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Figure 10.13. A comparison of the standard implementation and the separable implementation of the bi-
lateral filter.
The results from this version of the algorithm are significantly faster than the brute
force method. In this case, the resulting image quality is similar to what it would have been
and does not produce objectionable artifacts in the output image. Figure 10.13 shows a
sample image with both the result of the original filter and the approximated result from
the separable implementation in Figure 10.13.
10.3.3 Conclusion
The bilateral filter is a very important tool to have in any image processing library. Its abil-
ity to perform a blurring operation that mostly preserves strong edges makes it quite ver-
satile. It has applications in post-processing, with a particularly strong case for being used
to smooth the results of stochastic, or randomized, sampling techniques. While the brute
force implementation produces a slightly higher image quality result, by use the separable
filter techniques, we can gain a big performance advantage and perhaps even use larger
filter sizes, because of the computational savings.