The Gad Berger interview

October 28, 1999

Gad Berger ( is the leader of the LSDVD [ ] project, whose goal is to bring a fully functional DVD player/decoder to the Linux operating system. Dave Klint and Paul Volcko are developers for the project.

Question and Answer Session

How would you define the state of DVD support for Linux at the moment?

Gad Berger: As of last night, there has been quite a turn of events. Currently, there is an open source AC-3 decoder, written by Aaron Holtzman, and for MPEG-2 decoding, you can use mpeg2player. What's kept the Linux community in the dark has been the Trade Secret encryption scheme CSS (Content Scrambling System).

I'm not sure where this will lead DVD development in Linux, or for that matter in industry, but now it's more of a "let's wait and see what happens."

LSDVD is currently developing a player that will interact with the upcoming hardware decoders that should show up on stores around Christmas, with Linux drivers. After creating a hardware-based decoder, we plan to make a solid software decoder available to the Linux community. We hope to open source as much of it as we can.

What was this turn of events? Has the secret of CSS been revealed?

Gad Berger: Yes they have. I don't know too much about the current standings of the decryptor, but I can tell you that last night I was in a friend's room watching both the video and audio streaming from a disc that was both unlocked, and the vob (video object file) was being piped through a css decryption program.

Right now, I have no idea what this means to industry, and all the keys that are given to companies ... but one can only speculate what may happen from here.

Paul Volcko: There is still an outstanding issue of IFO data format that the general Linux development community needs to solve before it can produce a full DVD player application.

On the LSDVD site, you say that the player will not be open source due to the licensing fees that you'd need to pay. What is the nature of these licenses?

Gad Berger: The licensing involved with producing a DVD Forum-compliant DVD player consists of licensing directly from the Forum (for recognition) and licensing from Dolby (for AC-3) and MPEGLA (for the MPEG decoding).

I am not very certain on how licensing works for CSS, but from what I understand, the licensing is free (as long as you are licensed with the DVD Forum), but it takes a while to attain.

Aside from that, there are a few expensive testing phases that the player has to go through before it can be placed on the shelves.

How do you intend to fund the initial licensing fees and testing phases? I would believe that they are non-trivial expenses.

Gad Berger: The LSDVD group as a whole is looking for funding to either create a company or work under a company so that we may distribute the product. The DVD Forum requires that licensing only go to a financially stable company. As does Dolby.

What is happening right now with the open-source community, in Linux DVD development, differs from us in that we are trying to produce a DVD player with all licensing. This gives us the advantage that the industry will work with us, and not against us. This means that we can talk to vendors like Creative Labs who don't regularly hand out specs, and help the community by offering drivers to hardware that is hard to develop for because of the lack of open specs.

So will LSDVD be a for-profit or non-profit project?

Gad Berger: Because of licensing and paying for royalties, LSDVD cannot be a fully free software package. We're thinking about selling it at a price that covers the royalties we incur for every unit sold.

Like I mentioned before, we will try to open source as much as possible, but we have to cover our costs as well.

But will you simply cover your costs or are your planning to make a profit as a corporation?

Gad Berger: The costs may be increased a little to pay for development. I'd love to give this out free and fully open sourced, but we need to eat as well :). We're not planning on charging an excessive amount though.

Paul Volcko: A lot will depend on if we start a company and try to sell this ourselves, directly, or if we make some kind of agreement with another company to produce this for them. The first option will likely involve a higher selling cost, whereas the later might be less, especially if the company gets peripheral benefits to selling it (besides direct profits).

Dave Klint: One of our goals is the advancement of the Linux and Open Source communities. Therefore, the best situation would be to produce this program, open sourced, free of charge. But because we have to pay royalties, it is unlikely that the program will be completely free. Whether or not we will start a company based on this is unclear at this time.

How much of your development do you think would be portable to, say, LinuxPPC on a Mac with DVD hardware?

Gad Berger: For the player itself, it won't take more than a day or so to port over. We're not doing anything at an extremely low level yet. When it comes to a software decoder, a lot of the assembly tweaking will be architecture specific. The reason we're able to do it this way, is because standalone DVDs have no idea of what an operating system is. Therefore we can implement our player as if it were a standalone.

When will I be able to buy DVD hardware from a computer store, install it on my Linux system, plunk in the Matrix DVD, and enjoy the show?

Gad Berger: As far as LSDVD is concerned, the team will be localized back at RIT (Rochester Institute of Technology) starting by mid-November. From there we will all continue work on the player that we started during the summer.

Since the hardware decoders (Sigma Designs EM8400 chipset and Convergence's card) will be out by Christmas, we will model our player to use their API. After that, we will work on software decoding, so you can watch your DVDs without a decoder, or with :). This goal may cost about 3 months total in design and implementation.

Paul Volcko: Realistically, 1 or 2 months before a card is out on the market probably and another week before a GUI is released to support either.

Dave Klint: Next week. :)

Our closing thoughts...

Thanks for your time, and I bid you good luck on the LSDVD project. I hope to be sitting at my desk watching DVD's instead of working sometime soon!

Copyright 1999