jaitools.demo.vectorize.VectorizeDemo Maven / Gradle / Ivy
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/*
* Copyright 2010-2011 Michael Bedward
*
* This file is part of jai-tools.
*
* jai-tools is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* jai-tools is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with jai-tools. If not, see
* The code has examples of the different parameters that can be used to vectorize
* a subset of the source image by bounds (using an ROI) or by pixel value.
*
* @author Michael Bedward
* @since 1.1
* @version $Id: VectorizeDemo.java 1386 2011-02-11 03:47:53Z michael.bedward $
*/
public class VectorizeDemo {
/**
* Run the demo application.
* @param args ignored
*/
public static void main(String[] args) {
VectorizeDemo me = new VectorizeDemo();
me.demo();
}
/**
* Run the Vectorize operation on a source image with a chessboard pattern
* where the chessboard squares have value 1 or 0.
*/
private void demo() {
final int JAI_TILE_WIDTH = 128;
final int IMAGE_WIDTH = 240;
final int SQUARE_WIDTH = 30;
JAI.setDefaultTileSize(new Dimension(JAI_TILE_WIDTH, JAI_TILE_WIDTH));
TiledImage src = ImageUtils.createConstantImage(IMAGE_WIDTH, IMAGE_WIDTH, 0);
Map args = new HashMap();
/**
* Create a chessboard pattern
*/
for (int y = 0; y < IMAGE_WIDTH; y++) {
int ysquare = y / SQUARE_WIDTH;
for (int x = 0; x < IMAGE_WIDTH; x++) {
int xsquare = x / SQUARE_WIDTH;
if (xsquare % 2 == ysquare % 2) src.setSample(x, y, 0, 1);
}
}
System.out.println("Source image is a chessboard pattern.");
System.out.printf("Image bounds: %d x %d \n", IMAGE_WIDTH, IMAGE_WIDTH);
System.out.printf("Chessboard squares: %d x %d \n", SQUARE_WIDTH, SQUARE_WIDTH);
System.out.println("Vectorizing:");
System.out.println("With default arguments...");
Collection polys = doVectorize(src, args);
printPolys(polys, 5);
System.out.println("With 0 as an outside value...");
args.put("outsideValues", Collections.singleton(0));
polys = doVectorize(src, args);
printPolys(polys, 5);
System.out.println("With insideEdges arg set to false...");
args.clear();
args.put("insideEdges", Boolean.FALSE);
polys = doVectorize(src, args);
printPolys(polys, 1);
System.out.println("With an ROI over central 4x4 chessboard squares...");
args.clear();
ROI roi = new ROIShape(
new Rectangle(2*SQUARE_WIDTH, 2*SQUARE_WIDTH, 4*SQUARE_WIDTH, 4*SQUARE_WIDTH));
args.put("roi", roi);
polys = doVectorize(src, args);
printPolys(polys, 5);
}
/**
* Helper function to run the Vectorize operation with given parameters and
* retrieve the vectors.
*
* @param src the source image
* @param args a {@code Map} of parameter names and values
*
* @return the generated vectors as JTS Polygons
*/
private Collection doVectorize(RenderedImage src, Map args) {
ParameterBlockJAI pb = new ParameterBlockJAI("Vectorize");
pb.setSource("source0", src);
// Set any parameters that were passed in
for (Entry e : args.entrySet()) {
pb.setParameter(e.getKey(), e.getValue());
}
// Get the desintation image: this is the unmodified source image data
// plus a property for the generated vectors
RenderedOp dest = JAI.create("Vectorize", pb);
// Get the vectors
Object property = dest.getProperty(VectorizeDescriptor.VECTOR_PROPERTY_NAME);
return (Collection) property;
}
/**
* Print a summary of the polygons
*
* @param polys the polygons
* @param nlist the number to print as Well Known Text (WKT) string
*/
private void printPolys(Collection polys, int nlist) {
int n = polys.size();
System.out.printf(" Got %d polygon%s \n", n, (n == 1 ? "" : "s"));
nlist = Math.min(nlist, polys.size());
if (nlist > 0) {
Iterator iter = polys.iterator();
int k = 0;
while (k < nlist) {
Polygon p = iter.next();
p.normalize();
// print the polygon as a WKT string
System.out.println(" " + p.toText());
// get the value of the source image region bounded by this polygon
// (this is stored as "user data" in the Polygon object)
System.out.println(" Image value: " + p.getUserData());
k++ ;
}
if (k < polys.size()) System.out.println(" ...");
System.out.println();
}
}
}