Build status for all platforms: 
Commercial support:
This directory contains the JavaCPP Presets module for:
- Chilitags http://chili.epfl.ch/software
Please refer to the parent README.md file for more detailed information about the JavaCPP Presets.
Java API documentation is available here:
Here is the live detection sample of Chilitags ported to Java from this C++ source file:
We can use Maven 3 to download and install automatically all the class files as well as the native binaries. To run this sample code, after creating the pom.xml and DetectLive.java source files below, simply execute on the command line:
$ mvn compile exec:java -Dexec.args="[xRes] [yRes] [cameraIndex]"<project>
<modelVersion>4.0.0</modelVersion>
<groupId>org.bytedeco.chilitags</groupId>
<artifactId>detectlive</artifactId>
<version>1.5.8</version>
<properties>
<exec.mainClass>DetectLive</exec.mainClass>
</properties>
<dependencies>
<dependency>
<groupId>org.bytedeco</groupId>
<artifactId>chilitags-platform</artifactId>
<version>master-1.5.8</version>
</dependency>
</dependencies>
<build>
<sourceDirectory>.</sourceDirectory>
</build>
</project>/*******************************************************************************
* Copyright 2013-2014 EPFL *
* Copyright 2013-2014 Quentin Bonnard *
* *
* This file is part of chilitags. *
* *
* Chilitags is free software: you can redistribute it and/or modify *
* it under the terms of the Lesser GNU General Public License as *
* published by the Free Software Foundation, either version 3 of the *
* License, or (at your option) any later version. *
* *
* Chilitags 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 Chilitags. If not, see <http://www.gnu.org/licenses/>. *
*******************************************************************************/
// This file serves as an illustration of how to use Chilitags
import org.bytedeco.javacpp.*;
import org.bytedeco.javacpp.indexer.*;
// The Chilitags header
import org.bytedeco.chilitags.*;
import static org.bytedeco.chilitags.global.chilitags.*;
import org.bytedeco.opencv.opencv_imgproc.*;
import static org.bytedeco.opencv.global.opencv_imgproc.*; // getTickCount...
import org.bytedeco.opencv.opencv_core.*;
import static org.bytedeco.opencv.global.opencv_core.*; // CV_AA
// OpenCV goodness for I/O
import org.bytedeco.opencv.opencv_highgui.*;
import org.bytedeco.opencv.opencv_videoio.*;
import static org.bytedeco.opencv.global.opencv_highgui.*;
import static org.bytedeco.opencv.global.opencv_videoio.*;
public class DetectLive {
public static void main(String[] args) {
// Simple parsing of the parameters related to the image acquisition
int xRes = 640;
int yRes = 480;
int cameraIndex = 0;
if (args.length > 1) {
xRes = Integer.parseInt(args[0]);
yRes = Integer.parseInt(args[1]);
}
if (args.length > 2) {
cameraIndex = Integer.parseInt(args[2]);
}
// The source of input images
VideoCapture capture = new VideoCapture(cameraIndex);
if (!capture.isOpened()) {
System.err.println("Unable to initialise video capture.");
System.exit(1);
}
capture.set(CAP_PROP_FRAME_WIDTH, xRes);
capture.set(CAP_PROP_FRAME_HEIGHT, yRes);
Mat inputImage = new Mat();
// The tag detection happens in the Chilitags class.
Chilitags chilitags = new Chilitags();
// The detection is not perfect, so if a tag is not detected during one frame,
// the tag will shortly disappears, which results in flickering.
// To address this, Chilitags "cheats" by keeping tags for n frames
// at the same position. When tags disappear for more than 5 frames,
// Chilitags actually removes it.
// Here, we cancel this to show the raw detection results.
chilitags.setFilter(0, 0.0f);
namedWindow("DisplayChilitags");
// Main loop, exiting when 'q is pressed'
while ('q' != (char)waitKey(1)) {
// Capture a new image.
capture.read(inputImage);
// Start measuring the time needed for the detection
long startTime = getTickCount();
// Detect tags on the current image (and time the detection);
// The resulting map associates tag ids (between 0 and 1023)
// to four 2D points corresponding to the corners positions
// in the picture.
TagCornerMap tags = chilitags.find(inputImage);
// Measure the processing time needed for the detection
long endTime = getTickCount();
float processingTime = 1000.0f * ((float)endTime - startTime) / (float)getTickFrequency();
// Now we start using the result of the detection.
// First, we set up some constants related to the information overlaid
// on the captured image
final Scalar COLOR = new Scalar(255, 0, 255, 0);
// OpenCv can draw with sub-pixel precision with fixed point coordinates
final int SHIFT = 16;
final float PRECISION = 1 << SHIFT;
// We dont want to draw directly on the input image, so we clone it
Mat outputImage = inputImage.clone();
for (TagCornerMap.Iterator tag = tags.begin(); !tag.equals(tags.end()); tag = tag.increment()) {
int id = tag.first();
// We wrap the corner matrix into a datastructure that allows an
// easy access to the coordinates
FloatIndexer corners = FloatIndexer.create(tag.second().capacity(8), new long[] { 4 }, new long[] { 2 });
// We start by drawing the borders of the tag
for (int i = 0; i < 4; i++) {
line(outputImage,
new Point(Math.round(PRECISION*corners.get(i, 0)), Math.round(PRECISION*corners.get(i, 1))),
new Point(Math.round(PRECISION*corners.get((i+1)%4, 0)), Math.round(PRECISION*corners.get((i+1)%4, 1))),
COLOR, 1, LINE_AA, SHIFT);
}
// Other points can be computed from the four corners of the Quad.
// Chilitags are oriented. It means that the points 0,1,2,3 of
// the Quad coordinates are consistently the top-left, top-right,
// bottom-right and bottom-left corners.
// (i.e. clockwise, starting from top-left)
// Using this, we can compute (an approximation of) the center of
// tag.
Point center = new Point(Math.round(0.5f*(corners.get(0, 0) + corners.get(2, 0))),
Math.round(0.5f*(corners.get(0, 1) + corners.get(2, 1))));
putText(outputImage, String.format("%d", id), center,
FONT_HERSHEY_SIMPLEX, 0.5f, COLOR);
}
// Some stats on the current frame (resolution and processing time)
putText(outputImage,
String.format("%dx%d %4.0f ms (press q to quit)",
outputImage.cols(), outputImage.rows(),
processingTime),
new Point(32,32),
FONT_HERSHEY_SIMPLEX, 0.5f, COLOR);
// Finally...
imshow("DisplayChilitags", outputImage);
}
destroyWindow("DisplayChilitags");
capture.release();
}
}