Patent ID: 7268834

Claim:
An apparatus for combining a first video signal with a second video signal, wherein said video signals represent video images and wherein at least the first video signal represents a sequence of video images, said apparatus comprising: i) a first input for input of the first video signal, ii) a second input for input of the second video signal, iii) an output for output of a third video signal, iv) a keying-pattern detector connected to said second input for detecting a predefined repetitive pattern, wherein said keying-pattern detector comprises: a means for receiving and/or storing a representation of the predefined repetitive pattern, and an output that is arranged to provide a signal indicating whether said predefined repetitive pattern is detected or not, and v) a video switch connected to said first input, said second input, said output and said output of the keying-pattern detector for continuously selecting a video signal from one of the first and second input to be represented in a third video signal, said selection being controlled by a signal from the output of the keying-pattern detector; and wherein said predefined repetitive pattern includes consecutively arranged sub-patterns.