1/*
2 * Copyright (c) 1995, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25/*-
26 *      Reads JPEG images from an InputStream and reports the
27 *      image data to an InputStreamImageSource object.
28 *
29 * The native implementation of the JPEG image decoder was adapted from
30 * release 6 of the free JPEG software from the Independent JPEG Group.
31 */
32package sun.awt.image;
33
34import java.util.Vector;
35import java.util.Hashtable;
36import java.io.InputStream;
37import java.io.IOException;
38import java.awt.image.*;
39
40/**
41 * JPEG Image converter
42 *
43 * @author Jim Graham
44 */
45public class JPEGImageDecoder extends ImageDecoder {
46    private static ColorModel RGBcolormodel;
47    private static ColorModel ARGBcolormodel;
48    private static ColorModel Graycolormodel;
49
50    private static final Class<?> InputStreamClass = InputStream.class;
51    private static native void initIDs(Class<?> InputStreamClass);
52
53    private ColorModel colormodel;
54
55    static {
56        java.security.AccessController.doPrivileged(
57            new java.security.PrivilegedAction<Void>() {
58                public Void run() {
59                    System.loadLibrary("javajpeg");
60                    return null;
61                }
62            });
63        initIDs(InputStreamClass);
64        RGBcolormodel = new DirectColorModel(24, 0xff0000, 0xff00, 0xff);
65        ARGBcolormodel = ColorModel.getRGBdefault();
66        byte g[] = new byte[256];
67        for (int i = 0; i < 256; i++) {
68            g[i] = (byte) i;
69        }
70        Graycolormodel = new IndexColorModel(8, 256, g, g, g);
71    }
72
73    private native void readImage(InputStream is, byte buf[])
74        throws ImageFormatException, IOException;
75
76    Hashtable<String, Object> props = new Hashtable<>();
77
78    public JPEGImageDecoder(InputStreamImageSource src, InputStream is) {
79        super(src, is);
80    }
81
82    /**
83     * An error has occurred. Throw an exception.
84     */
85    private static void error(String s1) throws ImageFormatException {
86        throw new ImageFormatException(s1);
87    }
88
89    public boolean sendHeaderInfo(int width, int height,
90                                  boolean gray, boolean hasalpha,
91                                  boolean multipass)
92    {
93        setDimensions(width, height);
94
95        setProperties(props);
96        if (gray) {
97            colormodel = Graycolormodel;
98        } else {
99            if (hasalpha) {
100                colormodel = ARGBcolormodel;
101            } else {
102                colormodel = RGBcolormodel;
103            }
104        }
105
106        setColorModel(colormodel);
107
108        int flags = hintflags;
109        if (!multipass) {
110            flags |= ImageConsumer.SINGLEPASS;
111        }
112        setHints(hintflags);
113        headerComplete();
114
115        return true;
116    }
117
118    public boolean sendPixels(int pixels[], int y) {
119        int count = setPixels(0, y, pixels.length, 1, colormodel,
120                              pixels, 0, pixels.length);
121        if (count <= 0) {
122            aborted = true;
123        }
124        return !aborted;
125    }
126
127    public boolean sendPixels(byte pixels[], int y) {
128        int count = setPixels(0, y, pixels.length, 1, colormodel,
129                              pixels, 0, pixels.length);
130        if (count <= 0) {
131            aborted = true;
132        }
133        return !aborted;
134    }
135
136    /**
137     * produce an image from the stream.
138     */
139    public void produceImage() throws IOException, ImageFormatException {
140        try {
141            readImage(input, new byte[1024]);
142            if (!aborted) {
143                imageComplete(ImageConsumer.STATICIMAGEDONE, true);
144            }
145        } catch (IOException e) {
146            if (!aborted) {
147                throw e;
148            }
149        } finally {
150            close();
151        }
152    }
153
154    /**
155     * The ImageConsumer hints flag for a JPEG image.
156     */
157    private static final int hintflags =
158        ImageConsumer.TOPDOWNLEFTRIGHT | ImageConsumer.COMPLETESCANLINES |
159        ImageConsumer.SINGLEFRAME;
160}
161