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:
other thread:
This JavaCV implementation works fine.
Code:
import org.bytedeco.javacv.*;
import org.bytedeco.opencv.opencv_core.IplImage;
import java.io.File;
import static org.bytedeco.opencv.global.opencv_core.cvFlip;
import static org.bytedeco.opencv.helper.opencv_imgcodecs.cvSaveImage;
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() {
new File("images").mkdir();
FrameGrabber grabber = new OpenCVFrameGrabber(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("images" + File.separator + (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 code and be able to save the images in regular interval and do rest of the processing you want.
Some time ago I've created generic Java library which can be used to take pictures with a PC webcam. The API is very simple, not overfeatured, can work standalone, but also supports additional webcam drivers like OpenIMAJ, JMF, FMJ, LTI-CIVIL, etc, and some IP cameras.
Link to the project is https://github.com/sarxos/webcam-capture
Example code (take picture and save in test.jpg):
Webcam webcam = Webcam.getDefault();
webcam.open();
BufferedImage image = webcam.getImage();
ImageIO.write(image, "JPG", new File("test.jpg"));
It is also available in Maven Central Repository or as a separate ZIP which includes all required dependencies and 3rd party JARs.
JMyron is very simple for use. http://webcamxtra.sourceforge.net/
myron = new JMyron();
myron.start(imgw, imgh);
myron.update();
int[] img = myron.image();
This kind of goes off of gt_ebuddy's answer using JavaCV, but my video output is at a much higher quality then his answer. I've also added some other random improvements (such as closing down the program when ESC and CTRL+C are pressed, and making sure to close down the resources the program uses properly).
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.image.BufferedImage;
import javax.swing.AbstractAction;
import javax.swing.ActionMap;
import javax.swing.InputMap;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.KeyStroke;
import com.googlecode.javacv.CanvasFrame;
import com.googlecode.javacv.OpenCVFrameGrabber;
import com.googlecode.javacv.cpp.opencv_core.IplImage;
public class HighRes extends JComponent implements Runnable {
private static final long serialVersionUID = 1L;
private static CanvasFrame frame = new CanvasFrame("Web Cam");
private static boolean running = false;
private static int frameWidth = 800;
private static int frameHeight = 600;
private static OpenCVFrameGrabber grabber = new OpenCVFrameGrabber(0);
private static BufferedImage bufImg;
public HighRes()
{
// setup key bindings
ActionMap actionMap = frame.getRootPane().getActionMap();
InputMap inputMap = frame.getRootPane().getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW);
for (Keys direction : Keys.values())
{
actionMap.put(direction.getText(), new KeyBinding(direction.getText()));
inputMap.put(direction.getKeyStroke(), direction.getText());
}
frame.getRootPane().setActionMap(actionMap);
frame.getRootPane().setInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW, inputMap);
// setup window listener for close action
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
stop();
}
});
}
public static void main(String... args)
{
HighRes webcam = new HighRes();
webcam.start();
}
@Override
public void run()
{
try
{
grabber.setImageWidth(frameWidth);
grabber.setImageHeight(frameHeight);
grabber.start();
while (running)
{
final IplImage cvimg = grabber.grab();
if (cvimg != null)
{
// cvFlip(cvimg, cvimg, 1); // mirror
// show image on window
bufImg = cvimg.getBufferedImage();
frame.showImage(bufImg);
}
}
grabber.stop();
grabber.release();
frame.dispose();
}
catch (Exception e)
{
e.printStackTrace();
}
}
public void start()
{
new Thread(this).start();
running = true;
}
public void stop()
{
running = false;
}
private class KeyBinding extends AbstractAction {
private static final long serialVersionUID = 1L;
public KeyBinding(String text)
{
super(text);
putValue(ACTION_COMMAND_KEY, text);
}
@Override
public void actionPerformed(ActionEvent e)
{
String action = e.getActionCommand();
if (action.equals(Keys.ESCAPE.toString()) || action.equals(Keys.CTRLC.toString())) stop();
else System.out.println("Key Binding: " + action);
}
}
}
enum Keys
{
ESCAPE("Escape", KeyStroke.getKeyStroke(KeyEvent.VK_ESCAPE, 0)),
CTRLC("Control-C", KeyStroke.getKeyStroke(KeyEvent.VK_C, KeyEvent.CTRL_DOWN_MASK)),
UP("Up", KeyStroke.getKeyStroke(KeyEvent.VK_UP, 0)),
DOWN("Down", KeyStroke.getKeyStroke(KeyEvent.VK_DOWN, 0)),
LEFT("Left", KeyStroke.getKeyStroke(KeyEvent.VK_LEFT, 0)),
RIGHT("Right", KeyStroke.getKeyStroke(KeyEvent.VK_RIGHT, 0));
private String text;
private KeyStroke keyStroke;
Keys(String text, KeyStroke keyStroke)
{
this.text = text;
this.keyStroke = keyStroke;
}
public String getText()
{
return text;
}
public KeyStroke getKeyStroke()
{
return keyStroke;
}
@Override
public String toString()
{
return text;
}
}
You can try Java Webcam SDK library also. SDK demo applet is available at link.
