Application: gvSIG desktop » gvSIG tools: ToolBox

package es.unex.sextante.gridCategorical.filterClumps;

import java.awt.Point;

import java.util.ArrayList;

import es.unex.sextante.additionalInfo.AdditionalInfoNumericalValue;

import es.unex.sextante.core.GeoAlgorithm;

import es.unex.sextante.core.Sextante;

import es.unex.sextante.dataObjects.IRasterLayer;

import es.unex.sextante.exceptions.GeoAlgorithmExecutionException;

import es.unex.sextante.exceptions.RepeatedParameterNameException;

public class FilterClumpsAlgorithm

         extends

            GeoAlgorithm {

   private final static int   m_iOffsetX[] = { 0, 1, 1, 1, 0, -1, -1, -1 };

   private final static int   m_iOffsetY[] = { 1, 1, 0, -1, -1, -1, 0, 1 };

   public static final String INPUT        = "INPUT";

   public static final String MINAREA      = "MINAREA";

   public static final String RESULT       = "RESULT";

   int                        m_iArea;

   int                        m_iNX, m_iNY;

   IRasterLayer               m_Grid;

   IRasterLayer               m_Result;

   boolean                    m_IsCellAlreadyVisited[][];

   boolean                    m_IsCellAlreadyVisitedArea[][];

   @Override

   public void defineCharacteristics() {

      setName(Sextante.getText("Filter_clumps"));

      setGroup(Sextante.getText("Raster_categories_analysis"));

      setUserCanDefineAnalysisExtent(true);

      try {

         m_Parameters.addInputRasterLayer(INPUT, Sextante.getText("Layer"), true);

         m_Parameters.addNumericalValue(MINAREA, Sextante.getText("Min_area_[cells]"),

                  AdditionalInfoNumericalValue.NUMERICAL_VALUE_INTEGER, 100, 1, Integer.MAX_VALUE);

         addOutputRasterLayer(RESULT, Sextante.getText("Filtered_layer"));

      }

      catch (final RepeatedParameterNameException e) {

         Sextante.addErrorToLog(e);

      }

   }

   @Override

   public boolean processAlgorithm() throws GeoAlgorithmExecutionException {

      int x, y;

      m_Grid = m_Parameters.getParameterValueAsRasterLayer(INPUT);

      m_iArea = m_Parameters.getParameterValueAsInt(MINAREA);

      m_Result = getNewRasterLayer(RESULT, m_Grid.getName() + "[filt]", IRasterLayer.RASTER_DATA_TYPE_INT);

      m_Grid.setWindowExtent(m_Result);

      m_Grid.setInterpolationMethod(IRasterLayer.INTERPOLATION_NearestNeighbour);

      m_iNX = m_Grid.getNX();

      m_iNY = m_Grid.getNY();

      m_IsCellAlreadyVisited = new boolean[m_iNX][m_iNY];

      m_IsCellAlreadyVisitedArea = new boolean[m_iNX][m_iNY];

      m_Result.assign(m_Grid);

      for (y = 0; (y < m_iNY) && setProgress(y, m_iNY); y++) {

         for (x = 0; x < m_iNX; x++) {

            if (!m_IsCellAlreadyVisited[x][y]) {

               int iArea = getArea(x, y);

               if (iArea < m_iArea) {

                  setToNoData(x, y);

               }

               else {

                  iArea = iArea + 1;

               }

            }

         }

      }

      return !m_Task.isCanceled();

   }

   private int getArea(int x,

                       int y) {

      int x2, y2;

      int iInitClass;

      int iPt;

      int n;

      int iClass;

      int iArea = 1;

      ArrayList centralPoints = new ArrayList();

      ArrayList adjPoints = new ArrayList();

      Point point;

      if (m_IsCellAlreadyVisitedArea[x][y]) {

         return Integer.MAX_VALUE;

      }

      iInitClass = m_Grid.getCellValueAsInt(x, y);

      centralPoints.add(new Point(x, y));

      m_IsCellAlreadyVisitedArea[x][y] = true;

      while (centralPoints.size() != 0) {

         for (iPt = 0; iPt < centralPoints.size(); iPt++) {

            point = (Point) centralPoints.get(iPt);

            x = point.x;

            y = point.y;

            iClass = m_Grid.getCellValueAsInt(x, y);

            if (!m_Grid.isNoDataValue(iClass)) {

               for (n = 0; n < 8; n++) {

                  x2 = x + m_iOffsetX[n];

                  y2 = y + m_iOffsetY[n];

                  iClass = m_Grid.getCellValueAsInt(x2, y2);

                  if (!m_Grid.isNoDataValue(iClass)) {

                     if (m_IsCellAlreadyVisitedArea[x2][y2] == false) {

                        if (iInitClass == iClass) {

                           m_IsCellAlreadyVisitedArea[x2][y2] = true;

                           adjPoints.add(new Point(x2, y2));

                           iArea += 1;

                        }

                     }

                  }

               }

            }

         }

         centralPoints = adjPoints;

         adjPoints = new ArrayList();

         if (m_Task.isCanceled()) {

            return Integer.MAX_VALUE;

         }

      }

      return iArea;

   }

   private void setToNoData(int x,

                            int y) {

      int x2, y2;

      int iInitClass;

      int iPt;

      int n;

      int iClass;

      ArrayList centralPoints = new ArrayList();

      ArrayList adjPoints = new ArrayList();

      Point point;

      iInitClass = m_Result.getCellValueAsInt(x, y);

      centralPoints.add(new Point(x, y));

      while (centralPoints.size() != 0) {

         for (iPt = 0; iPt < centralPoints.size(); iPt++) {

            point = (Point) centralPoints.get(iPt);

            x = point.x;

            y = point.y;

            iClass = m_Result.getCellValueAsInt(x, y);

            if (!m_Result.isNoDataValue(iClass)) {

               m_Result.setNoData(x, y);

               for (n = 0; n < 8; n++) {

                  x2 = x + m_iOffsetX[n];

                  y2 = y + m_iOffsetY[n];

                  iClass = m_Result.getCellValueAsInt(x2, y2);

                  if (!m_Result.isNoDataValue(iClass)) {

                     if (iInitClass == iClass) {

                        adjPoints.add(new Point(x2, y2));

                     }

                  }

               }

            }

         }

         centralPoints = adjPoints;

         adjPoints = new ArrayList();

         if (m_Task.isCanceled()) {

            return;

         }

      }

   }

}