Forums Technical Discussion VEX: Get Min/Max Values of a Texture (the Fastest Way?)

VEX: Get Min/Max Values of a Texture (the Fastest Way?)

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olivierth
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Hi!

I need to find the min and max value of a displacement texture. I was using a Detail Wrangle to go over each pixel but its a bit slow with 4K textures. Is there a trick to getting the min/max values faster (with less calculations)?

-Olivier
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animatrix_
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Hi,

The fastest method is likely to load the texture into COPs and use the Volume Reduce SOP. You have to split the volume into scalar volumes using the Volume Vector Split SOP as Volume Reduce SOP doesn't support collated volumes.

Attachments:
volumereduce.png (2.7 MB)

Senior FX TD @ Industrial Light & Magic
Get to the NEXT level in Houdini & VEX with Pragmatic VEX! [www.pragmatic-vfx.com] https://lnk.bio/animatrix [lnk.bio]
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tamte
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you can also use Statistics COP or Prefix Sum COP
Edited by tamte - April 21, 2025 17:28:18
Tomas Slancik
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olivierth
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Oh, I was avoiding 20.5 because of the slow startup + crashes. I guess I wont have a choice.

Thanks for the infos!

-Olivier
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tamte
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olivierth
I guess I wont have a choice.
You dont need 20.5 for Volume Reduce SOP
Tomas Slancik
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Framestore, NY
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