# ITK ERROR: MattesMutualInformationImageToImageMetricv4(000001F33CCCA180): VirtualSampledPointSet must have 1 or more points.

**URL:** https://discourse.itk.org/t/itk-error-mattesmutualinformationimagetoimagemetricv4-000001f33ccca180-virtualsampledpointset-must-have-1-or-more-points/5611
**Category:** Engineering
**Tags:** registration
**Created:** [January 5, 2023, 3:16am UTC](https://discourse.itk.org/t/itk-error-mattesmutualinformationimagetoimagemetricv4-000001f33ccca180-virtualsampledpointset-must-have-1-or-more-points/5611 "2023-01-05T03:16:45Z")
**Posts on this page:** 1
**Showing post:** 5

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### Author: ![zivy](https://discourse.itk.org/user_avatar/discourse.itk.org/zivy/32/1726_2.png) [@zivy](https://discourse.itk.org/u/zivy)
#### Post date: [January 5, 2023, 1:49pm UTC](https://discourse.itk.org/t/itk-error-mattesmutualinformationimagetoimagemetricv4-000001f33ccca180-virtualsampledpointset-must-have-1-or-more-points/5611/5 "2023-01-05T13:49:43Z")

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Hello @ma1282029525,

Not sure if this is the case, but the combination of small\_mask + large\_image + random\_sampling can lead to this situation, see [this long discussion and possible work-arounds](https://discourse.itk.org/t/fixed-mask-not-working-as-expected/1238). It is not about 2D vs. 3D, simply in 3D the chances of this happening are higher.

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_[View the full topic](https://discourse.itk.org/t/itk-error-mattesmutualinformationimagetoimagemetricv4-000001f33ccca180-virtualsampledpointset-must-have-1-or-more-points/5611)._