/*
* Portions copyright (c) 2003 Sun Microsystems, Inc. All Rights Reserved.
*/
package demos.util;
import java.io.*;
import javax.media.opengl.*;
import com.sun.opengl.utils.*;
// Test harness
import java.awt.image.*;
import javax.swing.*;
/** <p> Reads SGI RGB/RGBA images. </p>
<p> Written from <a href =
"http://astronomy.swin.edu.au/~pbourke/dataformats/sgirgb/">Paul
Bourke's adaptation</a> of the <a href =
"http://astronomy.swin.edu.au/~pbourke/dataformats/sgirgb/sgiversion.html">SGI
specification</a>. </p>
*/
public class SGIImage {
private Header header;
private int format;
private byte[] data;
// Used for decoding RLE-compressed images
private int[] rowStart;
private int[] rowSize;
private int rleEnd;
private byte[] tmpData;
private byte[] tmpRead;
static class Header {
short magic; // IRIS image file magic number
// This should be decimal 474
byte storage; // Storage format
// 0 for uncompressed
// 1 for RLE compression
byte bpc; // Number of bytes per pixel channel
// Legally 1 or 2
short dimension; // Number of dimensions
// Legally 1, 2, or 3
// 1 means a single row, XSIZE long
// 2 means a single 2D image
// 3 means multiple 2D images
short xsize; // X size in pixels
short ysize; // Y size in pixels
short zsize; // Number of channels
// 1 indicates greyscale
// 3 indicates RGB
// 4 indicates RGB and Alpha
int pixmin; // Minimum pixel value
// This is the lowest pixel value in the image
int pixmax; // Maximum pixel value
// This is the highest pixel value in the image
int dummy; // Ignored
// Normally set to 0
String imagename; // Image name; 80 bytes long
// Must be null terminated, therefore at most 79 bytes
int colormap; // Colormap ID
// 0 - normal mode
// 1 - dithered, 3 mits for red and green, 2 for blue, obsolete
// 2 - index colour, obsolete
// 3 - not an image but a colourmap
// 404 bytes char DUMMY Ignored
// Should be set to 0, makes the header 512 bytes.
Header(DataInputStream in) throws IOException {
magic = in.readShort();
storage = in.readByte();
bpc = in.readByte();
dimension = in.readShort();
xsize = in.readShort();
ysize = in.readShort();
zsize = in.readShort();
pixmin = in.readInt();
pixmax = in.readInt();
dummy = in.readInt();
byte[] tmpname = new byte[80];
in.read(tmpname);
int numChars = 0;
while (tmpname[numChars++] != 0);
imagename = new String(tmpname, 0, numChars);
colormap = in.readInt();
byte[] tmp = new byte[404];
in.read(tmp);
}
public String toString() {
return ("magic: " + magic +
" storage: " + (int) storage +
" bpc: " + (int) bpc +
" dimension: " + dimension +
" xsize: " + xsize +
" ysize: " + ysize +
" zsize: " + zsize +
" pixmin: " + pixmin +
" pixmax: " + pixmax +
" imagename: " + imagename +
" colormap: " + colormap);
}
}
private SGIImage(Header header) {
this.header = header;
}
/** Reads an SGI image from the specified file. */
public static SGIImage read(String filename) throws IOException {
return read(new FileInputStream(filename));
}
/** Reads an SGI image from the specified InputStream. */
public static SGIImage read(InputStream in) throws IOException {
DataInputStream dIn = new DataInputStream(new BufferedInputStream(in));
Header header = new Header(dIn);
SGIImage res = new SGIImage(header);
res.decodeImage(dIn);
return res;
}
/** Returns the width of the image. */
public int getWidth() {
return header.xsize;
}
/** Returns the height of the image. */
public int getHeight() {
return header.ysize;
}
/** Returns the OpenGL format for this texture; e.g. GL.GL_BGR or GL.GL_BGRA. */
public int getFormat() {
return format;
}
/** Returns the raw data for this texture in the correct
(bottom-to-top) order for calls to glTexImage2D. */
public byte[] getData() { return data; }
public String toString() {
return header.toString();
}
//----------------------------------------------------------------------
// Internals only below this point
//
private void decodeImage(DataInputStream in) throws IOException {
if (header.storage == 1) {
// Read RLE compression data; row starts and sizes
int x = header.ysize * header.zsize;
rowStart = new int[x];
rowSize = new int[x];
rleEnd = 4 * 2 * x + 512;
for (int i = 0; i < x; i++) {
