Sharpening the response of the (9,7) filter pair by multiple use of half-band subfilter

Sharpening the response of the (9,7) biorthogonal filter pair by multiple use of a short half-band subfilter is presented. The process involves sharpening a half-band filter with several half-band subfilters and exploiting associated successive transformations. The realization for the derived filter pair is by plugging a systolic array of short half-band subfilters into each stage ladder of an underlying biorthogonal filter pair. The advantages of the resulting sharp biorthogonal filter pairs are their ease of design, their reduction of complexity, their simplicity and regularity of realization, and their flexibility.