A recursive hardware implementation of FIR filters for high definition video processing
h(l,m,n) = h , ( W hdn) The function ht(n) is usually a finite impulse response (FIR) type filter. One of the reasons for choosing an FIR filter is to have a linear phase response. An FIR filter can be realized using the direct form, where the filter consists of frame stores, multipliers, and adders. Since a linear response is needed, the coefficients of the filter will be symmetric, so that the number of multipliers can be reduced by half. However, for the direct form the number of frame stores is equal to the order of the filter.