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Preston_5564C06.fm Page 173 Friday, September 23, 2005 5:13 AM

CHAPTER 6 ■ VISION 173

// in case this is overloaded later
imagePanel.setImage(currentImage);

}

public static void main(String[] args) {
try {
ImageViewer imageViewer = new ImageViewer("sample_images/stonehenge.jpg");
} catch (Exception e) {
e.printStackTrace();
System.exit(1);
}
}
}

These are the basics. Now it’s time to view images captured from a webcam. In the next
section, I’ll show you how to configure the Java Media Framework, use that to get the image
from your webcam inside the ImageViewer, and then create a class for viewing the webcam
image in real time.
So far, the classes created were
• WindowUtilities: Makes it easier to create a native look and feel for your Swing components

• ExitListener: Provides a listener to exit the program when the window exits
• SimpleSwing: Creates a simple-to-use Swing component
• ImagePanel: Provides a canvas to display and repaint images

• ImageViewer: Renders and displays images
In the next chapter, we’ll use the classes created here, as well as the Java Media Frame-
work, to display images and video from a webcam.

6.1 Image Capture

Once you install the Java Media Framework, test the installation by running JMStudio. JMStudio
detects your capture devices (both audio and video). Go to File ➤ Preferences (see Figure 6-4).
This brings up the JMF Registry Editor (see Figure 6-5). Select the Capture Devices tab and then
click Detect Capture Devices. After a moment, the right pane will display the capture devices
details.

■Note The Locator identifier is on the second line of text. This locator will be what we use in the rest of the
chapter to identify your webcam.