COPYING DETERRENTS AND CONTENT PROTECTION
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
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
DVD-Video Region Codes
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.
CONTINUE TO DUPLICATION,
REPLICATION AND PUBLISHING