Improve image contrast windowing in DICOM output

[tomaroberts]

Currently, when generating different types of DICOM (MRI, CT, different scanners, etc.) the intensity values/windowing in the output DICOM can be incorrect, e.g.:

Output DICOM contrast from input CT NIfTI dataset:

Some modalities are working, others are not.

TODO:

• improve the method of interpreting the NIfTI voxel values and correctly setting the contrast/windowing/slope tags in the DICOM files.

[tomaroberts]

Reminder... running:

• nii2dcm input.nii.gz output seems to produce DICOMs that look correct when opened in MITK Workbench
• nii2dcm input.nii.gz output -d SVR seems to produce DICOMs that look correct when opened in ITK Snap

Tried this with both CT and MRI DICOMs... something in how different programs interpret the DICOMs, but also some inconsistency in the nii2dcm Dicom/DicomMRISVR classes

[yuankaiWang]

the dicom file which has converted shows a big different in CT value. the window range is like 6,7 times larger

[tomaroberts]

Tested again today on generic CT image and this is still a problem.

Need to resolve such that running nii2dcm input.nii.gz output -d MR, nii2dcm input.nii.gz output -d CT, etc. outputs a DICOM dataset with reasonable contrast.

Currently tailored to specifically to SVRTK NIfTI files.