The user operation prohibition (abbreviated UOP) is a form of
use restriction used on video
DVD discs and
Blu-ray
Blu-ray (Blu-ray Disc or BD) is a digital optical disc data storage format designed to supersede the DVD format. It was invented and developed in 2005 and released worldwide on June 20, 2006, capable of storing several hours of high-defin ...
discs. Most
DVD players and Blu-ray players prohibit the viewer from performing a large majority of actions during sections of a DVD that are protected or restricted by this feature, and will display the
''no'' symbol or a message to that effect if any of these actions are attempted. It is used mainly for
copyright notices or warnings, such as an
FBI
The Federal Bureau of Investigation (FBI) is the domestic Intelligence agency, intelligence and Security agency, security service of the United States and Federal law enforcement in the United States, its principal federal law enforcement ag ...
warning in the United States, and "protected" (i.e., unskippable)
commercials
A television advertisement (also called a commercial, spot, break, advert, or ad) is a span of television programming produced and paid for by an organization. It conveys a message promoting, and aiming to market, a product, service or idea. ...
.
In 2003, most, if not all,
DVD Copy Control Association licensed DVD players implemented UOP. Player manufacturers were required to detect and respond to UOP commands as a condition of obtaining a license from the DVD Format/Logo Licensing Corporation.
Countermeasures
Some DVD players ignore the UOP flag, allowing the user full control over DVD playback. Virtually all players that are not purpose-built DVD player hardware (for example, a player program running on a general purpose computer) ignore the flag. There are also
modchips available for some standard DVD players for the same purpose. The UOP flag can be removed in
DVD ripper software such as:
DVD Decrypter,
DVD Shrink
DVD Shrink is a freeware DVD transcoder program for Microsoft Windows that uses a DVD ripper to back up DVD video. It can also be run under Linux using Wine. The final versions are 3.2.0.15 (English) and 3.2.0.16 (German); all other versio ...
,
AnyDVD,
AVS Video Converter,
Digiarty WinX DVD Ripper Platinum,
MacTheRipper,
HandBrake and
K9Copy. On many DVD players, pressing stop-stop-play will cause the DVD player to play the movie immediately, ignoring any UOP flags that would otherwise make advertisements, piracy warnings or trailers unskippable.
Hit Stop -> Stop -> Play and Other Tricks to Skip DVD Trailers and Warnings
Lifehacker, 2010
Nevertheless, removing UOP does not always provide navigation function in the restricted parts of the DVD. This is because those parts are sometimes lacking the navigation commands which allow skipping to the menu or other parts of the DVD. This has become more common in recent titles, in order to circumvent the UOP disabling that many applications or DVD players offer.
Newer DVD players (i.e. post-c. late 2010) have, however, been designed to override the aforementioned counter-countermeasures. The DVD reader software inside the DVD player automatically generates chapters for parts of the DVD lacking navigation commands, allowing them to be fast-forwarded or skipped; pressing the menu button, even in these previously restricted sections, will cause a jump to the main menu.
See also
* Comparison of DVD ripper software
* DVD Copy Control Association
*Hacking of consumer electronics
The hacking of consumer electronics is a common practice that users perform to customize and modify their devices beyond what is typically possible. This activity has a long history, dating from the days of early computer, programming, and elect ...
References
External links
User Prohibited Operations flag documentation
Unofficial DVD Specifications (archived)
* {{US patent, 6553180
Microsoft Windows DVD Info, Get Current UOPS
List of User Operations that can be controlled by this flag.
Digital rights management
DVD
Hardware restrictions