Nrrd conversion error

when I try to convert dti image to .nrrd i 3Dslicer. i get this error.

terminate called after throwing an instance of 'slicer_itk::ExceptionObject'

what(): /work/Stable/Slicer-0-build/BRAINSTools/DWIConvert/DWIConvertLib.cxx:97:

ITK ERROR: Exception creating converter

itk::ExceptionObject (0x55cce21ae0d0)

Location: "unknown"

File: /work/Stable/Slicer-0-build/BRAINSTools/DWIConvert/DWIConverter.cxx

Line: 292

Description: ITK ERROR: number of Gradients doesn't match number of volumes:16 != 1

I’m new to this filed.does anyone knows how to deal with this?

Hi @Pranali_1 and welcome to neurostars!

I think we’d need more information to help. But it sounds like you might be trying to convert a single-volume file (maybe a sbref, ADC, TRACE, FA, or other off the scanner image) using a full gradient table, which should only be associated with the full DWI.

Is there any more information you can give as to how you are doing the conversion and what files you are selecting?


thank you for reply, I’m converting IXI002-Guys-0828-DTI-00.nii.gz to .nrrd using slicer dwi convert. I’m using bvec.txt and bval.txt given in IXI DTI data . want to get a whole brain tract. Let me know why i’m getting this error

Hi @Pranali_1,

It is not clear what the file is from the filename alone. It is possible that it is just a single volume of the DTI image. If that’s the case, you would have to merge it with the other 15 volumes (e.g., with FSL’s fslmerge) to get the full 16 volume image, which would then match your bval/bvec.