Viewing and storing images from an IP Camera

If you’ve recently purchased an IP camera and want to programmatically retrieve and store images using Java, this post is for you. Recently I bought a couple of IP Cameras for testing purposes. I noticed that each IP camera has different surveillance tools and web interfaces. But most of these IP cameras have in common that they provide a static image URL that you can access directly via your browser. Leveraging this feature, you can build a simple Java application to grab and store those images.

In this post, I'll show you how to see that image and store it using a very simple Java application. For this demonstration, I’ll be using a LinkSys WVC200 "Wireless PTZ Internet Camera with Audio". This camera was the most affordable option I found with decent features at the time of purchase.

This camera includes a functional web interface. However, for visualization, you’re tied to a Windows desktop since it relies on an ActiveX control to display and control the image. Thankfully, LinkSys provides the camera’s firmware source code, which gives helpful insights, including the URL to access the static image.

If you analyze the source code you can find some hints to get the URL where the static image is served (there's an URL for ASF video format too, with some time you can develop an app to store and play the video). For this camera, the URL is http://CAMERAIP/img/snapshot.cgi?size=640x480.

With this information, we can create a simple Java application to grab and store the image. If you have a different type of camera, you can adapt the program by specifying the URL for that camera.

public class IPCameraImageFetcher {
  public static void main(String[] args) {
    try {
      // Build a new URL specifying the path to where the image is served
      URL url = new URL ( "http://192.168.10.80/img/snapshot.cgi?size=640x480");
      // String with the user and password to access the camera interface
      // (userName and password that you would enter in the browser
      String userPassword = "USER:PASSWORD";
      // We must encode with Base64 to supply it with the header.
      String encoding = new Base64Encoder(userPassword).processString();
      // Open the connection
      URLConnection uc = url.openConnection();
      // Specify the authorization
      uc.setRequestProperty ("Authorization", "Basic " + encoding);
      // Load a copy of the image into memory
      BufferedImage img = ImageIO.read(uc.getInputStream());
      // Store the image in the specified path
      ImageIO.write(img, "jpg", new File("pathToFile"));
    } catch (MalformedURLException ex) {
      ex.printStackTrace();
    } catch (IOException ex) {
      ex.printStackTrace();
    }
  }
}

With just a few lines of code, you can extend this application's functionality to create a robust surveillance application or tool. Many commercial surveillance systems share the same basic functionality as the 10 lines of code above, despite their higher price tags. With some effort, you could even add features like periodic image capture, video archiving, or advanced controls.