Capturing image from webcam in java?

Question

How can I continuously capture images from a webcam?

I want to experiment with object recognition (by maybe using java media framework).

I was thinking of creating two threads

one thread:

• Node 1: capture live image
• Node 2: save image as "1.jpg"
• Node 3: wait 5 seconds
• Node 4: repeat...

other thread:

• Node 1: wait until image is captured
• Node 2: using the "1.jpg" get colors from every pixle
• Node 3: save data in arrays
• Node 4: repeat...

Answer 1

This JavaCV implementation works fine.

Code:

import org.bytedeco.javacv.*;

import static org.bytedeco.javacpp.opencv_core.IplImage;
import static org.bytedeco.javacpp.opencv_core.cvFlip;
import static org.bytedeco.javacpp.opencv_imgcodecs.cvSaveImage;


/**
 * Created by gtiwari on 1/3/2017.
 */

public class Test implements Runnable {
    final int INTERVAL = 100;///you may use interval
    CanvasFrame canvas = new CanvasFrame("Web Cam");

    public Test() {
        canvas.setDefaultCloseOperation(javax.swing.JFrame.EXIT_ON_CLOSE);
    }

    public void run() {

        FrameGrabber grabber = new VideoInputFrameGrabber(0); // 1 for next camera
        OpenCVFrameConverter.ToIplImage converter = new OpenCVFrameConverter.ToIplImage();
        IplImage img;
        int i = 0;
        try {
            grabber.start();
            while (true) {
                Frame frame = grabber.grab();

                img = converter.convert(frame);

                //the grabbed frame will be flipped, re-flip to make it right
                cvFlip(img, img, 1);// l-r = 90_degrees_steps_anti_clockwise

                //save
                cvSaveImage((i++) + "-aa.jpg", img);

                canvas.showImage(converter.convert(img));

                Thread.sleep(INTERVAL);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public static void main(String[] args) {
        Test gs = new Test();
        Thread th = new Thread(gs);
        th.start();
    }
}

There is also post on configuration for JavaCV

You can modify the codes and be able to save the images in regular interval and do rest of the processing you want.

Answer 2

Try using JMyron How To Use Webcam Using Java. I think using JMyron is the easiest way to access a webcam using java. I tried to use it with a 64-bit processor, but it gave me an error. It worked just fine on a 32-bit processor, though.

Answer 3

Here is a similar question with some - yet unaccepted - answers. One of them mentions FMJ as a java alternative to JMF.

Answer 4

You can try Marvin Framework. It provides an interface to work with cameras. Moreover, it also provides a set of real-time video processing features, like object tracking and filtering.

Take a look!

Real-time Video Processing Demo:
http://www.youtube.com/watch?v=D5mBt0kRYvk

You can use the source below. Just save a frame using MarvinImageIO.saveImage() every 5 second.

Webcam video demo:

public class SimpleVideoTest extends JFrame implements Runnable{

    private MarvinVideoInterface    videoAdapter;
    private MarvinImage             image;
    private MarvinImagePanel        videoPanel;

    public SimpleVideoTest(){
        super("Simple Video Test");
        videoAdapter = new MarvinJavaCVAdapter();
        videoAdapter.connect(0);
        videoPanel = new MarvinImagePanel();
        add(videoPanel);
        new Thread(this).start();
        setSize(800,600);
        setVisible(true);
    }
    @Override
    public void run() {
        while(true){
            // Request a video frame and set into the VideoPanel
            image = videoAdapter.getFrame();
            videoPanel.setImage(image);
        }
    }
    public static void main(String[] args) {
        SimpleVideoTest t = new SimpleVideoTest();
        t.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
}

For those who just want to take a single picture:

WebcamPicture.java

public class WebcamPicture {
    public static void main(String[] args) {
        try{
            MarvinVideoInterface videoAdapter = new MarvinJavaCVAdapter();
            videoAdapter.connect(0);
            MarvinImage image = videoAdapter.getFrame();
            MarvinImageIO.saveImage(image, "./res/webcam_picture.jpg");
        } catch(MarvinVideoInterfaceException e){
            e.printStackTrace();
        }
    }
}