//
// Nenya library - tools for developing networked games
// Copyright (C) 2002-2012 Three Rings Design, Inc., All Rights Reserved
// https://github.com/threerings/nenya
//
// This library is free software; you can redistribute it and/or modify it
// under the terms of the GNU Lesser General Public License as published
// by the Free Software Foundation; either version 2.1 of the License, or
// (at your option) any later version.
//
// This library 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
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
package com.threerings.resource;
import java.io.DataOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.RandomAccessFile;
import java.nio.ByteBuffer;
import java.nio.IntBuffer;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;
import java.awt.Point;
import java.awt.image.BufferedImage;
import java.awt.image.DataBuffer;
import java.awt.image.DataBufferByte;
import java.awt.image.IndexColorModel;
import java.awt.image.PixelInterleavedSampleModel;
import java.awt.image.WritableRaster;
import com.samskivert.io.StreamUtil;
/**
* Provides routines for writing and reading uncompressed 8-bit color
* mapped images in a manner that is extremely fast and generates a
* minimal amount of garbage during the loading process.
*/
public class FastImageIO
{
/**
* A suffix for use when storing raw images in bundles or on the file system.
*/
public static final String FILE_SUFFIX = ".raw";
/**
* Returns true if the supplied image is of a format that is supported by the fast image I/O
* services, false if not.
*/
public static boolean canWrite (BufferedImage image)
{
return (image.getColorModel() instanceof IndexColorModel) &&
(image.getRaster().getDataBuffer() instanceof DataBufferByte);
}
/**
* Writes the supplied image to the supplied output stream.
*
* @exception IOException thrown if an error occurs writing to the output stream.
*/
public static void write (BufferedImage image, OutputStream out)
throws IOException
{
DataOutputStream dout = new DataOutputStream(out);
// write the image dimensions
int width = image.getWidth(), height = image.getHeight();
dout.writeInt(width);
dout.writeInt(height);
// write the color model information
IndexColorModel cmodel = (IndexColorModel)image.getColorModel();
int tpixel = cmodel.getTransparentPixel();
dout.writeInt(tpixel);
int msize = cmodel.getMapSize();
int[] map = new int[msize];
cmodel.getRGBs(map);
dout.writeInt(msize);
for (int element : map) {
dout.writeInt(element);
}
// write the raster data
DataBufferByte dbuf = (DataBufferByte)image.getRaster().getDataBuffer();
byte[] data = dbuf.getData();
if (data.length != width * height) {
String errmsg = "Raster data not same size as image! [" +
width + "x" + height + " != " + data.length + "]";
throw new IllegalStateException(errmsg);
}
dout.write(data);
dout.flush();
}
/**
* Reads an image from the supplied file (which must contain an image previously written via a
* call to {@link #write}).
*
* @exception IOException thrown if an error occurs reading from the file.
*/
public static BufferedImage read (File file)
throws IOException
{
RandomAccessFile raf = new RandomAccessFile(file, "r");
FileChannel fchan = raf.getChannel();
try {
MappedByteBuffer mbuf = fchan.map(FileChannel.MapMode.READ_ONLY, 0, file.length());
return read(mbuf);
} finally {
fchan.close();
raf.close();
}
}
/**
* Reads an image from the supplied input stream (which must return the image format previously
* written via a call to {@link #write}).
*
* @exception IOException thrown if an error occurs reading from the file.
*/
public static BufferedImage read (InputStream in)
throws IOException
{
return read(ByteBuffer.wrap(StreamUtil.toByteArray(in)));
}
/**
* Reads an image from the supplied byte buffer (which must return the image format previously
* written via a call to {@link #write}).
*
* @exception IOException thrown if an error occurs reading from the file.
*/
public static BufferedImage read (ByteBuffer byteBuffer)
throws IOException
{
// read in our integer fields
IntBuffer ibuf = byteBuffer.asIntBuffer();
int width = ibuf.get();
int height = ibuf.get();
/* int tpixel = */ ibuf.get();
int msize = ibuf.get();
if (width > Short.MAX_VALUE || width < 0 || height > Short.MAX_VALUE || height < 0) {
throw new IOException("Bogus image size " + width + "x" + height);
}
IndexColorModel cmodel;
synchronized (_origin) { // any old object will do
// make sure our colormap array is big enough
if (_cmap == null || _cmap.length < msize) {
_cmap = new int[msize];
}
// read in the data and create our colormap
ibuf.get(_cmap, 0, msize);
cmodel = new IndexColorModel(
8, msize, _cmap, 0, DataBuffer.TYPE_BYTE, null);
}
// advance the byte buffer accordingly
byteBuffer.position(ibuf.position() * 4);
// read in the image data itself
byte[] data = new byte[width*height];
byteBuffer.get(data);
// create the image from our component parts
DataBuffer dbuf = new DataBufferByte(data, data.length, 0);
int[] offsets = new int[] { 0 };
PixelInterleavedSampleModel smodel =
new PixelInterleavedSampleModel(
DataBuffer.TYPE_BYTE, width, height, 1, width, offsets);
WritableRaster raster = WritableRaster.createWritableRaster(smodel, dbuf, _origin);
return new BufferedImage(cmodel, raster, false, null);
}
/** Used when loading our color map. */
protected static int[] _cmap;
/** Used when creating our writable raster. */
protected static Point _origin = new Point(0, 0);
}