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.segmentation;

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

import org.gvsig.raster.impl.datastruct.Kernel;

/**

 * Filtro de primera derivada que se aplica en la imagen. Toma como entrada la imagen y el

 * umbral (cero para no umbralizar).

 * 

 * @author Diego Guerrero Sevilla <diego.guerrero@uclm.es>

 */

public class FirstDerivativeFloatFilter extends FirstDerivativeFilter {

        public void process(int col, int line) {

                int out;

                int convoResult[] = new int[4];

                int ladoVentana = 3;

                int semiLado = (ladoVentana - 1) >> 1;

                double ventana[][] = new double[ladoVentana][ladoVentana];

                Kernel kernel = null;

                for (int band = 0; band < nBandsToProcess; band++) {

                        if ((col - semiLado >= 0) && (line - semiLado >= 0) && (col + semiLado < width) && (line + semiLado < height)) {

                                // Obtener el vector con la ventanas de muestras

                                for (int j = -semiLado; j <= semiLado; j++)

                                        for (int i = -semiLado; i <= semiLado; i++)

                                                ventana[i + semiLado][j + semiLado] = raster.getElemFloat(line + j, col + i, band);

                                kernel = new Kernel(ventana);

                                convoResult[0] = (int) operatorH.convolution(kernel);

                                convoResult[1] = (int) operatorV.convolution(kernel);

                                if (compare) {

                                        if (convoResult[0] > convoResult[1])

                                                out = convoResult[0];

                                        else

                                                out = convoResult[1];

                                } else {

                                        out = (int) Math.sqrt(Math.pow(convoResult[0], 2) + Math.pow(convoResult[1], 2));

                                }

                                if (umbral > 0) {

                                        if (out >= (255 - umbral))

                                                out = 255;

                                        else

                                                out = 0;

                                } else {

                                        if (out < 0)

                                                out = 0;

                                        else if (out > 255)

                                                out = 255;

                                }

                                rasterResult.setElem(line, col, band, (byte) out);

                        } else {

                                rasterResult.setElem(line, col, band, (byte) raster.getElemFloat(line, col, band));

                        }

                }

                if(hasTransparency)  

                        rasterResult.setElem(line, col, rasterResult.getBandCount() - 1, 

                                        raster.getElemFloat(line, col, raster.getBandCount() - 1));

        }

        public int getInRasterDataType() {

                return Buffer.TYPE_FLOAT;

        }

}