1 /*
   2  * Copyright (c) 2003, 2013, 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 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 import com.sun.imageio.plugins.bmp.BMPCompressionTypes;
  33 
  34 /**
  35  * A subclass of {@code ImageWriteParam} for encoding images in
  36  * the BMP format.
  37  *
  38  * <p> This class allows for the specification of various parameters
  39  * while writing a BMP format image file.  By default, the data layout
  40  * is bottom-up, such that the pixels are stored in bottom-up order,
  41  * the first scanline being stored last.
  42  *
  43  * <p>The particular compression scheme to be used can be specified by using
  44  * the {@code setCompressionType()} method with the appropriate type
  45  * string.  The compression scheme specified will be honored if and only if it
  46  * is compatible with the type of image being written. If the specified
  47  * compression scheme is not compatible with the type of image being written
  48  * then the {@code IOException} will be thrown by the BMP image writer.
  49  * If the compression type is not set explicitly then {@code getCompressionType()}
  50  * will return {@code null}. In this case the BMP image writer will select
  51  * a compression type that supports encoding of the given image without loss
  52  * of the color resolution.
  53  * <p>The compression type strings and the image type(s) each supports are
  54  * listed in the following
  55  * table:
  56  *
  57  * <table border=1>
  58  * <caption><b>Compression Types</b></caption>
  59  * <tr><th>Type String</th> <th>Description</th>  <th>Image Types</th></tr>
  60  * <tr><td>BI_RGB</td>  <td>Uncompressed RLE</td> <td>{@literal <= } 8-bits/sample</td></tr>
  61  * <tr><td>BI_RLE8</td> <td>8-bit Run Length Encoding</td> <td>{@literal <=} 8-bits/sample</td></tr>
  62  * <tr><td>BI_RLE4</td> <td>4-bit Run Length Encoding</td> <td>{@literal <=} 4-bits/sample</td></tr>
  63  * <tr><td>BI_BITFIELDS</td> <td>Packed data</td> <td> 16 or 32 bits/sample</td></tr>
  64  * </table>
  65  */
  66 public class BMPImageWriteParam extends ImageWriteParam {
  67 
  68     private boolean topDown = false;
  69 
  70     /**
  71      * Constructs a {@code BMPImageWriteParam} set to use a given
  72      * {@code Locale} and with default values for all parameters.
  73      *
  74      * @param locale a {@code Locale} to be used to localize
  75      * compression type names and quality descriptions, or
  76      * {@code null}.
  77      */
  78     public BMPImageWriteParam(Locale locale) {
  79         super(locale);
  80 
  81         // Set compression types ("BI_RGB" denotes uncompressed).
  82         compressionTypes = BMPCompressionTypes.getCompressionTypes();
  83 
  84         // Set compression flag.
  85         canWriteCompressed = true;
  86         compressionMode = MODE_COPY_FROM_METADATA;
  87         compressionType = compressionTypes[BMPConstants.BI_RGB];
  88     }
  89 
  90     /**
  91      * Constructs an {@code BMPImageWriteParam} object with default
  92      * values for all parameters and a {@code null Locale}.
  93      */
  94     public BMPImageWriteParam() {
  95         this(null);
  96     }
  97 
  98     /**
  99      * If set, the data will be written out in a top-down manner, the first
 100      * scanline being written first.
 101      *
 102      * @param topDown whether the data are written in top-down order.
 103      */
 104     public void setTopDown(boolean topDown) {
 105         this.topDown = topDown;
 106     }
 107 
 108     /**
 109      * Returns the value of the {@code topDown} parameter.
 110      * The default is {@code false}.
 111      *
 112      * @return whether the data are written in top-down order.
 113      */
 114     public boolean isTopDown() {
 115         return topDown;
 116     }
 117 }