/*
* @(#)JPEGImageDecoder.java 1.6 95/11/28 Jim Graham
*
* Copyright (c) 1994 Sun Microsystems, Inc. All Rights Reserved.
*
* Permission to use, copy, modify, and distribute this software
* and its documentation for NON-COMMERCIAL purposes and without
* fee is hereby granted provided that this copyright notice
* appears in all copies. Please refer to the file "copyright.html"
* for further important copyright and licensing information.
*
* SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF
* THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
* TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR
* ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
* DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
*/
/*-
* Reads JPEG images from an InputStream and reports the
* image data to an InputStreamImageSource object.
*
* The native implementation of the JPEG image decoder was adapted from
* release 6 of the free JPEG software from the Independent JPEG Group.
*/
package sun.awt.image;
import java.util.Vector;
import java.util.Hashtable;
import java.io.InputStream;
import java.io.IOException;
import java.awt.image.*;
import java.lang.SecurityManager;
/**
* JPEG Image converter
*
* @version 1.6 28 Nov 1995
* @author Jim Graham
*/
public class JPEGImageDecoder extends ImageDecoder {
private static ColorModel RGBcolormodel;
private static ColorModel Graycolormodel;
static {
SecurityManager.setScopePermission();
System.loadLibrary("jpeg");
SecurityManager.resetScopePermission();
RGBcolormodel = new DirectColorModel(24, 0xff0000, 0xff00, 0xff);
byte g[] = new byte[256];
for (int i = 0; i < 256; i++) {
g[i] = (byte) i;
}
Graycolormodel = new IndexColorModel(8, 256, g, g, g);
}
private native void readImage(InputStream is, byte buf[])
throws ImageFormatException;
PixelStore store;
Hashtable props = new Hashtable();
public JPEGImageDecoder(InputStreamImageSource src, InputStream is) {
super(src, is);
}
public synchronized boolean catchupConsumer(InputStreamImageSource src,
ImageConsumer ic)
{
return ((store == null) || store.replay(src, ic));
}
public synchronized void makeStore(int width, int height, boolean gray) {
if (gray) {
store = new PixelStore8(width, height);
} else {
store = new PixelStore32(width, height);
}
}
/**
* An error has occurred. Throw an exception.
*/
private static void error(String s1) throws ImageFormatException {
throw new ImageFormatException(s1);
}
public boolean sendHeaderInfo(int width, int height,
boolean gray, boolean multipass) {
source.setDimensions(width, height);
makeStore(width, height, gray);
source.setProperties(props);
store.setProperties(props);
ColorModel colormodel = gray ? Graycolormodel : RGBcolormodel;
source.setColorModel(colormodel);
store.setColorModel(colormodel);
int flags = hintflags;
if (!multipass) {
flags |= ImageConsumer.SINGLEPASS;
}
source.setHints(hintflags);
store.setHints(hintflags);
return true;
}
public boolean sendPixels(int pixels[], int y) {
int count = source.setPixels(0, y, pixels.length, 1, RGBcolormodel,
pixels, 0, pixels.length);
if (store.setPixels(0, y, pixels.length, 1,
pixels, 0, pixels.length)) {
count++;
}
return (count > 0);
}
public boolean sendPixels(byte pixels[], int y) {
int count = source.setPixels(0, y, pixels.length, 1, Graycolormodel,
pixels, 0, pixels.length);
if (store.setPixels(0, y, pixels.length, 1,
pixels, 0, pixels.length)) {
count++;
}
return (count > 0);
}
/**
* produce an image from the stream.
*/
public void produceImage() throws IOException, ImageFormatException {
try {
readImage(input, new byte[1024]);
store.imageComplete();
if (store.getBitState() != PixelStore.BITS_LOST) {
source.setPixelStore(store);
}
source.imageComplete(ImageConsumer.STATICIMAGEDONE);
} finally {
try {
input.close();
} catch (IOException e) {
}
}
}
/**
* The ImageConsumer hints flag for a JPEG image.
*/
private static final int hintflags =
ImageConsumer.TOPDOWNLEFTRIGHT | ImageConsumer.COMPLETESCANLINES |
ImageConsumer.SINGLEFRAME;
}