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Hi Mark,

I seem to have a problem applying the COV shift to some registered images.
I am registering a 250x196x250mm volume to the 182x218x182mm standard
brain - so I have added the calculated FOV offsets to the last column's
x,y,z translation entries (34,-11,34mm respectively). After appplying the
modified mat file to the original image, it is still far from being
centred in the image. Am I missing something?

One clue might be that the registered image after the initial
registrations step does not seem to follow the rule you give of (0,0,0)
being the origin voxel. In this image, it is only the "upper" and "right"-
most parts of the brain that are visible and they are both lodged into
this lower left corner.

Thanks,

Gaby

On Mon, 22 Nov 2004 08:37:04 +0000, Mark Jenkinson <[log in to unmask]>
wrote:

>Hi Gaby,
>
>Sorry not to reply sooner.
>We don't have any scripts written to do this FOV correction
>as we've never used it ourselves.  However, all you need to
>do is extract the FOV difference (use avwhd to get the relevant
>sizes) and add/subtract half of this from the last column in
>the registration matrix.
>
>You could also pad if you like, but the above method is
>probably easier.
>
>All the best,
>        Mark
>
>
>
>On 16 Nov 2004, at 06:21, Gaby Pell wrote:
>
>> Hi Mark,
>>
>> Is there anyway to script this process for registration on multiple
>> volumes?
>> Another registration option I guess would be take the small FOV
>> reference
>> image and pad it in such a way as to keep the same voxel size but
>> increase
>> the FOV? Is this a sensible approach?
>>
>> Thanks,
>>
>> Gaby