Abstract: A television receiver for extended definition television carries out scanning line interpolation in a way that eliminates picture shift on the screen and ensures normal display when supplied with a non-standard video signal having a scanning line count of other than 262.5 lines per field. The television receiver includes a scanning line interpolation circuit, a normal video signal detection circuit and a interpolation controller. The scanning line interpolation circuit effects scanning line interpolation using either data in the current field or out-of-field data as per the result of motion detection in the picture. The normal video signal detection circuit distinguishes the normal video signal from other signals by detecting the number of scanning lines involved. The interpolation controller causes the scanning line interpolation circuit to effect scanning line interpolation using only the inside-field data if the supplied signal is a non-standard signal.

Abstract: Intermediate vertical synchronizing signals are generated to occur between the vertical synchronizing signals normally included in a conventional video signal. A first counter counts clock signals which are synchronized with the horizontal synchronizing signals normally included in the conventional video signal to provide a count representing the number of clock signals which are present in one-half of a field interval of that conventional video signal. The count provided by the first counter during the second preceding field interval is temporarily stored and compared to a count produced by a second counter which counts the clock signals from the beginning of the field interval. An intermediate vertical synchronizing signal is generated when the count of the second counter is equal to the stored count.

Abstract: In a picture-in-picture television receiver, the subpicture signal is A-D converted; the converted digital subpicture signal is latched in response a subpicture clock in synchronism with a subpicture synchronizing signal; the latched signal is latched again and stored in an image memory in response to a main picture synchronizing signal; and the latched signal is read from the image memory in synchronism with the main picture synchronizing signal, in order that the subpicture can stably be inserted in a predetermined area of the main picture by eliminating the unstable data duration during which variation in the subpicture signal is different for each bit signal thereof.