Shrinking large Vdb files

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What are people's techniques for shrinking or dealing with large VDB files? We are hitting 5GB per frame with just density + velocity, trying to use VolumeCompress to bring it down to 16 bit seems to have no effect on VDBs. Thinking of masking the velocity with the density.

Thanks!
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You may want to look into controlling the voxel count before you hit the compress.
Using Houdini Indie 20.5
Windows 11 64GB Ryzen 16 core.
nVidia 3060RTX 12BG RAM.
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thanks but I'm looking for a technical answer to maintain detail i.e. dithering, vdb compression, discretization of the volumes etc.
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VDB don't support any quantization schemes like that, that I know of. All you can do is try to limit number of active voxels, and/or enable 16bit (use primitive sop.)
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thanks, I'll have to try that - removing the velocities has reduced it to ~0.5GB. It's a classic far away smoke that then hits the camera. Needs to be rendered with motionblur in Vray though.
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Deactivate the vel field using density as a mask. That way you only get velocity where you need it for rendering.
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@Skybar - I'm failing terribly at deactivating. Can anyone fix my example please.
Thx!

Attachments:
ActiveVoxels.hiplc (613.0 KB)

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