By Chris Lamb

I want to prevent my DVDs from being copied illegally. How well do the currently available copy protection methods work?

I’m going to assume you are referring to a DVD video title, and that is how I will base my answer. (If I have missed the mark and you are more interested in DVD-ROM copy protection, drop me a quick note).

There are two primary components to DVD-Video copy protection: analog and digital. Macrovision is the cornerstone of the analog copy protection with their ACP-DVD product. It prevents individuals from making a copy of the DVD through the analog outputs on their DVD player. It utilizes an embedded "stripping" in the video signal that significantly degrades the recorded output, rendering it unusable.

The digital aspect of copy protection is covered by CSS, Copy Scramble System. CSS prevents the copy of a DVD to a hard drive or to a P2P (Pier 2 Pier network) for sharing. Unfortunately, CSS was cracked almost immediately after its release, leaving a big hole in digital copy protection. In a response to DeCSS, Macrovision has recently released a new digital copy protection tool called RipGuard to close the hole.

There are excellent tools available to make it nearly impossible for an average user to make an illegal copy of a DVD-Video. However, like the people who create computer viruses, there are individuals that lay siege to the available anti-piracy technologies in the hope of cracking them. In some cases they are successful.

DVDs played on a computer don’t seem to have the same level of quality as DVDs played on a television. Why?

There are literally thousands of answers to this question. We could dedicate a book to this topic (not that anyone would want to read it). Here are the basics. Most computers rely on software DVD decoders to process and emulate DVD playback. DVD set-top boxes use hardware decoders to achieve a more reliable playback. The processing quality of your computer and amount of compression can have a negative impact on the quality of playback on your computer. If you are experiencing a quality issue, first make sure there are no other applications running in the background that could be hogging processor time. Next, get updated software. Software bugs and incompatibility are large contributing factors to poor quality playback.

The issues are numerous and variable. Keep in mind that DVD playback on a computer is "emulated" by the software decoders and is never going to be perfect.

There are tools out there that would enable to you achieve a very high quality playback on a computer, some say even better than you can achieve with a set-top box. Drop me a note if you are interested and I will send you more information.

Chris Lamb is a partner and chief technical officer for Paragon Media. He has over 12 years experience in the optical and print media industries.

Send your media related questions to Chris at chris@ParagonGroup.com. Answers will be printed in Media Inc. or available online at www.media-inc.com.