Page 202 - The Definitive Guide to Building Java Robots

Preston_5564C06.fm Page 183 Friday, September 23, 2005 5:13 AM

CHAPTER 6 ■ VISION 183

public void setImage(BufferedImage image) {
this.image = image;
}

public ArrayList getParameters() {
return parameters;
}

public void addParameters(Object parameter) {
parameters.add(parameter);
}

public String getName() {
return name;
}
}
Next, for basic image processing, I’ll perform the following operations:

• Change an image to greyscale (pixel)
• Threshold an image (pixel)

• Resize an image (area)
• Detect motion (pixel)
But to render these, I want to create a class that displays two images. The first is the original
image from the webcam, and the second is the image after it’s processed. While you need to do
this for your robot, it’s nice for debugging.

Code Objective
The code objective in this section is to create a class that can view the images before and after
they are processed.

Code Discussion
First, I’ll reuse the WebCamViewer created in the last section by extending it. The fields in this
class are two ImagePanels: one for the original image and one for the processed image. The
final field is an ArrayList that I’ll use to keep the list of FilterParameters.
The constructor calls super() for the camera and then calls init2(), which initializes the
current class to a later size and adds the two panels side by side.
The getPic() method from the parent class is overloaded so I can, one, set the current image
into the srcPanel, and two, call the doProcessing() method for the dstPanel. By overriding the
parent method, I can reuse the call to getPic() from the timer created in the parent class.
The doProcessing() method creates a class ImageProcessor, and then based on the number
of filters in the list, it iterates and processes all the filters before returning the image to the
getPic() method, where it can be set in the dstPanel or right pane.