https://www.posersoftware.com/documentation/12/index.htm#t=Poser_Reference_Manual%2FRendering%2FSuperFly%2FApplying_Post_Effects_to_Renders.htm%23h&rhsearch=denoise

Obviously Poser uses Intel's Denoiser.

But all denoisers worth mentioning are publicly available (Intel's at Github as open source, NVidia provides its own SDK which is also basically freely available). The advantage of Intel's denoiser (and probably the reason why Bondware doesn't use NVidia) is that - unlike NVidia's software - it can be used with CPU only.

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