// ymageBMPParser.java
// (C) 2007 by Michael Peter Christen; mc@yacy.net, Frankfurt a. M., Germany
// first published 15.07.2007 on http://yacy.net
//
// $LastChangedDate: 2006-04-02 22:40:07 +0200 (So, 02 Apr 2006) $
// $LastChangedRevision: 1986 $
// $LastChangedBy: orbiter $
//
// LICENSE
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program 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 for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
package de.anomic.ymage;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import javax.imageio.ImageIO;
public class ymageBMPParser {
// this is a implementation of http://de.wikipedia.org/wiki/Windows_Bitmap
// file offsets
private static int FILEHEADER_offset = 0;
private static int INFOHEADER_offset = 14;
public static int INFOHEADER_size = 40;
// compression tags
static int BI_RGB = 0;
//private static int BI_RLE8 = 1;
//private static int BI_RLE4 = 2;
//private static int BI_BITFIELDS = 3;
private final IMAGEMAP imagemap;
//boolean debugmode = false;
public static final boolean isBMP(final byte[] source) {
// check the file magic
return (source != null) && (source.length >= 2) && (source[0] == 'B') && (source[1] == 'M');
}
public ymageBMPParser(final byte[] source) {
// read info-header
final int bfOffBits = DWORD(source, FILEHEADER_offset + 10);
final INFOHEADER infoheader = new INFOHEADER(source, INFOHEADER_offset);
final COLORTABLE colortable = new COLORTABLE(source, INFOHEADER_offset + INFOHEADER_size, infoheader);
// check consistency with bfOffBits
assert bfOffBits == INFOHEADER_offset + 40 + colortable.colorbytes : "bfOffBits = " + bfOffBits + ", colorbytes = " + colortable.colorbytes;
assert infoheader.biSizeImage <= source.length - bfOffBits : "bfOffBits = " + bfOffBits + ", biSizeImage = " + infoheader.biSizeImage + ", source.length = " + source.length;
imagemap = new IMAGEMAP(source, bfOffBits, infoheader.biWidth, infoheader.biHeight, infoheader.biCompression, infoheader.biBitCount, colortable);
}
public BufferedImage getImage() {
return imagemap.image;
}
public static final int DWORD(final byte[] b, final int offset) {
if (offset + 3 >= b.length) return 0;
int ret = (b[offset + 3] & 0xff);
ret = (ret << 8) | (b[offset + 2] & 0xff);
ret = (ret << 8) | (b[offset + 1] & 0xff);
ret = (ret << 8) | (b[offset] & 0xff);
return ret;
}
public static final int WORD(final byte[] b, final int offset) {
final int ret = ((b[offset + 1] & 0xff) << 8) | (b[offset] & 0xff);
return ret;
}
public static final int BYTE(final byte[] b, final int offset) {
final int ret = (b[offset] & 0xff);
return ret;
}
public static class INFOHEADER {
public int biWidth, biHeight, biBitCount, biCompression, biSizeImage, biClrUsed;
public INFOHEADER(final byte[] s, final int offset) {
// read info-header
biWidth = DWORD(s, offset + 4);
biHeight = DWORD(s, offset + 8);
biBitCount = WORD(s, offset + 14);
biCompression = WORD(s, offset + 16);
biSizeImage = DWORD(s, offset + 20);
biClrUsed = DWORD(s, offset + 32);
}
}
public static class COLORTABLE {
public int colorbytes;
public int[] colorindex;
public COLORTABLE(final byte[] s, final int offset, final INFOHEADER infoheader) {
// read colortable
colorbytes = 0; // for consistency check
if (infoheader.biClrUsed == 0) {
if ((infoheader.biBitCount == 1) || (infoheader.biBitCount == 4) || (infoheader.biBitCount == 8)) {
colorindex = new int[1 << infoheader.biBitCount];
colorbytes = 4 * colorindex.length;
int color;
for (int i = 0; i < colorindex.length; i++) {
// translate BGR into RGB color Scheme
color = 0xffffff & DWORD(s, offset + 4 * i);
colorindex[i] = color;
}
} else {
colorindex = null;
}
} else {
colorindex = new int[infoheader.biClrUsed];
colorbytes = 4 * colorindex.length;
int color;
for (int i = 0; i < colorindex.length; i++) {
// translate BGR into RGB color Scheme
color = 0xffffff & DWORD(s, offset + 4 * i);
colorindex[i] = color;
//if (debugmode) System.out.println("Color " + i + " = " + Integer.toHexString(colorindex[i]));
}
}
}
}
public static class IMAGEMAP {
public BufferedImage image;
public IMAGEMAP(final byte[] s, final int offset, final int width, final int height, final int compression, final int bitcount, final COLORTABLE colortable) {
