Fast approximation of trilateral filter for tone mapping using a signal processing approach

In this paper, we present a novel fast approximation of the trilateral filter for high dynamic range (HDR) image tone mapping using a signal processing approach. Our fast trilateral filter-based tone-mapping algorithms are about 15–25 times faster than the existing one in Choudhury and Tumblin [The trilateral filter for high contrast images and meshes, in: Eurographics Symposium on Rendering ’03, 2003, pp. 186–196]. The novel tone-mapping algorithm for HDR images is presented based on the fast approximation of the gradient bilateral filter and the down-sampling strategy of computing the titling angle image. We show the comparison results with the fast approximation of the trilateral filter using full-kernel, truncated-kernel, piecewise-kernel, separable-kernel, respectively. The proposed approach is suitable for fast HDR image tone-mapping, and the experimental results show satisfactory performancce.