Hi,
Can someone tell me what the conventions are for the gradient directions in the .dts file? Are they in image coordinates (i.e. 1 0 0 means diffusion along the fastest axis in the data, 0 0 1 along the slowest), or in ITK coordinates (which I guess is LPS-positive, meaning 0.707 0.707 0 points between left and posterior), or something else?
Also, what is the effect of AffineTransform in the .dts file? I understand it has an effect, as I've been playing around with the values, but wasn't sure of its intended use. Does every point in the calculated fibers merely get multiplied by that transform before it is saved? If so, is 1 0 0 0 1 0 0 0 1 0 0 0 the equivalent of a no-op? (I assume DTI Track reads and uses orientation info from the input image file)
Thank you!
-syam