1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.imaging.palette;
18
19 import org.apache.commons.imaging.ImagingException;
20
21 /**
22 * Color palette.
23 */
24 public interface Palette {
25
26 /**
27 * Gets the color for a given palette index.
28 *
29 * @param index the palette index to look up
30 * @return the color in ARGB format
31 */
32 int getEntry(int index);
33
34 /**
35 * Gets the palette index for a given color.
36 *
37 * @param rgb the color to look up
38 * @return the palette index
39 * @throws ImagingException if it fails to read the palette index
40 */
41 int getPaletteIndex(int rgb) throws ImagingException;
42
43 /**
44 * Gets the number of entries in the palette.
45 *
46 * @return the number of palette entries
47 */
48 int length();
49
50 }