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1. Running Denoise Via RenderOutputDefine Script (Single Frame)

   Create a RenderOutDefine.
   Wire this node to the previous RenderOutputDefine node.
   Select script for the type, select primary for the scriptInput, and set the scriptCommand to the following:
   
   

   $RMANTREE/bin/denoise_batch -o /path/to/directory/for/denoised/images $INPUT

   
   
   

2. Running Denoise Via commandline (Crossframe or Single Frame)

   Render out your images with katana --batch or katana queue. Then run the following command 

   
   

   $RMANTREE/bin/denoise_batch -o /path/to/directory/for/denoised/images imagename.*.exr

   
   
   

3. Running Denoise UI (Crossframe or Single Frame)
   
   The PRMan 25 shelf has a script called RenderMan Denoiser. You can open this to select and denoise images that you have already rendered out
   
   
   

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