Rivergate Software Inc. - makers of DVDAfterEdit

Advanced Content HD DVD is conceptually quite different from both SD DVD and Standard Content HD DVD. This section gives an overview of how it works, and links to resources with further information. Advanced Content offers a wealth of functionality far beyond the DVDs we are used to - check out tiles like "The Fast and the Furious - Tokyo Drift", for example - or, for something you could add to a project of your own, something like this. All this is achieved using HDi - Peter Torr explains it well in his blog:

"In a nutshell, HDi ("High Definition interactivity") provides the user interface between you and the HD DVD content. It is used to show the menu system, implement special features, play games, download network content, and so on. This interface is shown on top of the video so that you can do things like have pop-up menus that appear while the movie is still running (the HD DVD display is broken up into several "layers", including two video layers and the HDi layer).

Unlike DVD, where you typically have two "modes" of operation -- navigating through static full-screen menus to select chapters, audio setup, special features, etc.; and watching the video -- in Advanced Content HD DVD you really only have one "mode" where full HD-quality video is playing in the background, whilst a rich, fluid UI is running in the foreground. Obviously the background video doesn't have to be the main movie -- it could be some generic animated background, or a movie trailer, or just a black screen -- and the UI doesn't have to be visible all the time; in fact you would typically hide it while watching the movie."