rowStart[i] = in.readInt();
}
for (int i = 0; i < x; i++) {
rowSize[i] = in.readInt();
}
tmpRead = new byte[header.xsize * 256];
}
tmpData = readAll(in);
int xsize = header.xsize;
int ysize = header.ysize;
int zsize = header.zsize;
int lptr = 0;
data = new byte[xsize * ysize * 4];
byte[] rbuf = new byte[xsize];
byte[] gbuf = new byte[xsize];
byte[] bbuf = new byte[xsize];
byte[] abuf = new byte[xsize];
for (int y = 0; y < ysize; y++) {
if (zsize >= 4) {
getRow(rbuf, y, 0);
getRow(gbuf, y, 1);
getRow(bbuf, y, 2);
getRow(abuf, y, 3);
rgbatorgba(rbuf, gbuf, bbuf, abuf, data, lptr);
} else if (zsize == 3) {
getRow(rbuf, y, 0);
getRow(gbuf, y, 1);
getRow(bbuf, y, 2);
rgbtorgba(rbuf, gbuf, bbuf, data, lptr);
} else if (zsize == 2) {
getRow(rbuf, y, 0);
getRow(abuf, y, 1);
latorgba(rbuf, abuf, data, lptr);
} else {
getRow(rbuf, y, 0);
bwtorgba(rbuf, data, lptr);
}
lptr += 4 * xsize;
}
rowStart = null;
rowSize = null;
tmpData = null;
tmpRead = null;
format = GL.GL_BGRA;
}
private void getRow(byte[] buf, int y, int z) {
if (header.storage == 1) {
int offs = rowStart[y + z * header.ysize] - rleEnd;
System.arraycopy(tmpData, offs, tmpRead, 0, rowSize[y + z * header.ysize]);
int iPtr = 0;
int oPtr = 0;
for (;;) {
byte pixel = tmpRead[iPtr++];
int count = (int) (pixel & 0x7F);
if (count == 0) {
return;
}
if ((pixel & 0x80) != 0) {
while ((count--) > 0) {
buf[oPtr++] = tmpRead[iPtr++];
}
} else {
pixel = tmpRead[iPtr++];
while ((count--) > 0) {
buf[oPtr++] = pixel;
}
}
}
} else {
int offs = (y * header.xsize) + (z * header.xsize * header.ysize);
System.arraycopy(tmpData, offs, buf, 0, header.xsize);
}
}
private void bwtorgba(byte[] b, byte[] dest, int lptr) {
for (int i = 0; i < b.length; i++) {
dest[4 * i + lptr + 0] = b[i];
dest[4 * i + lptr + 1] = b[i];
dest[4 * i + lptr + 2] = b[i];
dest[4 * i + lptr + 3] = (byte) 0xFF;
}
}
private void latorgba(byte[] b, byte[] a, byte[] dest, int lptr) {
for (int i = 0; i < b.length; i++) {
dest[4 * i + lptr + 0] = b[i];
dest[4 * i + lptr + 1] = b[i];
dest[4 * i + lptr + 2] = b[i];
dest[4 * i + lptr + 3] = a[i];
}
}
private void rgbtorgba(byte[] r, byte[] g, byte[] b, byte[] dest, int lptr) {
for (int i = 0; i < b.length; i++) {
dest[4 * i + lptr + 0] = r[i];
dest[4 * i + lptr + 1] = g[i];
dest[4 * i + lptr + 2] = b[i];
dest[4 * i + lptr + 3] = (byte) 0xFF;
}
}
private void rgbatorgba(byte[] r, byte[] g, byte[] b, byte[] a, byte[] dest, int lptr) {
for (int i = 0; i < b.length; i++) {
dest[4 * i + lptr + 0] = r[i];
dest[4 * i + lptr + 1] = g[i];
dest[4 * i + lptr + 2] = b[i];
dest[4 * i + lptr + 3] = a[i];
}
}
private byte[] readAll(DataInputStream in) throws IOException {
byte[] dest = new byte[16384];
int pos = 0;
int numRead = 0;
boolean done = false;
do {
numRead = in.read(dest, pos, dest.length - pos);
if (pos == dest.length) {
// Resize destination buffer
byte[] newDest = new byte[2 * dest.length];
System.arraycopy(dest, 0, newDest, 0, pos);
dest = newDest;
}
if (numRead > 0) {
pos += numRead;
}
done = ((numRead == -1) || (in.available() == 0));
} while (!done);
// Trim destination buffer
if (pos != dest.length) {
byte[] finalDest = new byte[pos];
System.arraycopy(dest, 0, finalDest, 0, pos);
dest = finalDest;
}
return dest;
}
public static void main(String[] args) {
for (int i = 0; i < args.length; i++) {
try {
System.out.println(args[i] + ":");
SGIImage image = SGIImage.read(args[i]);
System.out.println(image);
BufferedImage img = new BufferedImage(image.getWidth(), image.getHeight(), BufferedImage.TYPE_4BYTE_ABGR);
WritableRaster raster = img.getRaster();
DataBufferByte db = (DataBufferByte) raster.getDataBuffer();
byte[] src = image.getData();
byte[] dest = db.getData();
for (int j = 0; j < src.length; j += 4) {
dest[j + 0] = src[j + 3];
dest[j + 1] = src[j + 2];
dest[j + 2] = src[j + 1];
dest[j + 3] = src[j + 0];
}
// System.arraycopy(src, 0, dest, 0, src.length);
ImageIcon icon = new ImageIcon(img);
JLabel label = new JLabel();
label.setIcon(icon);
JFrame frame = new JFrame(args[i]);
frame.getContentPane().add(label);
frame.pack();
frame.show();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}