Directional filters applied to prefiltered imput image pyramids strike a good balance between fast computation and sharp, alias-free images, and are widely used for texture mapping and image warping. However, most published methods use implicit conversions between discrete and continuous images. This causes two flaws: 1) an input reconstruction filter is missing, causing unpredictable warp-dependent distortions and aliasing artifacts, and 2) address calculations are needlessly complex and inflexible. By including this filter we find a simpler, more accurate, and more general implementation of filtering for texture maps and image warping that can use any desired filter kernel. Effects of cascaded filters in image pyramids are also briefly discussed
