Beauty AOV / Cryptomatte material AOV


Arnold supports Cryptomatte, an ID matte creation tool created by Jonah Friedman. It creates ID mattes automatically with support for motion blur, transparency, and depth of field. Names, object namespaces, and material names can be used to organize ID mattes in the scene.

The following Cryptomatte AOVs are available under AOVs.

  • crypto_asset creates the same matte for all assets.
  • crypto_material creates a matte based on the assigned shader.
  • crypto_object creates a matte based on the object name.


Cryptomatte shader available in Shop> Arnold Vopnet

  • Create an OUT_AOV node and connect your AOV_writes into it.


  • Render the Cryptomatte AOVs to disk (as EXR).


  • Opening the EXR in a compositing package such as Nuke or Fusion shows the available Cryptomatte AOVs.



There is a limitation with the current Cryptomatte implementation, where object names are expected to follow the MtoA naming convention. A workaround is to manually set the "crypto_asset" string attribute on the geometry you want to belong to the same asset ID, that works.



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