Copyright OSTA 2004
All rights reserved.


Understanding DVD

Author's Notes
Physical Logical and

Recording Hardware
Recording Speed
Physical Compatibility
Disc Size Configuration and Capacity
>Copying Deterrents and Content Protection
Duplication, Replication and Publishing
Disc Labeling
Disc Handling, Storage
and Disposal

Disc Longevity
Disc Testing and

Disc Construction and

Appendix A - Further
Reading and Resources

Appendix B - Industry
and Product Contacts
About OSTA
About the Author







Can commercial DVD-Video and DVD-Audio discs be copied onto writable DVDs?
To deter users from making disc-to-disc and other direct digital copies of commercial movies and audio albums, most prerecorded DVD-Video and DVD-Audio format discs are protected at the factory using (respectively) the Content Scrambling System (CSS) and Content Protection for Prerecorded Media (CPPM).

CSS and CPPM selectively encrypt disc sectors that can only be decrypted during playback by licensed products (DVD players, computer DVD playback software and others). Critical information (decryption keys, album identifiers) required to unlock content is located in protected regions of these discs (Control Data Zone of Lead-in Area and sector headers) accessible to the player or drive and under only carefully regulated circumstances. Without these keys the encrypted video or audio is unusable. Performing bit-for-bit duplication or simply copying files from the disc to a writable DVD, hard drive or other storage medium will not yield a useful reproduction.

As a further defense, writable DVD products employ several safeguards to prevent valid CSS decryption keys and CPPM album identifiers from ever being written to these discs. For example, blank writable DVD discs come from the factory with the Control Data Zone of their Lead-in Areas already “prewritten” (DVD-R General) or embossed (DVD-RW, DVD-RAM) with dummy information. And, in the case of DVD-R (version 1.0), DVD-R (Authoring), DVD+R and DVD+RW, recorders are designed to write only dummy information in the same disc area (and sector headers). This also inhibits CSS or CPPM protection being conferred on content recorded on writable DVD discs for professional or other applications.

Nevertheless, over the years various computer software tools have emerged to allow the making of copies of CSS protected DVD-Video discs.

COPYRIGHT LAW must always be respected whenever dealing with content of any type. Products that bypass protection systems are not permitted in most jurisdictions. And even if a disc lacks content protection it does not mean that copying is permitted. OSTA does not support the use of writable DVD products for any unlawful purpose.

What is region management?
In addition to employing technology to discourage copying, CSS-encrypted DVD-Video discs may optionally contain region management information to allow commercial movie publishers to control the distribution of their products throughout the world. Discs (so enabled) and players contain information that specifies the geographic areas where they are to be marketed. To prevent discs intended for sale in one part of the world being distributed and used elsewhere all devices automatically check discs for region codes and only play titles for which they are authorized.

For computer DVD-ROM drives and recorders this task is accomplished through Regional Playback Control (RPC) of which there have been two phases. Phase I implementations were used prior to the end of 1999 and function through the computer’s video playing software, decoding system or operating system to manage region control. In this case, the region code could be set only once and, for some decoders, the region was sometimes even preset at the factory. Phase II implementations have been in use since 2000 and hand-off responsibility for region management exclusively to the drives and recorders implementing the necessary functions in their firmware. Generally speaking, the user can change the region code up to five times with the manufacturer having the additional ability to then service the unit and reset this counter (up to four times).

Assorted workarounds to region management exist in the marketplace (typically outside North America) including “multi-region” DVD players that read discs regardless of region codes. As well, altered computer DVD-ROM drive and DVD recorder firmware is sometimes circulated to achieve the same effect. Be aware, however, that such modifications can invalidate product warranties.

DVD-Video Region Codes

Region Code
Geographic Region
United States, Canada
Japan, Europe, Middle East, South Africa
South East Asia (including Hong Kong)
Australia, New Zealand, Mexico, Central and South America
Northwest Asia, North Africa
Special purpose (aircraft, cruise ships, hotels)

What is Content Protection for Recordable Media?
Sometimes analog or digital broadcasts (typically in Japan) are identified to allow only one copy to be made by a viewer and by using the Content Protection for Recordable Media (CPRM) system, such material can be encrypted and recorded once to a writable DVD disc. As it is currently marketed, CPRM is an option found only in some consumer electronics (CE) DVD recorders that write DVD-RW and DVD-RAM discs using the DVD Video Recording format (DVD-VR). This allows material specifically flagged “copy once” to be written to a single disc but prevents that disc from then being further duplicated. This is accomplished by binding the content to the particular disc through encryption employing, among other things, a code (media identifier) unique to each writable disc compliant with the CPRM system. This one-off code is inserted at the factory into the special Narrow Burst Cutting Area (NBCA) of a DVD-RW or Burst Cutting Area (BCA) of a DVD-RAM disc and, as such, cannot be duplicated by a DVD recorder.

Be aware that not all DVD players, drives and recorders that play or write DVD Video Recording formatted (DVD-VR) discs are compatible with CPRM and that not all blank DVD-RW and DVD-RAM discs are equipped with the NBCA or BCA necessary to handle CPRM content. If in doubt, consult with the hardware or disc manufacturer.