The newimage convolve function (used by avwmaths++) takes the kernel
origin to be the central voxel of the kernel, so using an image with
even voxel dimensions will introduce a slight offset...
The convolve function contains some basic logic to determine what
(hopefully!) should be the fastest method to perform the convolution,
fft is one of the possible methods...
Matt
> Hi,
>
> I thought in "-kernel file" the word "file" has to replaced by the
> real
> filename, it is not clear in the documentation, that file is a
> keyword for
> avwmaths++. With your last answer I find my fault: "-kernel file
> MYFILE",
> now it works.
>
> But a warning occurs: Off_centre convolution being performed as
> kernel has
> even dimendions
>
> What does it mean? My kernelfile is isometric hamming 32x32x32
> normalized.
>
> Does use avwmaths++ use fft to perform the computation, it takes a
> long time.
>
> Joerg
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