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1 /*
2 * Copyright 2003 Sun Microsystems, Inc. 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. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any questions.
24 */
25
26 package javax.imageio.plugins.bmp;
27
28 import java.util.Locale;
29 import javax.imageio.ImageWriteParam;
30
31 import com.sun.imageio.plugins.bmp.BMPConstants;
32
33 /**
34 * A subclass of <code>ImageWriteParam</code> for encoding images in
35 * the BMP format.
36 *
37 * <p> This class allows for the specification of various parameters
38 * while writing a BMP format image file. By default, the data layout
39 * is bottom-up, such that the pixels are stored in bottom-up order,
40 * the first scanline being stored last.
41 *
42 * <p>The particular compression scheme to be used can be specified by using
43 * the <code>setCompressionType()</code> method with the appropriate type
44 * string. The compression scheme specified will be honored if and only if it
45 * is compatible with the type of image being written. If the specified
46 * compression scheme is not compatible with the type of image being written
47 * then the <code>IOException</code> will be thrown by the BMP image writer.
48 * If the compression type is not set explicitly then <code>getCompressionType()</code>
49 * will return <code>null</code>. In this case the BMP image writer will select
50 * a compression type that supports encoding of the given image without loss
51 * of the color resolution.
52 * <p>The compression type strings and the image type(s) each supports are
53 * listed in the following
54 * table:
55 *
56 * <p><table border=1>
57 * <caption><b>Compression Types</b></caption>
58 * <tr><th>Type String</th> <th>Description</th> <th>Image Types</th></tr>
59 * <tr><td>BI_RGB</td> <td>Uncompressed RLE</td> <td><= 8-bits/sample</td></tr>
60 * <tr><td>BI_RLE8</td> <td>8-bit Run Length Encoding</td> <td><= 8-bits/sample</td></tr>
61 * <tr><td>BI_RLE4</td> <td>4-bit Run Length Encoding</td> <td><= 4-bits/sample</td></tr>
62 * <tr><td>BI_BITFIELDS</td> <td>Packed data</td> <td> 16 or 32 bits/sample</td></tr>
63 * </table>
64 */
65 public class BMPImageWriteParam extends ImageWriteParam {
66
67 private boolean topDown = false;
68
69 /**
70 * Constructs a <code>BMPImageWriteParam</code> set to use a given
71 * <code>Locale</code> and with default values for all parameters.
72 *
73 * @param locale a <code>Locale</code> to be used to localize
74 * compression type names and quality descriptions, or
75 * <code>null</code>.
76 */
77 public BMPImageWriteParam(Locale locale) {
78 super(locale);
79
80 // Set compression types ("BI_RGB" denotes uncompressed).
81 compressionTypes = BMPConstants.compressionTypeNames;
82
83 // Set compression flag.
84 canWriteCompressed = true;
85 compressionMode = MODE_COPY_FROM_METADATA;
86 compressionType = compressionTypes[BMPConstants.BI_RGB];
87 }
88
89 /**
90 * Constructs an <code>BMPImageWriteParam</code> object with default
91 * values for all parameters and a <code>null</code> <code>Locale</code>.
92 */
93 public BMPImageWriteParam() {
94 this(null);
95 }
96
97 /**
98 * If set, the data will be written out in a top-down manner, the first
99 * scanline being written first.
100 *
101 * @param topDown whether the data are written in top-down order.
102 */
103 public void setTopDown(boolean topDown) {
104 this.topDown = topDown;
105 }
106
107 /**
108 * Returns the value of the <code>topDown</code> parameter.
109 * The default is <code>false</code>.
110 *
111 * @return whether the data are written in top-down order.
112 */
113 public boolean isTopDown() {
114 return topDown;
115 }
116 }