# Affine matrices (Insight format) with tag MatrixOffsetTransformBase\_double\_3\_3 cannot be loaded into Slicer anymore

**URL:** <https://discourse.slicer.org/t/affine-matrices-insight-format-with-tag-matrixoffsettransformbase-double-3-3-cannot-be-loaded-into-slicer-anymore/2302>\
**Category:** Support\
**Created:** [March 13, 2018, 11:20am UTC](https://discourse.slicer.org/t/affine-matrices-insight-format-with-tag-matrixoffsettransformbase-double-3-3-cannot-be-loaded-into-slicer-anymore/2302 "2018-03-13T11:20:57Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![mangotee](https://avatars.discourse-cdn.com/v4/letter/m/c57346/32.png) [@mangotee](https://discourse.slicer.org/u/mangotee)\
**Post date:** [March 13, 2018, 11:20am UTC](https://discourse.slicer.org/t/affine-matrices-insight-format-with-tag-matrixoffsettransformbase-double-3-3-cannot-be-loaded-into-slicer-anymore/2302/1 "2018-03-13T11:20:58Z")

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After running ANTs buildtemplateparallel.sh script to create a template from several of our MRI scans, we receive multiple pairs of linear-affine matrices (_.txt) and deformation fields (_.nii.gz) that I want to load into Slicer for visualization&sanity checking.  
Expected behaviour: drag&drop the .txt affine matrix file into Slicer, and the transform gets loaded.  
Actual behaviour: the matrix transformation tag is not recognized by Slicer, as described in the error log:  
“Could not create an instance of “MatrixOffsetTransformBase\_double\_3\_3”  
The usual cause of this error is not registering the transform with TransformFactory”.  
I have to manually change the tag “MatrixOffsetTransformBase\_double\_3\_3” to “AffineTransform\_double\_3\_3”, then it gets loaded correctly.

The full .txt content prior to the manual change is the following:  
#Insight Transform File V1.0  
#Transform 0  
Transform: MatrixOffsetTransformBase\_double\_3\_3  
Parameters: 1.128638506675143 -0.018901975572667252 0.003732574598088019 0.05839336218683332 0.9249441890918595 0.012912029188555302 -0.0007861952948720328 -0.09741033293018547 1.2857967364097567 3.45194891887621 -1.6884605061223075 8.428466991955123  
FixedParameters: -2.1885326956456645 -15.230008711557268 -15.255627879066756

Previously (Slicer versions \<4.8), I was able to load these files without error, now it doesn’t work anymore. Could you please advise?

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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:** [March 13, 2018, 12:08pm UTC](https://discourse.slicer.org/t/affine-matrices-insight-format-with-tag-matrixoffsettransformbase-double-3-3-cannot-be-loaded-into-slicer-anymore/2302/2 "2018-03-13T12:08:09Z")

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There were 1-2 days recently when this was broken in the nightly version. It should work well in the current nightly version.

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**Author:** ![jcfr](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/jcfr/32/17825_2.png) [@jcfr](https://discourse.slicer.org/u/jcfr)\
**Post date:** [March 13, 2018, 1:38pm UTC](https://discourse.slicer.org/t/affine-matrices-insight-format-with-tag-matrixoffsettransformbase-double-3-3-cannot-be-loaded-into-slicer-anymore/2302/3 "2018-03-13T13:38:19Z")

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> [@lassoan](#):
>
> There were 1-2 days recently when this was broken in the nightly version. It should work well in the current nightly version.

Indeed, commit [r27035](http://viewvc.slicer.org/viewvc.cgi/Slicer4?view=revision&revision=27035) fixed the regression