package nl.captcha.noise;
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.geom.CubicCurve2D;
import java.awt.geom.PathIterator;
import java.awt.geom.Point2D;
import java.awt.image.BufferedImage;
import java.security.SecureRandom;
import java.util.Random;
/**
* Adds a randomly curved line to the image.
*
* @author <a href="mailto:james.childers@gmail.com">James Childers</a>
*
*/
public class CurvedLineNoiseProducer implements NoiseProducer {
private static final Random RAND = new SecureRandom();
private final Color _color;
private final float _width;
public CurvedLineNoiseProducer() {
this(Color.BLACK, 3.0f);
}
public CurvedLineNoiseProducer(Color color, float width) {
_color = color;
_width = width;
}
public void makeNoise(BufferedImage image) {
int width = image.getWidth();
int height = image.getHeight();
// the curve from where the points are taken
CubicCurve2D cc = new CubicCurve2D.Float(width * .1f, height
* RAND.nextFloat(), width * .1f, height
* RAND.nextFloat(), width * .25f, height
* RAND.nextFloat(), width * .9f, height
* RAND.nextFloat());
// creates an iterator to define the boundary of the flattened curve
PathIterator pi = cc.getPathIterator(null, 2);
Point2D tmp[] = new Point2D[200];
int i = 0;
// while pi is iterating the curve, adds points to tmp array
while (!pi.isDone()) {
float[] coords = new float[6];
switch (pi.currentSegment(coords)) {
case PathIterator.SEG_MOVETO:
case PathIterator.SEG_LINETO:
tmp[i] = new Point2D.Float(coords[0], coords[1]);
}
i++;
pi.next();
}
// the points where the line changes the stroke and direction
Point2D[] pts = new Point2D[i];
// copies points from tmp to pts
System.arraycopy(tmp, 0, pts, 0, i);
Graphics2D graph = (Graphics2D) image.getGraphics();
graph.setRenderingHints(new RenderingHints(
RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON));
graph.setColor(_color);
// for the maximum 3 point change the stroke and direction
for (i = 0; i < pts.length - 1; i++) {
if (i < 3) {
graph.setStroke(new BasicStroke(_width));
}
graph.drawLine((int) pts[i].getX(), (int) pts[i].getY(),
(int) pts[i + 1].getX(), (int) pts[i + 1].getY());
}
graph.dispose();
}
}