Dune: Special Edition

A Conversation with Michael Costa, Director of Stream AV, who authored this DVD

Dune was released in Region 4 about 2 years ago. The transfer was infamously bad. Force Video and Infogrames have taken the bull by the horns and gone back to the drawing board with this title, remastering it from scratch. In addition, they have added a unique bonus - a dts audio track, created from the original uncompressed 6 channel audio master tracks.

When I heard that this title was to be given the treatment that it deserves, I was keen to speak to the people involved about the technical aspects of creating this remaster, and I was grateful to be able to speak with Michael Costa from Stream AV.

The initial release of Dune was authored from very ordinary source materials. What audio and visual source materials were made available for this remaster of Dune?

We were delivered a Digital Betacam tape which is the usual delivery medium for DVD production. Audio-wise, the surround mix was delivered on a set of 2 DTRS formatted digital audio tapes (aka DA-88 format). These unfortunately had timecode on them that bore no relation to the video timecode, so the entire soundtrack had to be re-conformed and re-synced.

Is the video source material an NTSC to PAL conversion?

Yes it is, though we were assured that this was done using Alchemist - the most high-end standards converter available.

Are these source materials the best that are available?

At this point in time, absolutely.

I am lead to believe that this remaster is not 16x9 enhanced - any reason why not (eg lack of source materials)?

These were the highest quality source materials that could be obtained - and believe us, there was an extensive search spanning the last six months or so.

Why was the decision made to add a dts audio track to the Dune DVD?

As an authoring facility, we only recently got hold of a DTS solution. We happened to mention to Infogrames that we were just beginning to tinker with it, and they were immediately very excited at the prospect of having a DTS track for Dune, so we went for it.

What was the source material for the DTS track - an uncompressed PCM master? or something else?

It was an uncompressed PCM master from the DTRS tapes mentioned above. They were 16 bit, 48K masters, though this format does allow for 24 bit resolution as well.

What is the bitrate of the DTS track going to be? 754kbps or 1509kbps?

It's the full 1509kbps - we knew it was just going to fit, so we thought that we'd throw the lot at it!

What other audio tracks are on the DVD, and what are their bitrates?

There's a Dolby Digital 5.1 at 448kbps as well as a Dolby Digital 2.0 at 192kbps.

What additional steps are involved in authoring a DVD with a DTS track over and above one with only Dolby Digital tracks?

Assuming you've done all your editing and/or sweetening [if necessary] of the uncompressed audio tracks, the reality is that you just need to create a DTS compliant stream. This might be a real-time process or an off-line process. It's pretty much the same methodology as creating an AC-3 compliant stream, though they both have their own specific parameters that need to be set.

What influence does adding a DTS track have in general to a DVD's space requirements? What about specifically for Dune?

The biggest drawback of all these wonderful audio formats concurrently, is that they steal valuable bit-space away from the pictures. It can become a bit of a juggling act. We were seriously contemplating doing the DTS track at 754kbps, but we knew that if we'd done that, people would have reviewed the disk and complained that we didn't use the upper rate even though it would have fit on the disk. The balancing act is not always about whether the disk will fit the data, but rather whether the cost to the picture is too much.

What is your opinion of Dolby Digital at 384 and 448 kbps versus DTS at 754 or 1509 kbps? Is there a significant difference?

Our only serious testing to date is with a 448 Dolby Digital stream comparing directly with the PCM masters we used to create the stream. There's certainly some degradation there, but when you consider the incredible amount of data that's being discarded, it's pretty darn impressive! The bottom end loses some of its tightness and authority, but the real damage is done in the higher frequencies. Without getting too bogged down in subjective "hi-fi language," much of the air is lost and the mid-highs that were previously distinct tend to sound clumped together. This is more problematic with music titles than movies, and this might explain why many music titles are being released with DTS these days.

We have yet to do our own conclusive tests with the two DTS rates, but have done significant "armchair" research which has shown the jury to still be well and truly out. Some claim that 754 DTS is actually outperformed by Dolby 448. Others say that 754 DTS is virtually as perfect as 1509 DTS, losing out only during extremely harmonically rich passages. One thing that everyone seems to agree on is that 1509 DTS is as good as it gets without using uncompressed data.

How do you think the final DVD is going to look and sound?

On the whole, pretty good. We're hoping that this region 4 version gets the nod as the one to buy against all the other regions, but let's not forget that this is a 17 year old product - and to be honest, the film hasn't held up as well as some other masters from this era. The video we were given was slightly soft, almost to the point of being blurry at times.

Using our Snell & Wilcox MPEG pre-processor, we made the decision to actually enhance many scenes as well as simply reducing noise. While this had the very positive effect of sharpening the picture and extracting significantly more detail, it also had the negative effect of bringing up the aliasing and edge enhancement type artifacts. We were watching it happen between gritted teeth but again had to make a creative decision based on what we thought was best overall. The source was really quite
erratic too. One scene might be beautifully crisp and another particularly bad, so this enhancement was an attempt to create some uniformity.

Thank you for your time.

No problem at all.