edu.stanford.rsl.conrad.segmentation.MultiChannelGridFeatureExtractor.java Source code

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Here is the source code for edu.stanford.rsl.conrad.segmentation.MultiChannelGridFeatureExtractor.java

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/*
 * Copyright (C) 2017 Andreas Maier
 * CONRAD is developed as an Open Source project under the GNU General Public License (GPL).
 */
package edu.stanford.rsl.conrad.segmentation;

import java.util.ArrayList;

import weka.core.Attribute;
import weka.core.Instances;
import weka.core.Utils;
import edu.stanford.rsl.conrad.data.numeric.Grid2D;
import edu.stanford.rsl.conrad.data.numeric.MultiChannelGrid2D;

public class MultiChannelGridFeatureExtractor extends GridFeatureExtractor {

    /**
     * 
     */
    private static final long serialVersionUID = -58855970888618830L;
    MultiChannelGrid2D multiChannelGrid;

    @Override
    public void prepareForSerialization() {
        super.prepareForSerialization();
        multiChannelGrid = null;
    }

    @Override
    public void setDataGrid(Grid2D dataGrid) {
        super.setDataGrid(dataGrid);
        multiChannelGrid = (MultiChannelGrid2D) dataGrid;
    }

    @Override
    public void configure() throws Exception {
        multiChannelGrid = (MultiChannelGrid2D) dataGrid;
        int numFeatures = multiChannelGrid.getNumberOfChannels();
        // attribs entspricht features
        attribs = new ArrayList<Attribute>(numFeatures + 1);
        for (int i = 0; i < numFeatures; i++) {
            String nameString = multiChannelGrid.getChannelNames()[i];
            attribs.add(new weka.core.Attribute(nameString));
        }
        Attribute classAttribute = generateClassAttribute();
        attribs.add(classAttribute);
        //leeres set von feature vectoren
        instances = new Instances(className, attribs, 0);
        instances.setClass(classAttribute);
        configured = true;
    }

    @Override
    public double[] extractFeatureAtIndex(int x, int y) {
        //array mit Werten der Features
        double attValues[] = new double[attribs.size()];

        attValues[attribs.size() - 1] = labelGrid.getPixelValue(x, y);
        //Channels entsprechen anzahl der verschiedenen bins
        int numFeatures = multiChannelGrid.getNumberOfChannels();
        //extrahiere feature fr jeden bin
        for (int c = 0; c < numFeatures; c++) {
            double value = multiChannelGrid.getChannel(c).getPixelValue(x, y);
            attValues[c] = value;
            if (Double.isInfinite(attValues[c])) {
                attValues[c] = Utils.missingValue();
            }

        }
        return attValues;
    }

    @Override
    public String getName() {
        return "Channels as Features";
    }
}