EP0171829A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Improvements relating to video editing systems
Assignee: Quantel Ltd
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Filing: 1985-07-02
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Granted: —
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Expires: 2005-07-02
Abstract
Abstract A system for combining two or more video signal inputs using a chroma key like system. The keying is not done to one colours, like saturated blue, but to any colour within a range. One of the video signal inputs 1 is frozen and appears as a still picture on a display 6. Graphic means (16) are used to define an area of the picture and the maximum and minimum values of the colour components of the signals in that area are detected. Whenever a signal with components falling within the detected range is present in a switch (14) it operates to select a channel for output, this works to build up a composite picture.
Inventors
- 👤 Robin Alexander Cawley
- 👤 Roderick Jermyn Pratt
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 18:52
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/64; H04N9/74; H04N9/75
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
127 words
A video signal editing system comprising at least two input channels (1), (2), for video signals representing different pictures, an output channel (15), switch means (14) for selectively outputting the video signal from one or another of said input channels to said output channel (15) in dependence on the presence or absence of signals in one of said channels denoting a predetermined characteristic, characterised by means (16) for defining an area of the picture represented by the signals in said one channel, means (13) for detecting the range of signals in said area, denoting said characteristic, said switch means (14) being arranged to perform the relative switching in dependence on the presence or absence of signals in said range of values or in a range related thereto.
Claim 2
Dependent Claim
127 words
A video signal editing system comprising at least two input channels (1), (2), for video signals representing different pictures, an output channel (15), switch means (14) for selectively outputting the video signal from one or another of said input channels to said output channel (15) in dependence on the presence or absence of signals in one of said channels denoting a predetermined characteristic, characterised by means (16) for defining an area of the picture represented by the signals in said one channel, means (13) for detecting the range of signals in said area, denoting said characteristic, said switch means (14) being arranged to perform the relative switching in dependence on the presence or absence of signals in said range of values or in a range related thereto.
Claim 3
Dependent Claim
69 words
A system as in Claim 1, characterised in that said area defining means includes freeze frame means (17) for displaying a still picture of a frame of video signals in one channel, video graphic means (16) for designating on said still picture the boundary of said area and means (8) for generating address signals for applying video signals representing the picture points in said area to said detecting means.
Claim 4
Dependent Claim
22 words
A system as claimed in Claim 2, characterised in that said video graphic means (16) includes touch tablet and stylus means (7).
Claim 5
Dependent Claim
19 words
A system as in Claim 1, characterised in that said predetermined characteristic is the colour of said video signals.
Claim 6
Dependent Claim
36 words
A system as in Claim 4, characterised in that said switch means (14) further includes means operative in response to the presence of signals within the range of colour detected to selectively switch the input channels.
Claim 7
Dependent Claim
34 words
A system as in Claim 5, characterised in that said switch means (14) operates when signals representing three colour components are within the range detected for each component to selectively switch the input channels.
References Cited (Backward Citations)
No citation records indexed.
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