Hi Donald @jdtournier,
Thanks for your comments. Two further questions.
1, The unit for the extent is voxel, not mm. so if I have different resolution in x, y,z, I should give different number in each dimension. for example, if my voxel size is 1 x1 x 2, I should assign the extent as 9x9x5 to make a 10mm x10mm x 10mm windows. Am i right?
2, I have two runs data which were collected in different sessions. The parameters for the two runs is totally the same, but they are not aligned in space. If i want to combine them together to do denoise, What is the best option for me? can i directly concate them without do alignment ? The mannual told us: don’t do anything before dwidenoise.