[ITK] Wrong RescaleIntercept (0028, 1052) when saving float images to DICOM?

[Matt McCormick]

Hi Markus,

DICOM support for float pixel type images is limited, so it
recommended to cast to short or unsigned short with
itk::RescaleIntensityImageFilter. Care needs to be taken or
RescaleIntercept and RescaleSlope. In general, upgrading to the latest
ITK is a good idea.

DICOM writing improvements are planned on this repository:

  https://github.com/KitwareMedical/ITKDICOM

Thanks,
Matt

On Wed, Jun 21, 2017 at 2:48 AM, Markus Gramer
<markus.gramer at kuleuven.be> wrote:
> Hi there,
>
> I'm relatively new to ITK and DICOM so maybe I am misunderstanding
> something.
>
> I am trying to save a Nifti image in DICOM format using the meta information
> of a reference DICOM image. This works quite well for most of my images.
> However, I have some issues with images of data type float: When I try to
> save those images with the ImageSeriesFileWriter the DICOM tags for
> RescaleIntercept and RescaleSlope are set during writing (i.e. they got
> overwritten when I tried to set them manually before). It seems to me,
> however, that the intercept that is set should be still divided by the slope
> to follow the DICOM definition for those tags i.e. "IV =
> (slope*SV)+Intercept" to receive the image value (IV) from the stored value
> (SV). Currently it seems as if the intercept and slope are calculated for
> "IV=slope*(SV+intercept)".
>
> Could anyone verify this?
>
> Best,
>
> Markus
>
> PS: I am using ITK version 4.9.
>
>
>
> _______________________________________________
> Community mailing list
> Community at itk.org
> http://public.kitware.com/mailman/listinfo/community
>