# To do metric test for imported .nrrd images

**URL:** https://discourse.slicer.org/t/to-do-metric-test-for-imported-nrrd-images/8836
**Category:** Support
**Created:** [October 18, 2019, 5:16pm UTC](https://discourse.slicer.org/t/to-do-metric-test-for-imported-nrrd-images/8836 "2019-10-18T17:16:13Z")
**Posts on this page:** 9
**Page:** 1

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### Author: ![HariES](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/haries/32/6045_2.png) [@HariES](https://discourse.slicer.org/u/HariES)
#### Post date: [October 18, 2019, 5:16pm UTC](https://discourse.slicer.org/t/to-do-metric-test-for-imported-nrrd-images/8836/1 "2019-10-18T17:16:13Z")

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The loaded .nrrd files not appeared in the moving and fixed image list for metric test module. How to get those in the list.

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### Author: ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [October 18, 2019, 5:50pm UTC](https://discourse.slicer.org/t/to-do-metric-test-for-imported-nrrd-images/8836/2 "2019-10-18T17:50:13Z")

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Which exact module you are trying to use (name of extension and module name)?  
Is there a chance that the nrrd file contains tensor or vector data (time sequence, color, diffusion image…)?

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### Author: ![HariES](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/haries/32/6045_2.png) [@HariES](https://discourse.slicer.org/u/HariES)
#### Post date: [October 19, 2019, 8:34am UTC](https://discourse.slicer.org/t/to-do-metric-test-for-imported-nrrd-images/8836/3 "2019-10-19T08:34:48Z")

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It is loaded as FSPGR Bravo 1.4mm-as DWI Volume. Is there any problem if it contains vector data.

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### Author: ![HariES](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/haries/32/6045_2.png) [@HariES](https://discourse.slicer.org/u/HariES)
#### Post date: [October 19, 2019, 4:14pm UTC](https://discourse.slicer.org/t/to-do-metric-test-for-imported-nrrd-images/8836/4 "2019-10-19T16:14:23Z")

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Registration–Metric Test

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### Author: ![HariES](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/haries/32/6045_2.png) [@HariES](https://discourse.slicer.org/u/HariES)
#### Post date: [October 22, 2019, 9:10am UTC](https://discourse.slicer.org/t/to-do-metric-test-for-imported-nrrd-images/8836/5 "2019-10-22T09:10:08Z")

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I have converted Fiesta and SPGR images using DWIconvert into .nrrd files and it is stored as DWI file. I applied Transforms and it has stored as new transform and new displacement file. Once I open to do metric test in General registration I could see only displacement file which is stored in convert section of Transform module. I cannot see any of nrrd original file in the list of moving and fixed image. How to do metric test for these images.

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### Author: ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [October 22, 2019, 1:25pm UTC](https://discourse.slicer.org/t/to-do-metric-test-for-imported-nrrd-images/8836/6 "2019-10-22T13:25:17Z")

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> [@HariES](#):
>
> Is there any problem if it contains vector data.

Yes, it is. Metric test module only accepts scalar images, not vector or tensor images. You can use “Vector to scalar volume” to choose a scalar component of a vector or tensor image and analyze the metric on that image.

What is your overall goal? What information do you expect from metric test will give you?

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<div class="post-metadata">

### Author: ![HariES](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/haries/32/6045_2.png) [@HariES](https://discourse.slicer.org/u/HariES)
#### Post date: [October 23, 2019, 2:04am UTC](https://discourse.slicer.org/t/to-do-metric-test-for-imported-nrrd-images/8836/7 "2019-10-23T02:04:46Z")

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I would like to see metric scoring with and without applying scaling factor in transform to study the mri images.

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### Author: ![HariES](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/haries/32/6045_2.png) [@HariES](https://discourse.slicer.org/u/HariES)
#### Post date: [October 23, 2019, 2:28am UTC](https://discourse.slicer.org/t/to-do-metric-test-for-imported-nrrd-images/8836/8 "2019-10-23T02:28:05Z")

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While converting I did not select any of Advanced Conversion Parameters to give scalar image. Any how the image is not having vector quantity since image is not dwi or dti image.

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### Author: ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [October 23, 2019, 4:40am UTC](https://discourse.slicer.org/t/to-do-metric-test-for-imported-nrrd-images/8836/9 "2019-10-23T04:40:28Z")

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> [@HariES](#):
>
> I would like to see metric scoring with and without applying scaling factor in transform to study the mri images.

Scoring of what metric? What scaling factor: spatial or intensity?

> [@HariES](#):
>
> While converting I did not select any of Advanced Conversion Parameters to give scalar image. Any how the image is not having vector quantity since image is not dwi or dti image.

There are no “Advanced Conversion Parameters” in “Vector to Scalar Volume” module. Which module did you use?  
Is your input volume type scalar or vector (Volumes module / Volume information / Volume type)?
