1 /*
2 * Copyright (c) 2000, 2017, 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
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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
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20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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24 */
25
26 /**
27 * The main package of the Java Image I/O API.
28 * <p>
29 * Many common image I/O operations may be performed using the static methods of
30 * the {@code ImageIO} class.
31 * <p>
32 * This package contains the basic classes and interfaces for describing the
33 * contents of image files, including metadata and thumbnails
34 * ({@code IIOImage}); for controlling the image reading process
35 * ({@code ImageReader}, {@code ImageReadParam}, and {@code ImageTypeSpecifier})
36 * and image writing process ({@code ImageWriter} and {@code ImageWriteParam});
37 * for performing transcoding between formats ({@code ImageTranscoder}), and for
38 * reporting errors ({@code IIOException}).
39 * <p>
40 * All implementations of javax.imageio provide the following standard image
41 * format plug-ins:
42 * <div>
43 * <table border=1 cellpadding=5 style="margin: 0px auto;" summary="Standard
44 * image format plug-ins">
45 * <tr>
46 * <th> </th><th>Reading</th><th>Writing</th><th>Notes</th>
47 * <th>Metadata</th>
48 * </tr>
49 *
50 * <!-- BMP plugin -->
51 * <tr>
52 * <td><a href="https://msdn.microsoft.com/en-us/library/dd183391.aspx">
53 * BMP</a></td>
54 * <td align='center'>yes</td>
55 * <td align='center'>yes</td>
56 * <td align='center'>none</td>
57 * <td align='center'><a href='metadata/doc-files/bmp_metadata.html'>BMP
58 * metadata format</a></td>
59 * </tr>
60 *
61 * <!-- GIF plugin -->
62 * <tr>
63 * <td><a href="http://www.w3.org/Graphics/GIF/spec-gif89a.txt">GIF</a>
64 * </td>
65 * <td align='center'>yes</td>
66 * <td align='center'>yes</td>
67 * <td align='center'><a href="#gif_plugin_notes">GIF plug-in notes</a>
68 * </td>
69 * <td align='center'><a href='metadata/doc-files/gif_metadata.html'>GIF
70 * metadata format</a></td>
71 * </tr>
72 *
73 * <!-- JPEG plugin -->
74 * <tr>
75 * <td><a href="http://www.jpeg.org">JPEG</a></td>
76 * <td align='center'>yes</td>
77 * <td align='center'>yes</td>
78 * <td align='center'>none</td>
79 * <td align='center'><a href='metadata/doc-files/jpeg_metadata.html'>
80 * JPEG metadata format</a></td>
81 * </tr>
82 *
83 * <!-- PNG plugin -->
84 * <tr>
85 * <td><a href="http://www.libpng.org/pub/png/spec/">PNG</a></td>
86 * <td align='center'>yes</td>
87 * <td align='center'>yes</td>
88 * <td align='center'>none</td>
89 * <td align='center'><a href='metadata/doc-files/png_metadata.html'>PNG
90 * metadata format</a></td>
91 * </tr>
92 *
93 * <!-- TIFF plugin -->
94 * <tr>
95 * <td><a href="https://partners.adobe.com/public/developer/en/tiff/TIFF6.pdf">
96 * TIFF</a></td>
97 * <td align='center'>yes</td>
98 * <td align='center'>yes</td>
99 * <td align='center'><a href='metadata/doc-files/tiff_metadata.html#Reading'>
100 * TIFF plug-in notes</a></td>
101 * <td align='center'><a href='metadata/doc-files/tiff_metadata.html#StreamMetadata'>
102 * TIFF metadata format</a></td>
103 * </tr>
104 *
105 * <!-- WBMP plugin -->
106 * <tr>
107 * <td><a href="http://www.wapforum.org/what/technical/SPEC-WAESpec-19990524.pdf">
108 * WBMP</a></td>
109 * <td align='center'>yes</td>
110 * <td align='center'>yes</td>
111 * <td align='center'>none</td>
112 * <td align='center'><a href='metadata/doc-files/wbmp_metadata.html'>
113 * WBMP metadata format</a></td>
114 * </tr>
115 * </table>
116 * </div>
117 * <BR>
118 * <BR>
119 * <BR>
120 *
121 * <h2> Standard Plug-in Notes</h2>
122 *
123 * <h3><a name="gif_plugin_notes">Standard plug-in for GIF image format</a></h3>
124 * ImageIO provides {@code ImageReader} and {@code ImageWriter}plug-ins for the
125 * <a href="http://www.w3.org/Graphics/GIF/spec-gif89a.txt"> Graphics
126 * Interchange Format (GIF)</a> image format. These are the "standard" GIF
127 * plug-ins, meaning those that are included in the JRE, as distinct from those
128 * included in standard extensions, or 3rd party plug-ins. The following notes
129 * and metadata specification apply to the standard plug-ins.
