Abstract: There is disclosed a multi-screen generating circuit capable of freely displaying on a main screen a plurality of multi-screens corresponding to 4 sub-screens, 9 sub-screens, 13 sub-screens and 16 sub-screens according to size of the main screen, the circuit also being capable of giving free choices in selecting any type of multi-screens regardless of the number of broadcasting channels which may differ from one region to another. The inventive subject to carry out the object of the invention includes: a command decoder 10, an address signal generator 20, a writing reference signal generation circuti(WRS) 30, a writing display controller 140, an analog-to-digital clock generator 188, a first multiplexer 60, a serial-parallel converter 50(SPC) 50, a write timing generator 70, a read timing generation circuit 80, a latch section 90, and a data multiplexer 100.

Abstract: Disclosed is an address producing circuit for zoom function in which horizontal and vertical addresses are to make more free selection of a partial picture around a plurality of locations disposed on a screen of a monitor device, and image data stored in a predetermined address region according to the selection is read out to display on the screen, so that the picture of the selected partial region can be magnified to a whole screen picture.

Abstract: There is disclosed an image processing circuit for displaying a plurality of sub-pictures which have different image signal sources on a common screen. The inventive subject digitalizes an original image analog signal by use of a corresponding sampled signal upon a multiple picture processing, saves the digitalized data almost simultaneously, and uses a dual-port memory for reading the data, whereby the circuit simplifies the generating process of a control timing signal and renders the PIP process easy to carry out, when controlling the dual-port memory by read-write operation. The apparatus for carrying out the invention includes a keyboard or remocon for data input/output, a microcomputer for controlling the entire process, a controller for controlling display processes, an analog switching device, an A/D converter for converting the analog signal to a digital signal, a dual-port memory for dealing with various image signals, and three D/A converters for converting digital data to analog data.