# Registration Initialization

**URL:** https://discourse.itk.org/t/registration-initialization/2164
**Category:** Uncategorized
**Created:** [August 19, 2019, 4:47am UTC](https://discourse.itk.org/t/registration-initialization/2164 "2019-08-19T04:47:26Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![kekday](https://discourse.itk.org/user_avatar/discourse.itk.org/kekday/32/960_2.png) [@kekday](https://discourse.itk.org/u/kekday)
#### Post date: [August 19, 2019, 4:47am UTC](https://discourse.itk.org/t/registration-initialization/2164/1 "2019-08-19T04:47:26Z")

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Hi all,  
I am very new to ITK and I was looking at this [notebook](http://insightsoftwareconsortium.github.io/SimpleITK-Notebooks/Python_html/63_Registration_Initialization.html)  
More specifically I see the initialization was done using

> initial\_transform = sitk.CenteredTransformInitializer(fixed\_image,  
> moving\_image,  
> sitk.Euler3DTransform(),  
> sitk.CenteredTransformInitializerFilter.GEOMETRY)

How do I go about not using any specific intialization? i.e. using the identity matrix as the initialization?

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<div class="post-metadata">

### 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: [August 19, 2019, 1:06pm UTC](https://discourse.itk.org/t/registration-initialization/2164/2 "2019-08-19T13:06:28Z")

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Hello @kekday,

Welcome to ITK and SimpleITK!

When you want to use the identity transformation you just create the transformation:

```auto
initial_transform = sitk.Euler3DTransform()

```

I would highly recommend [setting the transformation center](https://itk.org/SimpleITKDoxygen/html/classitk_1_1simple_1_1Euler3DTransform.html#a1157ae30421247945edae7ff2d160ba3) so that the rotation is around the fixed image’s center and not the origin. This greatly improves numerical stability.