130 *
131 * <h3>Writing GIF images</h3>
132 * The GIF image writer plug-in guarantees lossless writing for images which
133 * meet the following requirements:
134 * <ul>
135 * <li>the number of bands is 1;</li>
136 * <li>the number of bits per sample is not greater than 8;</li>
137 * <li>the size of a color component is not greater than 8;</li>
138 * </ul>
139 * <p>
140 * By default the GIF writer plug-in creates version "89a" images. This can be
141 * changed to "87a" by explicitly setting the version in the stream metadata
142 * (see
143 * <a href="metadata/doc-files/gif_metadata.html#gif_stream_metadata_format">
144 * GIF Stream Metadata Format Specification</a>).
145 *
146 * <!-- animated images -->
147 * <p>
148 * The GIF writer plug-in supports the creation of animated GIF images through
149 * the standard sequence writing methods defined in the {@code ImageWriter}
150 * class.
151 *
152 * <!-- TODO: add example here -->
153 *
154 * <!-- color tables -->
155 * <p>
156 * A global color table is written to the output stream if one of the following
157 * conditions is met:
158 * <ul>
159 * <li>stream metadata containing a GlobalColorTable element is supplied;
160 * </li>
161 * <li>a sequence is being written and image metadata containing a
162 * LocalColorTable element is supplied for the first image in the sequence;
163 * </li>
164 * <li>image metadata is not supplied or does not contain a LocalColorTable
165 * element.</li>
166 * </ul>
167 * <p>
168 * In the first case the global color table in the stream metadata is used, in
169 * the second the local color table in the image metadata is used, and in the
170 * third a global color table is created from the ColorModel or SampleModel of
171 * the (first) image.
172 * <p>
173 * A local color table is written to the output stream only if image metadata
174 * containing a LocalColorTable element is supplied to the writer, or no image
175 * metadata is supplied to the writer and the local color table which would be
176 * generated from the image itself is not equal to the global color table.
177 * <p>
178 * A Graphic Control Extension block is written to the output stream only if
179 * image metadata containing a GraphicControlExtension element is supplied to
180 * the writer, or no image metadata is supplied and the local color table
181 * generated from the image requires a transparent index. Application, Plain
182 * Text, and Comment Extension blocks are written only if they are supplied to
183 * the writer via image metadata.
184 *
185 * <!-- writing interlaced images -->
186 * <p>
187 * The writing of interlaced images can be controlled by the progressive mode of
188 * the provided {@code ImageWriteParam} instance. If progressive mode is
189 * {@code MODE_DISABLED} then a non-interlaced image will be written. If
190 * progressive mode is {@code MODE_DEFAULT} then an interlaced image will be
191 * written. If progressive mode is {@code MODE_COPY_FROM_METADATA}, then the
192 * metadata setting is used (if it is provided, otherwise an interlaced image
193 * will be written).
194 * <p>
195 * The GIF image writer plug-in supports setting output stream metadata from
196 * metadata supplied to the writer in either the native GIF stream metadata
197 * format
198 * <a href="metadata/doc-files/gif_metadata.html#gif_stream_metadata_format">
199 * javax_imageio_gif_stream_1.0</a> or the standard metadata format
200 * <a href="metadata/doc-files/standard_metadata.html">javax_imageio_1.0</a>,
201 * and setting output image metadata from metadata supplied to the writer in
202 * either the native GIF image metadata format
203 * <a href="metadata/doc-files/gif_metadata.html#gif_image_metadata_format">
204 * javax_imageio_gif_image_1.0</a> or the standard metadata format
205 * <a href="metadata/doc-files/standard_metadata.html">javax_imageio_1.0</a>.
206 * The mapping of standard metadata format to the GIF native stream and image
207 * metadata formats is given in the tables
208 * <a href="metadata/doc-files/gif_metadata.html#mapping">here</a>.
209 *
210 * @since 1.4
211 */
212 package javax.imageio;