A method of producing a plurality of filter kernels comprised of filter
coefficients for use in a sub-pixel rendering operation comprises
calculating a plurality of filter coefficients for each filter kernel by
dividing a spatial area of an input image that is overlapped by a portion
of a spatial rendering area by a total area of the spatial rendering area
using floating point arithmetic. The method further comprises multiplying
each filter coefficient by a divisor to produce a filter product such
that a sum of all filter products produces a filter sum that equals the
divisor. Then a binary search operation is performed to find a round off
point for the filter sum such that when each filter coefficient is
converted to an integer, a sum of the filter coefficients equals the
divisor. The filter coefficients are then converted to integers using the
round off point.