Scaler.java

package ij.plugin.filter;
import ij.*;
import ij.gui.*;
import ij.process.*;
import ij.measure.*;
import java.awt.*;

public class Scaler implements PlugInFilter {
    private ImagePlus imp;
    private static double xscale = 0.5;
    private static double yscale = 0.5;
    private static boolean interpolate = true;

    public int setup(String arg, ImagePlus imp) {
        this.imp = imp;
        IJ.register(Scaler.class);
        if (imp!=null) {
            Roi roi = imp.getRoi();
            if (roi!=null && !roi.isArea())
                imp.killRoi(); // ignore any line selection
        }
        return DOES_ALL;
    }

    public void run(ImageProcessor ip) {
        if (!showDialog())
            return;
        ip.setInterpolate(interpolate);
        imp.startTiming();
        try {
            scale(ip);
        }
        catch(OutOfMemoryError o) {
            IJ.outOfMemory("Scale");
        }
        IJ.showProgress(1.0);
    }
    
    void scale(ImageProcessor ip) {
        ip.scale(xscale, yscale);
        imp.killRoi();
    }
    
    boolean showDialog() {
        GenericDialog gd = new GenericDialog("Scale");
        gd.addNumericField("X Scale (0.05-25):", xscale, 2);
        gd.addNumericField("Y Scale (0.05-25):", yscale, 2);
        gd.addCheckbox("Interpolate", interpolate);
        gd.showDialog();

        if (gd.wasCanceled())
            return false;
        xscale = gd.getNextNumber();
        yscale = gd.getNextNumber();
        if (gd.invalidNumber()) {
            IJ.error("X or Y scale are invalid.");
            return false;
        }
        if (xscale > 25.0) xscale = 25.0;
        if (xscale < 0.05) xscale = 0.05;
        if (yscale > 25.0) yscale = 25.0;
        if (yscale < 0.05) yscale = 0.05;
        interpolate = gd.getNextBoolean();
        return true;
    }

}