeMap;

public interface IPaletteMapper extends IPaletteColorMapper, IColorMapper {
	/**
	 * Get number of colors (range of indices for mapColor and getClosestPalettePixel)
	 */
	int getNumColors();

	/**
	 * Get the palette against which the mapping occurs.
	 * This palette object must match the one that is changed
	 * if the palette is adjusted during mapping via
	 * {@link ImageImport#optimizeForNColorsAndRebuildPalette(BufferedImage, IMapColor)}.
	 * @return palette of size {@link #getNumColors()}
	 */
	byte[][] getPalette();
	
	/**
	 * Get the minimal distance between colors in the palette.
	 */
	int getMinimalPaletteDistance();

	/**
	 * @return
	 */
	TreeMap<Integer, byte[]> getGreyToRgbMap();
	
	/**
	 * Return an RGB triplet corresponding to the luminance
	 * of the incoming color RGB triplet, in a mode where
	 * all colors are rendered as greyscale.
	 * 
	 * Obviously, the incoming color trivially fulfills this requirement.
	 * But the intent here is to return a canonical RGB triplet
	 * which will allow reducing a full-color gamut into a
	 * set of 199 RGB values to allow for better palette matching.
	 * 
	 * @param pixel
	 * @return pixel which is greyscale but whose luminance matches @pixel 
	 */
	int getPixelForGreyscaleMode(int pixel);

	/**
	 * @param nrgb
	 * @return
	 */
	byte[] getRgbToGreyForGreyscaleMode(byte[] nrgb);
}