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	/*
	* Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code 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
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.awt.image;


	/**
	* This class defines a lookup table object. The output of a
	* lookup operation using an object of this class is interpreted
	* as an unsigned byte quantity. The lookup table contains byte
	* data arrays for one or more bands (or components) of an image,
	* and it contains an offset which will be subtracted from the
	* input values before indexing the arrays. This allows an array
	* smaller than the native data size to be provided for a
	* constrained input. If there is only one array in the lookup
	* table, it will be applied to all bands.
	*
	* @see ShortLookupTable
	* @see LookupOp
	*/
	public class ByteLookupTable extends LookupTable {

	/**
	* Constants
	*/

	byte data[][];

	/**
	* Constructs a ByteLookupTable object from an array of byte
	* arrays representing a lookup table for each
	* band. The offset will be subtracted from input
	* values before indexing into the arrays. The number of
	* bands is the length of the data argument. The
	* data array for each band is stored as a reference.
	* @param offset the value subtracted from the input values
	* before indexing into the arrays
	* @param data an array of byte arrays representing a lookup
	* table for each band
	* @throws IllegalArgumentException if <code>offset</code> is
	* is less than 0 or if the length of <code>data</code>
	* is less than 1
	*/
	public ByteLookupTable(int offset, byte data[][]) {
	super(offset,data.length);
	numComponents = data.length;
	numEntries = data[0].length;
	this.data = new byte[numComponents][];
	// Allocate the array and copy the data reference
	for (int i=0; i < numComponents; i++) {
	this.data[i] = data[i];
	}
	}

	/**
	* Constructs a ByteLookupTable object from an array
	* of bytes representing a lookup table to be applied to all
	* bands. The offset will be subtracted from input
	* values before indexing into the array.
	* The data array is stored as a reference.
	* @param offset the value subtracted from the input values
	* before indexing into the array
	* @param data an array of bytes
	* @throws IllegalArgumentException if <code>offset</code> is
	* is less than 0 or if the length of <code>data</code>
	* is less than 1
	*/
	public ByteLookupTable(int offset, byte data[]) {
	super(offset,data.length);
	numComponents = 1;
	numEntries = data.length;
	this.data = new byte[1][];
	this.data[0] = data;
	}

	/**
	* Returns the lookup table data by reference. If this ByteLookupTable
	* was constructed using a single byte array, the length of the returned
	* array is one.
	* @return the data array of this <code>ByteLookupTable</code>.
	*/
	public final byte[][] getTable(){
	return data;
	}

	/**
	* Returns an array of samples of a pixel, translated with the lookup
	* table. The source and destination array can be the same array.
	* Array <code>dst</code> is returned.
	*
	* @param src the source array.
	* @param dst the destination array. This array must be at least as
	* long as <code>src</code>. If <code>dst</code> is
	* <code>null</code>, a new array will be allocated having the
	* same length as <code>src</code>.
	* @return the array <code>dst</code>, an <code>int</code> array of
	* samples.
	* @exception ArrayIndexOutOfBoundsException if <code>src</code> is
	* longer than <code>dst</code> or if for any element
	* <code>i</code> of <code>src</code>,
	* <code>src[i]-offset</code> is either less than zero or
	* greater than or equal to the length of the lookup table
	* for any band.
	*/
	public int[] lookupPixel(int[] src, int[] dst){
	if (dst == null) {
	// Need to alloc a new destination array
	dst = new int[src.length];
	}

	if (numComponents == 1) {
	// Apply one LUT to all bands
	for (int i=0; i < src.length; i++) {
	int s = src[i] - offset;
	if (s < 0) {
	throw new ArrayIndexOutOfBoundsException("src["+i+
	"]-offset is "+
	"less than zero");
	}
	dst[i] = (int) data[0][s];
	}
	}
	else {
	for (int i=0; i < src.length; i++) {
	int s = src[i] - offset;
	if (s < 0) {
	throw new ArrayIndexOutOfBoundsException("src["+i+
	"]-offset is "+
	"less than zero");
	}
	dst[i] = (int) data[i][s];
	}
	}
	return dst;
	}

	/**
	* Returns an array of samples of a pixel, translated with the lookup
	* table. The source and destination array can be the same array.
	* Array <code>dst</code> is returned.
	*
	* @param src the source array.
	* @param dst the destination array. This array must be at least as
	* long as <code>src</code>. If <code>dst</code> is
	* <code>null</code>, a new array will be allocated having the
	* same length as <code>src</code>.
	* @return the array <code>dst</code>, an <code>int</code> array of
	* samples.
	* @exception ArrayIndexOutOfBoundsException if <code>src</code> is
	* longer than <code>dst</code> or if for any element
	* <code>i</code> of <code>src</code>,
	* {@code (src[i]&0xff)-offset} is either less than
	* zero or greater than or equal to the length of the
	* lookup table for any band.
	*/
	public byte[] lookupPixel(byte[] src, byte[] dst){
	if (dst == null) {
	// Need to alloc a new destination array
	dst = new byte[src.length];
	}

	if (numComponents == 1) {
	// Apply one LUT to all bands
	for (int i=0; i < src.length; i++) {
	int s = (src[i]&0xff) - offset;
	if (s < 0) {
	throw new ArrayIndexOutOfBoundsException("src["+i+
	"]-offset is "+
	"less than zero");
	}
	dst[i] = data[0][s];
	}
	}
	else {
	for (int i=0; i < src.length; i++) {
	int s = (src[i]&0xff) - offset;
	if (s < 0) {
	throw new ArrayIndexOutOfBoundsException("src["+i+
	"]-offset is "+
	"less than zero");
	}
	dst[i] = data[i][s];
	}
	}
	return dst;
	}

	}

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