Digital on-screen graphic

A digital on-screen graphic (originally known as digitally originated graphic, and known in the UK and New Zealand by the acronym DOG; in the US, Canada, Ireland and Australia as a bug) is a watermark-like station logo that most television broadcasters overlay over a portion of the screen area of their programs to identify the channel. They are thus a form of permanent visual station identification, increasing brand recognition and asserting ownership of the video signal. In some cases, the graphic also shows the name of the current program. Some television networks use an on-screen graphic to advertise upcoming programs (usually programs scheduled later the same day, but also for "significant" upcoming programs as much as a week in advance).

The graphic identifies the source of programming, even if it has been time-shifted—that is, recorded to videotape, DVD, or a digital personal video recorder such as TiVo. Many of these technologies allow viewers to skip or omit traditional between-programming station identification; thus the use of a DOG enables the station or network to enforce brand identification even when standard commercials are skipped.

DOG watermarking also helps minimize off-the-air copyright infringement (for example, the distribution of a current series' episodes on DVD): the watermarked content is easily differentiated from "official" DVD releases, and can help law-enforcement efforts by identifying not only the station an illegally copied broadcast was captured from, but usually the actual date of the broadcast as well.

Graphics may be used to identify if the correct subscription is being used for a type of venue. For example, showing Sky Sports within a pub requires a more expensive subscription; a channel authorized under this subscription adds a pint glass graphic to the bottom of the screen for inspectors to see. The graphic changes at certain times, making it harder to counterfeit.

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