DivX: An Introduction


While searching for information on the best techniques and technologies for delivering high quality video over typical "dial-up" or broadband connection speeds, one name kept coming up: DivX. For those who have never used this new media format, here's an introduction…

The problem was simple: I wanted to build up a high-quality video library for my amateur pay site, and so I turned to Stephen for help. While he has a great deal of video experience, it is focused on "videotape" and not on digital compression and suitable mechanisms for optimized, low-bandwidth web delivery, so I ended up doing some more searching.

The Search
While there are "many" options available for delivering video across the web, we had some specific criteria in mind, based upon our real world needs. These considerations included the fact that since these videos would be available exclusively in my "member's area" and would not be used on TGPs or in other "free" environments, quality was very important. After all, a pay site's success is often dependent upon member retention, rather than initial sales, so having decent content is a must. This ruled out the use of grainy, 160x120 reduced frame rate video clips.

At the other end of the spectrum, "full screen" high-resolution videos, while fabulous looking, were simply a bandwidth-draining nightmare, and totally unsuitable for the reality of the current marketplace, where 28k-56k dial-up connections are still the norm. While an increasing number of users had been migrating to DSL and cable, where available, these technologies are still not as widespread as many would like to believe. In fact, I can't get broadband here on the beach where I live, and typically won't exceed 33.6k on my dial-up, but can hit 52k on a real good day. This connection speed keeps me "honest" when it comes to the end-user experience.

Because we wanted to deliver reasonably sized video clips of at least VHS quality, we eventually settled on 320x240 pixel MPEGs, encoded at a high bit rate and with decent audio. The results of our initial tests looked very promising, and "entertaining" video clips of 2-4MB (a reasonable file size for dial-up downloads) are easily possible. The largest clip that I've done so far was around 15MB, which is far too large for dial-up downloads. While we could have "sliced" the large clip up into 10, 1.5MB files and provided members with some type of MPEG "stitcher" software (such as Ordix Mpack) which would allow them to easily build up their downloads into the larger file, we decided to look around for an easy, user-friendly alternative to traditional MPEGs. One that provided more sophisticated compression algorithms to enable higher quality with reduced file sizes.

The Potential
This brings me back to DivX. An outgrowth of the open source "Project Mayo," DivX is based upon MPEG-4, which is capable of compressing MPEG-2 files to a tenth of their original size. Consequently, this interests me to no end, and so I am currently hot on the DivX trail. According to their Web site:

"DivX™ video compression is a patent-pending software technology that compresses digital video so it can be downloaded over DSL or cable modems in a relatively short time with no reduced visual quality.

What does this mean for you? It means that now, for the first time, you can download full-screen, full-motion videos from the Internet that actually look and sound like what you get from your television or DVD player, and are not the size of postage stamps. With DivX compression technology, you can download and watch high-quality video on your television set or other convergence devices."

If the process lives up to the promise, DivX could be a boon for "real" amateur site operators and other video content producers. While I am not interested in the target application of delivering feature length films across the 'Net, if I could use DivX to squeeze a 15MB MPEG video clip down to around 2-5MB, for example, then anyone who visited my exclusive "member's area" would definitely need a generous supply of "Handy Wipes."

Stephen made DivX the XBiz "Download of the Week" this week so that anyone who was interested could easily obtain a copy. I have just downloaded my own copy and over the next few days will put it through its paces, and see what sort of results I can obtain using raw DV source footage. ~ Ayrora