# About Image Orientation?

**URL:** <https://discourse.vtk.org/t/about-image-orientation/10771>\
**Category:** Development\
**Tags:** code, proposal\
**Created:** [February 23, 2023, 10:17am UTC](https://discourse.vtk.org/t/about-image-orientation/10771 "2023-02-23T10:17:02Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![wulicheng](https://discourse.vtk.org/user_avatar/discourse.vtk.org/wulicheng/32/1990_2.png) [@wulicheng](https://discourse.vtk.org/u/wulicheng)\
**Post date:** [February 23, 2023, 10:17am UTC](https://discourse.vtk.org/t/about-image-orientation/10771/1 "2023-02-23T10:17:02Z")

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I have a series of dicom files,when i read that series of dicom files with vtkImageReader, it display like flows:

 ![无标题](https://discourse.vtk.org/uploads/default/original/2X/0/0ccace3501d09b1dfb0ee4bd1fc96da650ac2983.png)  
But i want to display it face to screen and like this:  
 ![图片](https://discourse.vtk.org/uploads/default/original/2X/7/716f54a94cc884de7d3a8dfd9b808cca9e2dcdc3.png)

Do someone know how to compute the orientation using the tag and then show it.

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**Author:** ![dgobbi](https://discourse.vtk.org/user_avatar/discourse.vtk.org/dgobbi/32/18_2.png) [@dgobbi](https://discourse.vtk.org/u/dgobbi)\
**Post date:** [February 23, 2023, 2:18pm UTC](https://discourse.vtk.org/t/about-image-orientation/10771/2 "2023-02-23T14:18:51Z")

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If you are doing a lot of work with DICOM, then you can build the [vtk-dicom](https://github.com/dgobbi/vtk-dicom) package and use the [vtkDICOMReader](http://dgobbi.github.io/vtk-dicom/doc/api/classvtkDICOMReader.html). It has many more features than the [vtkDICOMImageReader](https://vtk.org/doc/nightly/html/classvtkDICOMImageReader.html) that is built into VTK.

For orientation, it has a method `GetPatientMatrix()` that returns a `vtkMatrix4x4`. This matrix can be applied to the actor (in your case, a `vtkVolume`?) with the method `SetUserMatrix()` to put it into DICOM Patient Coordinates. In this coordinate system, you can point the camera in the direction (0, 1, 0) to get a front view.