// parse picture content
if ((width != 0) && (height != 0)) {
image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
if (compression == BI_RGB) {
if (bitcount == 1) parseBMP1(s, offset, width, height, colortable);
else if (bitcount == 4) parseBMP4(s, offset, width, height, colortable);
else if (bitcount == 8) parseBMP8(s, offset, width, height, colortable);
else if (bitcount == 24) parseBMP24(s, offset, width, height);
else if (bitcount == 32) parseBMP32(s, offset, width, height);
else System.out.println("unsupported BMP format: biCompression = " + compression + ", biBitCount = " + bitcount);
} else {
System.out.println("unsupported BMP format: biCompression = " + compression + ", biBitCount = " + bitcount);
}
}
}
private void parseBMP1(final byte[] s, final int offset, final int width, final int height, final COLORTABLE colortable) {
int n = 0;
int b;
for (int rows = 0; rows < height; rows++) {
for (int columns = 0; columns < width; columns = columns + 8) {
if (offset + n >= s.length) return; // emergency break
b = (s[offset + n] & 0xff);
n++;
image.setRGB(columns, (height - rows - 1), colortable.colorindex[(b & 0x80) >> 7]);
image.setRGB(columns + 1, (height - rows - 1), colortable.colorindex[(b & 0x40) >> 6]);
image.setRGB(columns + 2, (height - rows - 1), colortable.colorindex[(b & 0x20) >> 5]);
image.setRGB(columns + 3, (height - rows - 1), colortable.colorindex[(b & 0x10) >> 4]);
image.setRGB(columns + 4, (height - rows - 1), colortable.colorindex[(b & 0x08) >> 3]);
image.setRGB(columns + 5, (height - rows - 1), colortable.colorindex[(b & 0x04) >> 2]);
image.setRGB(columns + 6, (height - rows - 1), colortable.colorindex[(b & 0x02) >> 1]);
image.setRGB(columns + 7, (height - rows - 1), colortable.colorindex[ b & 0x01]);
}
n += fill4(n);
}
}
private void parseBMP4(final byte[] s, final int offset, final int width, final int height, final COLORTABLE colortable) {
int n = 0;
int b;
for (int rows = 0; rows < height; rows++) {
for (int columns = 0; columns < width; columns = columns + 2) {
if (offset + n >= s.length) return; // emergency break
b = (s[offset + n] & 0xff);
n++;
image.setRGB(columns, (height - rows - 1), colortable.colorindex[(b & 0xf0) >> 4]);
image.setRGB(columns + 1, (height - rows - 1), colortable.colorindex[b & 0xf]);
}
n += fill4(n);
}
}
private void parseBMP8(final byte[] s, final int offset, final int width, final int height, final COLORTABLE colortable) {
int n = 0;
for (int rows = 0; rows < height; rows++) {
for (int columns = 0; columns < width; columns++) {
if (offset + n >= s.length) return; // emergency break
image.setRGB(columns, (height - rows - 1), colortable.colorindex[(s[offset + n] & 0xff)]);
n++;
}
n += fill4(n);
}
}
private void parseBMP24(final byte[] s, final int offset, final int width, final int height) {
int n = 0;
for (int rows = 0; rows < height; rows++) {
for (int columns = 0; columns < width; columns++) {
if (offset + n + 3 >= s.length) return; // emergency break
image.setRGB(columns, (height - rows - 1), 0xffffff & DWORD(s, offset + n));
n += 3;
}
n += fill4(n);
}
}
private void parseBMP32(final byte[] s, final int offset, final int width, final int height) {
int n = 0;
for (int rows = 0; rows < height; rows++) {
for (int columns = 0; columns < width; columns++) {
if (offset + n + 3 >= s.length) return; // emergency break
image.setRGB(columns, (height - rows - 1), 0xffffff & DWORD(s, offset + n));
n += 4;
}
}
}
private final int fill4(final int x) {
final int r = x % 4;
if (r == 0) return 0;
return 4 - r;
}
}
public static void main(final String[] args) {
// read a bmp and write it as png
System.setProperty("java.awt.headless", "true");
final File in = new File(args[0]);
final File out = new File(args[1]);
final byte[] file = new byte[(int) in.length()];
FileInputStream fis = null;
try {
fis = new FileInputStream(in);
fis.read(file);
} catch (final FileNotFoundException e) {
e.printStackTrace();
} catch (final IOException e) {
e.printStackTrace();
}
final ymageBMPParser parser = new ymageBMPParser(file);
try {
ImageIO.write(parser.getImage(), "PNG", out);
} catch (final IOException e) {
e.printStackTrace();
}
}
}