
Intel Open Image Denoise: High-Performance Denoising Library for Ray Tracing - ingve
https://openimagedenoise.github.io/
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lsh
In a similar vein to de-noising realtime path tracing, Christoph Shied has an
interesting paper that describes an algorithm that steps around the problem:
[https://cg.ivd.kit.edu/atf.php](https://cg.ivd.kit.edu/atf.php)

and his Quake2 demos (which are _amazing_ ) have gotten a lot of attention on
youtube recently:
[https://www.youtube.com/channel/UCdyHpbF9SgV8uMIWu3oHgdg/vid...](https://www.youtube.com/channel/UCdyHpbF9SgV8uMIWu3oHgdg/videos)

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antoineMoPa
I sometimes wonder if it would be possible for CPUs to have, in addition to
their full speed cores, a small part dedicated to parallel tasks with
drastically lower speed, but a very high number of cores. Like a tiny graphics
card, but with an x86 architecture and less driver problems.

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jcranmer
So... Xeon Phi?

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antoineMoPa
Something like that, but with more cores and cheaper.

It looks like there are up to 64 cores in Xeon Phi at 1.5Ghz (price > $1000).
A Nvidia 1030 is still better with more than 300 cuda cores at 1.4GHz (price
~= $150). Not that I think that cuda cores and Xeon Phi cores can be compared,
but 64 is not that much at that price... What we'd need is dumber cores in
very high number. We don't need all fancy things that normal CPU cores have,
like virtualization.

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jcranmer
Note that Nvidia's core counts are misleading. To apply Nvidia's logic to Xeon
Phi, a 64-core Xeon Phi is really 512 cuda cores--each SIMD lane is counted as
an independent "Cuda core".

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wtallis
I wish we could talk about GPUs and similar architectures in terms of their
total FPU width—how many 32b or 64b floating point operations can be done per
clock— and as a secondary measure the number of independent instruction
streams that can be worked on in parallel. One provides a upper bound on the
arithmetic power of the chip and the other predicts how easy it will be to get
close to full utilization of those compute resources. Distilling an
architecture down to just one core count only guarantees that you can't
compare it against dissimilar architectures.

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nitrogen
Are these algorithms applicable to low light photography?

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AstralStorm
Approach yes, exact algorithms no.

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alkonaut
What is the difference that makes the algorithm not be applicable? Is it that
path tracing noise is "pure monte carlo noise" (I'm sure that has a better
term) so has nicer properties from photographic sensor noise (thermal noise
with various patterns etc)?

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BubRoss
There are two huge factors, the first even more potent than the second.

First, there is much more information per sample and per pixel. Normals,
depth, separate diffuse color, separate diffuse texture, first bounce normal,
first bounce position, etc. There is a technique that just uses color, but
uses histograms of all the samples within a pixel.

Second, for a video game you can accumulate samples temporally. Many of these
demos will use one sample per pixel, but filtering information can be kept on
every frame and reused to some degree.

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alkonaut
Oh I thought this operated on a 2D hdr image, without further info (I admit I
didn’t read the details).

If it can’t be used on a still I rendered 10 years ago with code that isn’t
around anymore then it’s clear it can be used on a photo either.

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rocky1138
For the example picture, it would be nice to have it also compared to a fully
raytraced image. I'd love to know how many rays it would take to be equivalent
to the denoised version.

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jadbox
Blender has a denoiser, but this looks def better. I wonder if it can be
integrated? Also, does this also work for AMD?

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swerner
I'm working on it:
[https://twitter.com/stefan_3d/status/1090607219975045120](https://twitter.com/stefan_3d/status/1090607219975045120)

It should work on any CPU with SSE4.2 support, which includes all modern AMD
CPUs.

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PavlikPaja
How does it work? Some of the examples (especially the crytek sponza one) seem
impossible.

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eklavya
Off topic: are there similar efforts for denoising audio? Any pointers
appreciated.

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dharma1
yes, this is an active area of study. You could check out
[https://people.xiph.org/~jm/demo/rnnoise/](https://people.xiph.org/~jm/demo/rnnoise/)

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eklavya
Sorry for the late reply, already tried it, not so good results.

