Application: gvSIG desktop » gvSIG raster

/* gvSIG. Geographic Information System of the Valencian Government

 *

 * Copyright (C) 2007-2008 Infrastructures and Transports Department

 * of the Valencian Government (CIT)

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2

 * of the License, or (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,

 * MA  02110-1301, USA.

 *

 */

package org.gvsig.raster.impl.grid.filter.enhancement;

import org.gvsig.fmap.dal.coverage.dataset.Buffer;

import org.gvsig.fmap.dal.coverage.datastruct.Params;

import org.gvsig.fmap.dal.coverage.exception.FilterAddException;

import org.gvsig.fmap.dal.coverage.grid.filter.BaseRasterFilter;

import org.gvsig.raster.impl.buffer.RasterBuffer;

import org.gvsig.raster.impl.store.ParamsImpl;

/**

 * Clase base para todos los filtros de contraste

 *

 * @author Miguel ?ngel Querol Carratal?  

 */

public class ContrastFilter extends BaseRasterFilter {

        public static String[]           names           = new String[] {"contrast"};

        /**

         * Variable que contendra el incremento del contraste.

         */

        int incrContraste = 0;

        /**

         * Constructor. Llama al constructor de la clase base y asigna el

         * nombre del filtro.

         */

        public ContrastFilter() {

                setName(names[0]);

        }

        public void pre() throws FilterAddException {

                super.pre();

                incrContraste = ((Integer) params.get("incrContraste")).intValue();

                createBufferResult(Buffer.TYPE_BYTE, raster.getBandCount());

        }

        public void post() {

                // En caso de que nadie apunte a raster, se liberar? su memoria.

                raster = null;

        }

        /**

         * Obtiene el incremento de contraster que se est? aplicando

         * @return entero que representa el incremento de contraste aplicado.

         */

        public int getContrastIncrease(){

                return this.incrContraste;

        }

        public String getGroup() {

                return "realces";

        }

        public Params getUIParams(String nameFilter) {

                Params params = new ParamsImpl();

                params.setParam("Contrast",

                                new Integer(incrContraste),

                                Params.SLIDER,

                                new String[]{ "-255", "255", "50", "1", "25" }); //min, max, valor defecto, intervalo peque?o, intervalo grande;

                return params;

        }

        public int getInRasterDataType() {

                //No parece que tenga sentido para im?genes que no sean RGB

                return RasterBuffer.TYPE_BYTE;

        }

        public int getOutRasterDataType() {

                return RasterBuffer.TYPE_BYTE;

        }

        public void process(int x, int y) {

        }

        /**

         * Algoritmo de contraste

         * @param px valor de la banda

         * @return valor de la banda con el algoritmo aplicado

         */

        protected int calcContrast(int px) {

                int result;

                int diferencia = 127 - px;

                if (incrContraste >= 0) {

                        result = (int) (px - (0.02 * diferencia * incrContraste)); // ((5.0 * 0.1) / 25) = 0.02

                } else {

                        result = (int) (px - (0.004 * diferencia * incrContraste)); // (0.1 / 25) = 0.004;

                        if (px < 127) {

                                if (result > 127) result = 127;

                        } else {

                                if (result < 127) result = 127;

                        }

                }

                if (result < 0)

                        result = 0;

                else {

                        if (result > 255)

                                result = 255;

                }

                return result;

        }

        public String[] getNames() {

                return names;

        }

}