001 /*
002 * GeoAPI - Java interfaces for OGC/ISO standards
003 * http://www.geoapi.org
004 *
005 * Copyright (C) 2008-2012 Open Geospatial Consortium, Inc.
006 * All Rights Reserved. http://www.opengeospatial.org/ogc/legal
007 *
008 * Permission to use, copy, and modify this software and its documentation, with
009 * or without modification, for any purpose and without fee or royalty is hereby
010 * granted, provided that you include the following on ALL copies of the software
011 * and documentation or portions thereof, including modifications, that you make:
012 *
013 * 1. The full text of this NOTICE in a location viewable to users of the
014 * redistributed or derivative work.
015 * 2. Notice of any changes or modifications to the OGC files, including the
016 * date changes were made.
017 *
018 * THIS SOFTWARE AND DOCUMENTATION IS PROVIDED "AS IS," AND COPYRIGHT HOLDERS MAKE
019 * NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
020 * TO, WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OR THAT
021 * THE USE OF THE SOFTWARE OR DOCUMENTATION WILL NOT INFRINGE ANY THIRD PARTY
022 * PATENTS, COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS.
023 *
024 * COPYRIGHT HOLDERS WILL NOT BE LIABLE FOR ANY DIRECT, INDIRECT, SPECIAL OR
025 * CONSEQUENTIAL DAMAGES ARISING OUT OF ANY USE OF THE SOFTWARE OR DOCUMENTATION.
026 *
027 * The name and trademarks of copyright holders may NOT be used in advertising or
028 * publicity pertaining to the software without specific, written prior permission.
029 * Title to copyright in this software and any associated documentation will at all
030 * times remain with copyright holders.
031 */
032 package org.opengis.style;
033
034 import org.opengis.annotation.Extension;
035 import org.opengis.annotation.XmlElement;
036 import org.opengis.filter.expression.Expression;
037
038
039 /**
040 * <p>The ContrastEnhancement object defines contrast enhancement for a channel of
041 * a false-color image or for a color image.
042 * </p>
043 *
044 * <p>In the case of a color image, the relative grayscale brightness of a pixel
045 * color is used. ?Normalize? means to stretch the contrast so that the
046 * dimmest color is stretched to black and the brightest color is stretched to
047 * white, with all colors in between stretched out linearly. ?Histogram? means
048 * to stretch the contrast based on a histogram of how many colors are at each
049 * brightness level on input, with the goal of producing equal number of
050 * pixels in the image at each brightness level on output. This has the
051 * effect of revealing many subtle ground features. A ?GammaValue? tells how
052 * much to brighten (value greater than 1.0) or dim (value less than 1.0) an
053 * image. The default GammaValue is 1.0 (no change). If none of Normalize,
054 * Histogram, or GammaValue are selected in a ContrastEnhancement, then no
055 * enhancement is performed.
056 * </p>
057 *
058 * @version <A HREF="http://www.opengeospatial.org/standards/symbol">Symbology Encoding Implementation Specification 1.1.0</A>
059 * @author Open Geospatial Consortium
060 * @author Ian Turton, CCG
061 * @author Johann Sorel (Geomatys)
062 * @since GeoAPI 2.2
063 */
064 @XmlElement("ContrastEnhancement")
065 public interface ContrastEnhancement {
066
067 /**
068 * We use a codeList to enable more enchancement type possibilities.
069 */
070 @XmlElement("Normalize,Histogram")
071 public ContrastMethod getMethod();
072
073 /**
074 * A "GammaValue" tells how much to brighten (values
075 * greater than 1.0) or dim (values less than 1.0) an image. The default GammaValue is 1.0
076 * (no change).
077 *
078 * @return Expression to control gamma adjustment, null or Expression.NIL handled as the value 1.0
079 */
080 @XmlElement("GammaValue")
081 Expression getGammaValue();
082
083 /**
084 * calls the visit method of a StyleVisitor
085 *
086 * @param visitor the style visitor
087 */
088 @Extension
089 Object accept(StyleVisitor visitor, Object extraData);
090
091 }