A television receiver is disclosed, which receives two television signals and compresses a time axis of one of the television signals and inserts the compressed signal to a portion of the other television signal to display both signals on the same screen. A signal indicating a boundary of the two images is produced from a synchronizing signal derived from one of the two received television signals and the boundary indicating signal is superimposed on one or both of a brightness signal and a chrominance signal to display the boundary.
The write clock controlling operation of the PIP circuitry (e.g. the analog digital converter in the PIP channel) utilizes a clock signal source having a substantially higher frequency (preferably six times) the desired write clock frequency. This clock signal is applied to a divide by six circuit which has a cycle reset controlled by the horizontal synchronization signal of the incoming PIP signal. The write clock signal furnished by this arrangement has the correct rate for sampling the incoming PIP video information and is pseudo line locked to the PIP horizontal synchronization signal.
A method for producing a frame around a video image includes the step of placing subframes around a base frame. The subframes have an offset with respect to the base frame, in order to generate a plastic impression of the frame. The base frame and the subframes are produced from the same frame signal. A device for producing such a frame is also provided. The method and the device are in particular used in picture-in-picture systems.
An image processing system, which receives asynchronous analog video output signals from a plurality of independently operating video cameras (preferably four) and simultaneously displays the image obtained from each camera, dimensionally reduced by a factor of two, on a non-overlapping basis on one video monitor, is described.
A television receiver having first and second tuners which can receive the same frequency band and display multiple-surfaces includes key inputting means for indicating that the display of a second tuner picture in a plurality of tuners is on or off and channel selection controlling means for making the second tuner an ordinary selected condition when the key inputting means indicates that the display of the second tuner picture is on and fixing the second tuner's local oscillation frequency so as to set a frequency received by the second tuner outside a receivable frequency band when the key inputting means indicates that the display of the second tuner picture is off. Thereby, mutual beat interference between the plurality of tuners is eliminated.
In order to selectively reduce the size of an auxiliary image, such as may be displayed within main image during a so called "picture-in-picture" or "PIP" mode of operation of a television system, a fixed amount of the auxiliary image is caused to be cropped from the auxiliary image without changing the compression ratio of the compressed auxiliary video signal from which the auxiliary image is derived.
