The answers to everything duplication blog

Many now consider DVD video copy protection a crucial part of the project. It is equally important to understand how it works and the different options for the money to be well spent. So what is copy protection? How does it avoid piracy?

Content Scrambling System (CSS)

In this copy protection method, audio and video data on the DVD discs are encrypted with a specific key that can only be decrypted by DVD players authorized by the DVD CCA (DVD Copy Control Association http://www.dvdcca.org). Each title will have its unique encryption key. Most DVD players sold in the US are equipped with the ability to decrypt scrambled data.

CSS is carried out in the glass mastering stage of replication. During authoring, the CSS flag needs to be checked. For this reason, a DLT master should be submitted.

Macrovision Analog Copy Protection (ACP)

Perhaps the most effective means of copy protection, patented and developed by Macrovision, it boosts the ability to protect DVDs against being copied to VCR and DVD recorder. It causes recorders to make distorted copies, with no entertainment value. DVD CCA requires that all DVD playback and recorder devices sold in the US recognize ACP technology.

Clients needing Macrovision’s ACP technology need to request it at the time of authoring. The ACP flag will then be added to the DLT master. The copy protected master will be replicated at the manufacturing facility. The clients will also be charged at a per disc basis, reportable to Macrovision.

The latest copy protection technology from Macrovision is RipGuard. According to Macrovision, it plugs the digital hole, which reduces ripping of DVD. This technology is fairly new, and right now it is unclear how many DVDs released have employed it.

CGMS

CGMS is another copy control system. There are 3 copy states in this system: copy enable, copy once only and copy never. The states can be added during authoring. Currently this technology is not commercially patented and not enforced by DVD CCA. Few DVD players in the market have the technology to read these flags. It is somewhat ineffective because many playback and recorder device is not equipped to decode. Even if the DVD is flagged with ‘Never Copy’, it can still be copied.

Region Coding

DVDs can be region coded so that a US made DVD cannot be played in Asia, Europe etc. There are currently 6 regions, such codes are established to allow titles to be distributed in different parts of the world at different times.

The region codes are:
1: U.S., Canada, U.S. Territories
2: Japan, Europe, South Africa, and Middle East (including Egypt)
3: Southeast Asia and East Asia (including Hong Kong)
4: Australia, New Zealand, Pacific Islands, Central America, Mexico, South America, and the Caribbean
5: Eastern Europe (Former Soviet Union), Indian subcontinent, Africa, North Korea, and Mongolia
6: China

Each DVD player is given a region code and will only play discs that are coded with the same region. Discs can also be all-region; which means they will play in any DVD players around the world. Region coding does not apply to recordable DVDs. Therefore, DVD burned on a PC will be region-free.

Region code is not an encryption system, however it still needs to be set during authoring.

Conclusion

When deciding which copy protection to employ, consider the following:

- the DVD player standards where the DVDs will be distributed
- budget for copy protection; applying copy protection often times require paying an additional fee for replication, authoring and licensing.