System and method for filter kernel interpolation for seamless mipmap filtering

摘要

There is provided a system and method for filter kernel interpolation for seamless mipmap filtering. There is provided a method of implementing a filter kernel interpolation for seamless filtering of transitions within a plurality of mipmaps derived from a base-image texture filtered using a prefilter, the method comprising choosing a filter kernel, determining a filter width for the filter kernel, selecting a first mipmap and a second mipmap from the plurality of mipmaps, applying interpolation on the filter kernel based on the prefilter, the first mipmap, and the second mipmap to generate an interpolated filter kernel, and applying the interpolated filter kernel to the first mipmap to generate a seamless filtered texture. Two alternative methods of interpolation are introduced, including filter kernel value interpolation and filter kernel position interpolation with x-lerping. By avoiding access to the second mipmap, greater efficiency and image quality can be achieved versus conventional interpolation.

主权项

1. A method of implementing a filter kernel interpolation for seamless filtering of transitions within a plurality of mipmaps derived from a base-image texture filtered using a prefilter, the method comprising:
determining a filter width in pixels for use with a filter kernel, the pixels corresponding to texels of the base-image texture; selecting a first mipmap and a second mipmap from the plurality of mipmaps wherein the first mipmap has a mipmap level based on the filter width, and the second mipmap has a mipmap level one higher than the first mipmap; applying interpolation on the filter kernel based on the prefilter, the first mipmap, and the second mipmap to generate an interpolated filter kernel, wherein applying the interpolation interpolates an index position of each texel in the first mipmap such that the index position of each texel in the first mipmap is moved, in the mipmap level of the first mipmap, from a center of the index position of each texel in the first mipmap towards a center of a corresponding texel in the second mipmap; and applying the interpolated filter kernel to the first mipmap, without applying the interpolated filter kernel to the second mipmap, to generate a filtered texture having a filtering of a transition between the first mipmap and the second mipmap.