org.apache.commons.imaging.formats.png.chunks.PngChunkPlte Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.imaging.formats.png.chunks;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import org.apache.commons.imaging.ImageReadException;
import org.apache.commons.imaging.formats.png.GammaCorrection;
import static org.apache.commons.imaging.common.BinaryFunctions.*;
public class PngChunkPlte extends PngChunk {
private final int[] rgb;
public PngChunkPlte(final int length, final int chunkType, final int crc, final byte[] bytes)
throws ImageReadException, IOException {
super(length, chunkType, crc, bytes);
final ByteArrayInputStream is = new ByteArrayInputStream(bytes);
if ((length % 3) != 0) {
throw new ImageReadException("PLTE: wrong length: " + length);
}
final int count = length / 3;
rgb = new int[count];
for (int i = 0; i < count; i++) {
final int red = readByte("red[" + i + "]", is,
"Not a Valid Png File: PLTE Corrupt");
final int green = readByte("green[" + i + "]", is,
"Not a Valid Png File: PLTE Corrupt");
final int blue = readByte("blue[" + i + "]", is,
"Not a Valid Png File: PLTE Corrupt");
rgb[i] = 0xff000000 | ((0xff & red) << 16) | ((0xff & green) << 8)
| ((0xff & blue) << 0);
}
}
public int[] getRgb() {
return rgb;
}
public int getRGB(final int index) throws ImageReadException {
if ((index < 0) || (index >= rgb.length)) {
throw new ImageReadException("PNG: unknown Palette reference: "
+ index);
}
return rgb[index];
}
// public void printPalette() {
// Debug.debug();
// Debug.debug("palette");
// for (int i = 0; i < rgb.length; i++) {
// Debug.debug("\t" + "palette[" + i + "];", rgb[i] + " (0x"
// + Integer.toHexString(rgb[i]) + ")");
//
// }
// Debug.debug();
// }
public void correct(final GammaCorrection gammaCorrection) {
for (int i = 0; i < rgb.length; i++) {
rgb[i] = gammaCorrection.correctARGB(rgb[i]);
}
}
}