[HtoA] Denoising light group AVOs with noice


To use the Arnold Denoiser (noice) on light groups, you need to have variance AOVs for the light group AOVs.

There are two ways to associate a variance AOV with a light group AOV.

  • Use the same light path expression (LPE) for both the light group AOV and the variance AOV.

    For example, the “red” and “red_variance” AOVs use the same LPE: C.*<L.'red'>
  • Use the same name for both AOVs, but give the variance AOV a different layer name.

    For example, suppose you give both AOVs the name “RGBA_green”. Then give the variance AOV a different layer name, like “RGB_variance_green”

Use the same light path expression (LPE) for both the light group AOV and the variance AOV.

Give the light group and variance AOVs the same name, but different layer names

Then to denoise the AOVs:

noice -i "light_group_denoise.0001.exr" -o C:\temp\denoised.exr -pr 3 -sr 3 -l red -l RGBA_green
noice 7.1.1.0 [72784a51] - the Arnold denoiser
Using 8 threads.
Loading images...
Loading file "light_group_denoise.0001.exr".
Using feature AOV 'denoise_albedo' with filter 'gaussian_filter'
Using feature AOV 'N' with filter 'gaussian_filter'
Using feature AOV 'Z' with filter 'gaussian_filter'
Working with 1 frame at 1280x720
Will denoise AOV "RGBA", using associated variance
   Output file will be "C:\temp\denoised.exr"
Will denoise AOV "RGBA_green", using associated variance
   Output file will be "C:\temp\denoised.exr"
Will denoise AOV "red", using associated variance
   Output file will be "C:\temp\denoised.exr"
Start denoising (patch radius 3, search radius 3, variance 0.5)
Denoising RGBA
Denoising RGBA_green
Denoising red
Finished denoising
Saving image C:\temp\denoised.exr (1280 x 720 x 12)

Add -irgba to that if you want to skip denoising the beauty. Note that with -irgba. the beauty AOV won’t be copied to the output file. Only the denoised AOVs go the output file.

All the AOV, LPE, and layer information that you set up in HtoA goes into EXR metadata.
noice uses that metadata to find the variance AOVs for each AOV. The association may be through the AOVs having the same name, or the AOVs using the same explicit LPE.

[MtoA] Denoising AOVs with the Arnold Denoiser


To denoise AOVs, you need to add variance AOVs:

  1. Enable Output Denoising AOVs
  2. Add a new output driver to the AOVs, and set the filter to variance
  3. Tell noice to denoise the AOVs: enter the AOV names in the Light Group AOVs text box (or, if you’re using the command-line, add -l flags for each AOV)

When you denoise the AOVs, you’ll see something like this in the Arnold Denoiser log:

C:\Program Files\Autodesk\Arnold\maya2020\bin\noice -i C:/project/images/denoiser_test.0002.exr -o C:/project/images/denoiser_test.0002_denoised.exr -ef 0 -sr 9 -pr 3 -v 0.5 -l diffuse -l direct -l indirect -l specular 

Denoising image C:/project/images/denoiser_test.0002.exr 
------------------------ (1/1)
noice 6.2.0.1 [903992ac] - the Arnold denoiser
Using 48 threads.
Loading images...
Loading file "C:/project/images/denoiser_test.0002.exr".
Using feature AOV 'diffuse_albedo' with filter 'gaussian_filter'
Using feature AOV 'N' with filter 'gaussian_filter'
Using feature AOV 'Z' with filter 'gaussian_filter'
Working with 1 frame at 960x540
Will denoise AOV "RGBA", using associated variance
   Output file will be "C:/project/images/denoiser_test.0002_denoised.exr"
Will denoise AOV "diffuse", using associated variance
   Output file will be "C:/project/images/denoiser_test.0002_denoised.exr"
Will denoise AOV "direct", using associated variance
   Output file will be "C:/project/images/denoiser_test.0002_denoised.exr"
Will denoise AOV "indirect", using associated variance
   Output file will be "C:/project/images/denoiser_test.0002_denoised.exr"
Will denoise AOV "specular", using associated variance
   Output file will be "C:/project/images/denoiser_test.0002_denoised.exr"
Start denoising (patch radius 3, search radius 9, variance 0.5)
Denoising RGBA
Denoising diffuse
Denoising direct
Denoising indirect
Denoising specular
Finished denoising
Saving image C:/project/images/denoiser_test.0002_denoised.exr (960 x 540 x 16)

[MAXtoA] Denoising AOVs with noice


First, set up your AOVs like this:

Then run noice like this:


set IMAGES="C:\Users\Stephen Blair\Documents\3ds Max 2020\renderoutput\denoiseme"

set ARNOLD_BIN=S:\solidangle\arnold\Arnold-6.0.2.0-windows\bin

%ARNOLD_BIN%\noice ^
-ef 2 -sr 2 -pr 2 -v 0.5 ^
-i %IMAGES%/AOVs0003.exr ^
-i %IMAGES%/variance0003.exr ^
-l diffuse ^
-l specular ^
-o %IMAGES%/denoised_AOVs0003.exr 

The AOVs and variance AOVs are in separate EXRs
That’s necessary to be able to have different filters for the same AOV in MAXtoA

Tip: In the Windows command prompt, you can use ^ (Shift + 6) character to indicate line continuation, and break long commands into multiple lines. You can also use ^ in in a batch file.