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If your pipeline does not support multichannel EXR, you can use $RMANTREE/bin/exrmerge to combine the AOVs into a multichannel EXR.

Then use this merged multichannel EXR for the denoise utility.

Note that each AOV's type should be set to "raw" because this preserves the channel name in the EXR which the denoise utility will look for. Combined EXR using Katana's RenderOutputDefine's merge will not work with the denoise utility.

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