Application: gvSIG desktop » gvSIG tools: ToolBox

package es.unex.sextante.vegetationIndices.base;

import es.unex.sextante.core.GeoAlgorithm;

import es.unex.sextante.core.AnalysisExtent;

import es.unex.sextante.core.Sextante;

import es.unex.sextante.dataObjects.IRasterLayer;

import es.unex.sextante.exceptions.GeoAlgorithmExecutionException;

import es.unex.sextante.exceptions.OptionalParentParameterException;

import es.unex.sextante.exceptions.RepeatedParameterNameException;

import es.unex.sextante.exceptions.UndefinedParentParameterNameException;

public abstract class SlopeBasedAlgorithm

         extends

            GeoAlgorithm {

   public static final String LAYERRED = "LAYERRED";

   public static final String BANDRED  = "BANDRED";

   public static final String BANDNIR  = "BANDNIR";

   public static final String LAYERNIR = "LAYERNIR";

   public static final String RESULT   = "RESULT";

   private IRasterLayer       m_LayerRed, m_LayerNIR;

   protected double           m_dNoData;

   @Override

   public void defineCharacteristics() {

      setUserCanDefineAnalysisExtent(true);

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

      this.setGroup(Sextante.getText("Vegetation_indices"));

      try {

         m_Parameters.addInputRasterLayer(LAYERRED, Sextante.getText("Red_layer"), true);

         m_Parameters.addBand(BANDRED, Sextante.getText("Red_band"), LAYERRED);

         m_Parameters.addInputRasterLayer(LAYERNIR, Sextante.getText("Near_infrared_layer"), true);

         m_Parameters.addBand(BANDNIR, Sextante.getText("Near_infrared_band"), LAYERNIR);

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

      }

      catch (final RepeatedParameterNameException e) {

         Sextante.addErrorToLog(e);

      }

      catch (final UndefinedParentParameterNameException e) {

         Sextante.addErrorToLog(e);

      }

      catch (final OptionalParentParameterException e) {

         Sextante.addErrorToLog(e);

      }

   }

   @Override

   public boolean processAlgorithm() throws GeoAlgorithmExecutionException {

      int x, y;

      int iNX, iNY;

      double dRed;

      double dNIR;

      double dIndex;

      AnalysisExtent extent;

      m_LayerRed = m_Parameters.getParameterValueAsRasterLayer(LAYERRED);

      final int iBandRed = m_Parameters.getParameterValueAsInt(BANDRED);

      m_LayerNIR = m_Parameters.getParameterValueAsRasterLayer(LAYERNIR);

      final int iBandNIR = m_Parameters.getParameterValueAsInt(BANDNIR);

      final IRasterLayer result = getNewRasterLayer(RESULT, getName(), IRasterLayer.RASTER_DATA_TYPE_DOUBLE);

      extent = result.getWindowGridExtent();

      m_LayerRed.setWindowExtent(extent);

      m_LayerNIR.setWindowExtent(extent);

      m_LayerRed.setInterpolationMethod(IRasterLayer.INTERPOLATION_NearestNeighbour);

      m_LayerNIR.setInterpolationMethod(IRasterLayer.INTERPOLATION_NearestNeighbour);

      iNX = m_LayerRed.getNX();

      iNY = m_LayerRed.getNY();

      m_dNoData = result.getNoDataValue();

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

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

            dRed = m_LayerRed.getCellValueAsDouble(x, y, iBandRed);

            dNIR = m_LayerNIR.getCellValueAsDouble(x, y, iBandNIR);

            if (!m_LayerRed.isNoDataValue(dRed) && !m_LayerNIR.isNoDataValue(dNIR)) {

               dIndex = getIndex(dRed, dNIR);

               result.setCellValue(x, y, dIndex);

            }

            else {

               result.setNoData(x, y);

            }

         }

      }

      return !m_Task.isCanceled();

   }

   protected double getNDVI(final double dRed,

                            final double dNIR) {

      return (dNIR - dRed) / (dNIR + dRed);

   }

   protected abstract double getIndex(double dRed,

                                      double dNIR);

}