* Collect image URLs and related information from Soundslides slideshow.
*/
private void parseSlideshow(String slideshowUrl)
throws IOException, ParserConfigurationException, SAXException, XPathExpressionException {
XPathParser parser = new XPathParser(slideshowUrl + "soundslide.xml");
NodeList slides = parser.find("/edit/slides/slide");
String imagesDirectory = "600_450/";
int imageCount = slides.getLength();