I have used JMF on a videoconference application and it worked well on two laptops: one with integrated webcam and another with an old USB webcam. It requires JMF being installed and configured before-hand, but once you're done you can access the hardware via Java code fairly easily.
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();
}
}
}
I used Webcam Capture API. You can download it from here
webcam = Webcam.getDefault();
webcam.open();
if (webcam.isOpen()) { //if web cam open
BufferedImage image = webcam.getImage();
JLabel imageLbl = new JLabel();
imageLbl.setSize(640, 480); //show captured image
imageLbl.setIcon(new ImageIcon(image));
int showConfirmDialog = JOptionPane.showConfirmDialog(null, imageLbl, "Image Viewer", JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE, new ImageIcon(""));
if (showConfirmDialog == JOptionPane.YES_OPTION) {
JFileChooser chooser = new JFileChooser();
chooser.setDialogTitle("Save Image");
chooser.setFileFilter(new FileNameExtensionFilter("IMAGES ONLY", "png", "jpeg", "jpg")); //this file extentions are shown
int showSaveDialog = chooser.showSaveDialog(this);
if (showSaveDialog == 0) { //if pressed 'Save' button
String filePath = chooser.getCurrentDirectory().toString().replace("\\", "/");
String fileName = chooser.getSelectedFile().getName(); //get user entered file name to save
ImageIO.write(image, "PNG", new File(filePath + "/" + fileName + ".png"));
}
}
}
http://grack.com/downloads/school/enel619.10/report/java_media_framework.html
Using the Player with Swing
The Player can be easily used in a Swing application as well. The following code creates a Swing-based TV capture program with the video output displayed in the entire window:
import javax.media.*;
import javax.swing.*;
import java.awt.*;
import java.net.*;
import java.awt.event.*;
import javax.swing.event.*;
public class JMFTest extends JFrame {
Player _player;
JMFTest() {
addWindowListener( new WindowAdapter() {
public void windowClosing( WindowEvent e ) {
_player.stop();
_player.deallocate();
_player.close();
System.exit( 0 );
}
});
setExtent( 0, 0, 320, 260 );
JPanel panel = (JPanel)getContentPane();
panel.setLayout( new BorderLayout() );
String mediaFile = "vfw://1";
try {
MediaLocator mlr = new MediaLocator( mediaFile );
_player = Manager.createRealizedPlayer( mlr );
if (_player.getVisualComponent() != null)
panel.add("Center", _player.getVisualComponent());
if (_player.getControlPanelComponent() != null)
panel.add("South", _player.getControlPanelComponent());
}
catch (Exception e) {
System.err.println( "Got exception " + e );
}
}
public static void main(String[] args) {
JMFTest jmfTest = new JMFTest();
jmfTest.show();
}
}
Java usually doesn't like accessing hardware, so you will need a driver program of some sort, as goldenmean said. I've done this on my laptop by finding a command line program that snaps a picture. Then it's the same as goldenmean explained; you run the command line program from your java program in the takepicture() routine, and the rest of your code runs the same.
Except for the part about reading pixel values into an array, you might be better served by saving the file to BMP, which is nearly that format already, then using the standard java image libraries on it.
Using a command line program adds a dependency to your program and makes it less portable, but so was the webcam, right?
I believe the web-cam application software which comes along with the web-cam, or you native windows webcam software can be run in a batch script(windows/dos script) after turning the web cam on(i.e. if it needs an external power supply). In the bacth script , u can add appropriate delay to capture after certain time period. And keep executing the capture command in loop.
I guess this should be possible
-AD
There's a pretty nice interface for this in processing, which is kind of a pidgin java designed for graphics. It gets used in some image recognition work, such as that link.
Depending on what you need out of it, you might be able to load the video library that's used there in java, or if you're just playing around with it you might be able to get by using processing itself.
FMJ can do this, as can the supporting library it uses, LTI-CIVIL. Both are on sourceforge.
Recommand using FMJ for multimedia relatived java app.
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.
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