Rivergate Software Inc. - makers of DVDAfterEdit

by Ian Shepherd

• Probably the most extensive and demanding post-authoring project ever undertaken
• One of the most legendary, some would say infamous music titles ever produced on DVD
• Merge both sides of a DVD-10 disc - ie. two DVD-5s - into one new DVD9
• Entirely replace the original menus and navigation
• All without access to any of the original assets, producers or programming team

Originally released in 1998, "Deja Vrooom" is a live concert DVD like no other. It includes multi-angle sections allowing the user to watch any musician in the band and also listen to a dedicated mix highlighting their particular instrument. It contains several hours of footage including DTS 5.1 surround-sound, plus nearly a hundred pages of biographical information and images. It has multiple bonus features including rehearsal and studio out-take footage and even a mind-mangling "game" which allows the user to specify a unique audio mix for the song "In The Court Of The Crimson King". Choose a singer, soloist or rhythm section from different performances spanning twenty years and hear the result - one of 64 different possible versions of the same song, accompanied by 8 different slideshows all cut in time with the music... all this amounts to a brief which would challenge even the most accomplished of authoring teams !

The additional challenge facing SRT's post-authoring engineers for the new release of this disc in 2006, was to completely replace the menus and navigation of the original, while squeezing all the content of the original double-sided disc onto a single DVD-9, without access to any of the original assets - footage, stills, or even the original authoring team. Several months of ground-breaking work later, the end result is a stunning, seamless re-interpretation of a much-loved classic into a cleaner, leaner, "classic" DVD interface far better suited to our current high-speed "broadband" expectations.

Background

The original 1998 release of this title is widely acknowledged as a pioneering classic of the Music DVD medium. King Crimson as a band has existed in one form or another since 1968, always centering around the enigmatic figure of guitarist Robert Fripp, with other key figures over the years including Tony Levin on bass, a long-term member of Peter Gabriel's band; drummer Bill Bruford and guitarist/vocalist Adrian Belew, who has played with Talking Heads, amongst others. Their music is complex, often challenging and relies heavily on improvisation, and the intention was that the menu design of the original disc should seek to reflect that. They succeeded but perhaps went almost too far in pursuit of their goal, since many users actually felt the original interface was virtually unusable !

Imagine menus where the buttons are spread unevenly around the screen and only one at a time is visible. Not only that but the paths from one button to another aren't always intuitive or consistent... It's an intriguing concept, and in fact can actually work quite well on a computer player or simulation, but unfortunately the very noticeable delay or "lag" in moving from one button to the next on most players makes for a very frustrating "real-world" experience.

So for the 2006 re-release, it was decided that the old menu system should be completely replaced with a more straightforward version, with all-new artwork. And at the same time, both DVD-5 sides of the original DVD-10 should be combined into a single-sided DVD-9, allowing the complete concert to be viewed in it's entirety without flipping the disc.

"Post-Authoring"

Traditionally, a project like this would need "re-authoring from scratch" - where unfortunately it is necessary to completely disassemble the original disc; separating, identifying and labeling all it's constituent parts - audio, video, menus, button overlays, subtitles etc - and then rebuild the whole thing as if it were a brand new job, incorporating the necessary changes. In the case of a title as complex as "Deja Vroom" where the original authoring probably cost tens of thousands of dollars, this would be a truly herculean task, requiring a great deal of time and costing a huge amount of money - if it was even possible to keep track of all the "exploded" assets at all.

In contrast, SRT chose to use a cutting-edge piece of software called DVDAfterEdit, which offers a unique new facility - "Post-Authoring". This process is much quicker and more efficient than traditional "re-authoring", allowing us to make modifications directly to the original files themselves, without touching the existing structure at all to begin with. The process is more one of "merging" what already exists, rather than rebuilding from scratch - so, all the hard work and money that went into authoring the original discs is preserved, and time doesn't have to be spent unnecessarily re-doing it. For this reason the method is called "post" - authoring as opposed to traditional re-authoring.

DVDAfterEdit in action

The first part of the process was pure detective work. DVDAfterEdit can open any unencrypted VIDEO_TS folder from an existing DVD or DLT tape, and simulate it's playback in a DVD Player using it's integral debugging module - Tracer. Using the "Show" button to reveal where navigation "is" at any point in the simulation quickly allowed us to identify where all the major assets and menus were located in the disc's structure. Tracer additionally constantly displays all the player's SPRM and GPRM registers allowing us to see how the original authors controlled it's interactive features.

Next we took the first and most major step to combining the two sides of the disc into one. A huge limitation of the original double-sided DVD10 presentation was that the user had to turn the disc over to watch the second half of the concert. Having copied both sets of files to hard disk, we were able to use DVDAfterEdit's immensely powerful "Import VTS" feature to take the second half of the concert from "Side B" and add it to the end of the "Side A" disc - including all it's advanced multi-angle functionality, multiple audio mixes and all. We then simply modified the commands which determined what happened when "Side A" finished to re-direct navigation to this newly imported "Side B" section instead of back to the main menu. In less than ten minutes, the disc was modified so that the concert would now play from beginning to end !

Of course, it wasn't all that simple. For example, both discs used the same DVD "register" to keep track of which song was playing. The new version therefore needed to be re-programmed to avoid any confusion between "Track 1" from the original Side A and Side B of the disc. DVDAfterEdit's ability to save out the entire command structure of a disc into a text file allowed us to use simple search and replace techniques to overcome this challenge, along with many other similar issues.

Additionally, all the extra bonus features were imported into the new VIDEO_TS folder in exactly the same way as the second half of the concert, and all the new menu buttons had to be programmed to hook into the existing programming code to restore the original interactivity for these features. We also used the "Replace VTS" feature to substitute new, re-compressed versions of some of the bonus features to save space and allow everything to fit onto one disc. The disc has an advanced multi-angle feature which allows different camera angles and audio mixes to be viewed on certain songs - even a random feature. We made extensive use of DVDAfterEdit's Tracer to discover how these kinds of features were implemented originally, and modified the original code to fit the new disc structure.

Conclusion

Work on the entire project was carried out over a period of more than a year, although amazingly the final version was actually created from scratch in only a couple of weeks ! When we started work, we didn't even know if DVDAfterEdit was capable of the task we were setting it, but we're delighted to say that it passed the test with flying colours. Choosing the DVD-9 layer-break, writing and verifying the final DLTs were all straightforward with DVDAfterEdit, and it's DVD Forum license give firm assurance that everything remains spec-compliant, even when major "surgery" has taken place, as in this case.

The post-authoring process not only produced a finished DVD-9 crammed to the absolute limit with features, but along the way even revealed a couple of truly obscure "easter-eggs" from the original discs that no-one but the original authors knew were there - not even band-members themselves ! The further into the process we got, the more apparent it became exactly how much time was saved by post-authoring rather than re-authoring from scratch.

This is one case at least where DVDAfterEdit not only made things easier and more efficient - without it, the entire project would have been literally impossible !

"Deja Vrooom 2006" will be released this summer.