[Insight-users] about gaussian filter

[liu jianfei]

hi

   I used itkrecussivegaussiangradientmagnitude to compute the
magnitude of a 3D volume. I tried to set the deviation as 5, 10, and
20. I found that the magnitude of the image border was very large even
it's the background voxel. Since the image is first convolved with the
gaussian filter, can someone tell me how many voxels are used to
integrate the convolution. As far as I know, it's usually controlled
by the decay of the gaussian function, for example, it could be one
sigma (deviation), two, etc. Can someone tell me what's the time of
sigma? Thanks


   have a nice day!