Text radio and device for teletext decoding

摘要

A full-screen still-image of text-broadcast information is converted into a scrollable page that is then superimposed and scrolled on the current TV picture on the display screen, thereby enabling a user to view a correct and complete information while enjoying the TV program. An input control portion 1 extracts text-broadcast information superimposed upon unused lines in an ordinary TV video signal transmitted during a vertical blanking period and generates an interrupt to a CPU processing unit 2 which in turn converts coordinates of the received character data into addresses in a presentable image conversion table 7b. CPU2 selects a suitable display area through a display control portion 6 and scrollably displays the image thereon through a scroll display control portion 2a according to the prepared conversion table. This method can prevent the scrolling image from overlapping another subtitle on the TV picture and improve the visibility of the information. MATH