Television receiver with multipicture display

A television receiver in which a single video signal can be reproduced simultaneously in at least two subareas of a picture screen, or at least two different video signals can each be reproduced in different subareas, with each subarea displaying either a reduced size picture or part of the picture supplied by a video signal source, said receiver comprising:

• a digital signal processing circuit for receiving signals from a plurality of video signal sources and converting said signals to picture data comprising luminance and color data for each picture element;
• a random access memory for storing picture data for an entire screen;
• a control unit for controlling the writing of picture data into an area of said random access memory, the area being selected depending on how many of said different video signals are to be reproduced on said picture screen and also depending upon an order by which lines of picture data are read from said random access memory, only selected lines being transferred from said video signal sources into associated areas of said random access memory;
• a digital to analog converter which receives picture data read from said random access memory and which generates therefrom analog red, green and blue signals;
• line counters, each having its respective count outputs coupled to said control unit, said line counters each being associated with one of said video signal sources and each being advanced between received periods such that at the beginning of a receive period it has a count corresponding to the line being received from the respective video signal source;
• a sensing circuit for sensing horizontal and vertical synchronizing pulses received in receive periods of said video signal sources to synchronize said line counters;
• and
• a signal source counter connected to said control unit that causes said control unit to periodically switch between selected ones of said video signal sources.