Hi,
I was handed an acquisition with the gradient directions listed at the bottom of the post. Most operations on the data result in a [ERROR] DWI volumes could not be classified into b-value shells; gradient encoding may not represent a HARDI sequence error, I thought I’d try extracting the b=1000 “shell”, but get this error:
dwiextract -force -shell 1000 dti.mif dti-b1000.mif
dwiextract: [WARNING] existing output files will be overwritten
dwiextract: [ERROR] DWI volumes could not be classified into b-value shells; gradient encoding may not represent a HARDI sequence
any suggestions on how I might extract something useful from the data?
-dan
b-values
mrinfo dti.mif -dwgrad
0 0 0 0
0.000171634 -0.999568 -0.0293747 200
-0.012155 -0.00602182 -0.999908 150
-0.999528 -0.018454 -0.0245807 150
0.700613 -0.713288 -0.0190032 350
0.708191 -0.00864206 -0.705969 350
-0.00419509 -0.714502 -0.699621 350
-0.00419509 0.714502 -0.699621 350
-0.700613 -0.713288 -0.0190032 350
-0.708191 -0.00864206 -0.705969 350
0.575013 -0.585446 -0.571501 500
0.575013 0.585446 -0.571501 500
-0.575013 -0.585446 -0.571501 500
-0.575013 0.585446 -0.571501 500
1.99504e-05 -0.99991 -0.0134092 700
-0.00302786 -0.00454752 -0.999985 650
-0.999885 -0.00911076 -0.0121446 650
0.891333 -0.453207 -0.0113085 850
0.895496 -0.00706024 -0.445014 850
0.443969 -0.895965 -0.011768 850
0.446344 -0.00489115 -0.894848 850
-0.0010585 -0.8972 -0.441622 850
-0.00215196 -0.452824 -0.891597 850
-0.00215196 0.452824 -0.891597 850
-0.0010585 0.8972 -0.441622 850
-0.443969 -0.895965 -0.011768 850
-0.446344 -0.00489115 -0.894848 850
-0.891333 -0.453207 -0.0113085 850
-0.895496 -0.00706024 -0.445014 850
0.406737 -0.414139 -0.814281 1000
0.406737 0.414139 -0.814281 1000
-0.406737 -0.414139 -0.814281 1000
-0.406737 0.414139 -0.814281 1000
0.815247 -0.414195 -0.404741 1000
0.815247 0.414195 -0.404741 1000
0.406132 -0.820023 -0.403261 1000
0.406132 0.820023 -0.403261 1000
-0.406132 -0.820023 -0.403261 1000
-0.406132 0.820023 -0.403261 1000
-0.815247 -0.414195 -0.404741 1000
-0.815247 0.414195 -0.404741 1000
0.704154 -0.70999 -0.00902211 1350
0.707641 -0.00482968 -0.706556 1300
-0.00105847 -0.710558 -0.703638 1350
-0.00105847 0.710558 -0.703638 1350
-0.704154 -0.70999 -0.00902211 1350
-0.707641 -0.00482968 -0.706556 1300
0.664876 -0.670223 -0.329759 1500
0.666062 -0.338407 -0.664712 1500
0.666062 0.338407 -0.664712 1500
0.664876 0.670223 -0.329759 1500
0.331795 -0.670502 -0.66358 1500
0.331795 0.670502 -0.66358 1500
-0.000658634 -0.999962 -0.00864213 1500
-0.00201742 -0.00403885 -0.99999 1500
-0.331795 -0.670502 -0.66358 1500
-0.331795 0.670502 -0.66358 1500
-0.664876 -0.670223 -0.329759 1500
-0.666062 -0.338407 -0.664712 1500
-0.666062 0.338407 -0.664712 1500
-0.664876 0.670223 -0.329759 1500
-0.999953 -0.00538644 -0.00807604 1500