/*
* Copyright (c) 1997, 2016, 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.
*
* 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 org.netbeans.jemmy.util;
import java.awt.Color;
import java.awt.image.BufferedImage;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.zip.DataFormatException;
import java.util.zip.Inflater;
import org.netbeans.jemmy.JemmyException;
/**
* Allows to load PNG graphical file.
*
* @author Alexandre Iline
*/
public class PNGDecoder extends Object {
InputStream in;
/**
* Constructs a PNGDecoder object.
*
* @param in input stream to read PNG image from.
*/
public PNGDecoder(InputStream in) {
this.in = in;
}
byte read() throws IOException {
byte b = (byte) in.read();
return b;
}
int readInt() throws IOException {
byte b[] = read(4);
return (((b[0] & 0xff) << 24)
+ ((b[1] & 0xff) << 16)
+ ((b[2] & 0xff) << 8)
+ ((b[3] & 0xff)));
}
byte[] read(int count) throws IOException {
byte[] result = new byte[count];
for (int i = 0; i < count; i++) {
result[i] = read();
}
return result;
}
boolean compare(byte[] b1, byte[] b2) {
if (b1.length != b2.length) {
return false;
}
for (int i = 0; i < b1.length; i++) {
if (b1[i] != b2[i]) {
return false;
}
}
return true;
}
void checkEquality(byte[] b1, byte[] b2) {
if (!compare(b1, b2)) {
throw (new JemmyException("Format error"));
}
}
/**
* Decodes image from an input stream passed into constructor.
*
* @return a BufferedImage object
* @throws IOException
*/
public BufferedImage decode() throws IOException {
byte[] id = read(12);
checkEquality(id, new byte[]{-119, 80, 78, 71, 13, 10, 26, 10, 0, 0, 0, 13});
byte[] ihdr = read(4);
checkEquality(ihdr, "IHDR".getBytes());
int width = readInt();
int height = readInt();
BufferedImage result = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
byte[] head = read(5);
int mode;
if (compare(head, new byte[]{1, 0, 0, 0, 0})) {
mode = PNGEncoder.BW_MODE;
} else if (compare(head, new byte[]{8, 0, 0, 0, 0})) {
mode = PNGEncoder.GREYSCALE_MODE;
} else if (compare(head, new byte[]{8, 2, 0, 0, 0})) {
mode = PNGEncoder.COLOR_MODE;
} else {
throw (new JemmyException("Format error"));
}
readInt();//!!crc
int size = readInt();
byte[] idat = read(4);
checkEquality(idat, "IDAT".getBytes());
byte[] data = read(size);
Inflater inflater = new Inflater();
inflater.setInput(data, 0, size);
int color;
try {
switch (mode) {
case PNGEncoder.BW_MODE: {
int bytes = width / 8;
if ((width % 8) != 0) {
bytes++;
}
byte colorset;
byte[] row = new byte[bytes];
for (int y = 0; y < height; y++) {
inflater.inflate(new byte[1]);
inflater.inflate(row);
for (int x = 0; x < bytes; x++) {
colorset = row[x];
for (int sh = 0; sh < 8; sh++) {
if (x * 8 + sh >= width) {
break;
}
if ((colorset & 0x80) == 0x80) {
result.setRGB(x * 8 + sh, y, Color.white.getRGB());
} else {
result.setRGB(x * 8 + sh, y, Color.black.getRGB());
}
colorset <<= 1;
}
}
}
}
break;
case PNGEncoder.GREYSCALE_MODE: {
byte[] row = new byte[width];
for (int y = 0; y < height; y++) {
inflater.inflate(new byte[1]);
inflater.inflate(row);
for (int x = 0; x < width; x++) {
color = row[x];
result.setRGB(x, y, (color << 16) + (color << 8) + color);
}
}
}
break;
case PNGEncoder.COLOR_MODE: {
byte[] row = new byte[width * 3];
for (int y = 0; y < height; y++) {
inflater.inflate(new byte[1]);
inflater.inflate(row);
for (int x = 0; x < width; x++) {
result.setRGB(x, y,
((row[x * 3 + 0] & 0xff) << 16)
+ ((row[x * 3 + 1] & 0xff) << 8)
+ ((row[x * 3 + 2] & 0xff)));
}
}
}
}
} catch (DataFormatException e) {
throw (new JemmyException("ZIP error", e));
}
readInt();//!!crc
readInt();//0
byte[] iend = read(4);
checkEquality(iend, "IEND".getBytes());
readInt();//!!crc
in.close();
return result;
}
/**
* Decodes image from file.
*
* @param fileName a file to read image from
* @return a BufferedImage instance.
*/
public static BufferedImage decode(String fileName) {
try {
return new PNGDecoder(new FileInputStream(fileName)).decode();
} catch (IOException e) {
throw (new JemmyException("IOException during image reading", e));
}
}
}