MULTISTAGE SDTV HDTV SCANNING RATE CONVERTERS

SDTV/HDTV conversion has several applications of current interest, suc h as pyramidal coding for simultaneous SDTV and HDTV output, HDTV disp lay of SDTV signals, and SDTV display of HDTV signals. The effectivene ss of multistage filters in this application is established, The desig n of the filters to use in these configurations is a delicate issue, s ince it has to balance several, and sometimes conflicting, requirement s. The design objectives depend on the specific application, and are u ltimately targeted to the visual rendition of the system. These object ives do not fit traditional design specs and call for provisions of vi sual significance in both the frequency domain and the spatio-temporal domain. This work reports on the findings of some systematic research on this field.