Decoding information pages having header information and page data

In a technique for decoding pages of subtitle data supplied as information pages which include respective headers and page data (i.e. subtitle character data) which are superimposed on a video signal, each received information page is stored in a ring-type memory (302) as a respective page therein, and the header of a page stored in memory is detected (303) prior to being pre-read therefrom. The detected header is read from memory a second time and the page data is read from memory at a time in accordance with certain data included in the pre-read header. The page data is decoded and supplied as an output to be combined with the video signal.