Hi John
> It crashes because your images appear to be in different orientations
> according to the matrices in the headers. There is a little flexibility
> in deciding whether images are aligned (to allow for rounding errors),
> and I figured that 1e-4 would be reasonable for this (it is greater than
> eps(single(512)) - so should deal with the single-precision tolerance
> for representing the elements of the affine transform matrix). How
> similar are the matrices? Perhaps the images have been realigned - but
> not resliced?
>
thanks for the quick reply,
well actually I checked with Check Reg and images appeared to be
(visually) well aligned (tricks from the header file). Indeed you are
right, even if this was batched and that I do have the plot of the
realignment it appears in display that it hasn't been resliced ?? bizarre
well I'll just reprocess the images ..
thanks (this was something I should have come up first before going into
crazy details)
best
cyril
> Best regards,
> -John
>
> -----Original Message-----
> From: SPM (Statistical Parametric Mapping) [mailto:[log in to unmask]]
> On Behalf Of cyril pernet
> Sent: Thursday, September 06, 2007 2:08 PM
> To: [log in to unmask]
> Subject: [SPM] error spm_orientation at 32
>
> Hi there,
>
> while loading a set of EPI images for a 1st level analysis I got a
> 'funny' error using ==> spm_check_orientations at 32
> for sure my images are correct, using a loop across my images with
> V.dim(1) == V.dim(i) I got my sum = all my images, ie all dimensions are
>
> equals, but still spm_check_orientations gives me an error ; note they
> are also all well oriented (spm_orientation ok).
>
> the only remaining thing is reshape(cat(3,V.mat),[16,numel(V)]) is >
> 1e-4
> and this is where spm_check_orientations crashes but I have no idea why
> this limit ??
> any help would be greatly appreciated
>
> cyril
>
>
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