Hi, Peer,
Thanks so much for you reply.
Now I understand the dim3 and dim4 stuff.
For my dataset.
(1), Yes, it is collected by Simens 3 T Trio;
(2), The parameter of DTI acquisition (I’ve no idea about it either, just used the old sequence from our lab), as written in method part, is 72 slices, voxel-size: 2mm isotropic, TR:9100 sm, TE:85 ms, number of direction: 64, diffusion weight:2, be-value1:0s/mm2, b-value 2: 1000s/mm2). I asked my colleagues, what I understand so far is that: one DTI scan is the baseline, the other is the real data, and we need to subtract the baseline from the real data when we analyse the data.
As I checked the link (Getting data into BIDS format), as well as this video: https://www.youtube.com/watch?v=O1kZAuR7E00.
I found it is related to our scanning sequence.
I compare the DTI information in the youtube video, the two scans, each has more than 1000 dicom files. but for our scanning, we have one scan with 4860 dicom files and one scan with 72 dicom files. The error was from the later scan.
As the error message was
The number of volumes in this scan does not match the number of volumes in the corresponding .bvec and .bval files.
So, I opened the .bvec and .bval files,
.bvec shows
0
0
0
.bval shows:
1000