Got it! Implemented it! Reduced the size to 1.2Gb. I guess I'll have to
live with that. Thanks!
Regards,
Glad
On 10/18/2016 12:09 PM, John Ashburner wrote:
> The bounding box encodes the lower and upper x y and z coordinates in
> MNI space (in mm).
>
> Best regards,
> -John
>
>
> On 18 October 2016 at 10:47, Paul Glad Mihai <[log in to unmask]
> <mailto:[log in to unmask]>> wrote:
>
> Hi John,
>
> Thanks for the quick reply.
>
> Because the template encompasses the whole head, while the functional
> runs only have a small slab of recorded voxels, new voxels are added, so
> the file sizes increases drastically.
>
> How can I find out the size of my bounding box? I think I would like to
> reduce it but don't know what the 2x3 matrix represents. Can I click on
> different parts of the image and select the boundary points that contain
> all of the image?
>
> Regards,
> Glad
>
> On 10/18/2016 11:30 AM, John Ashburner wrote:
> > It depends on the image dimensions and datatype. 16 bit images require
> > two bytes per voxel. Floating point images and 32 bit images require
> > four bytes per voxel (you can see the data types via the Display
> > button). Multiply the number of bytes per voxel by the number of voxels
> > (by multiplying the image dimensions together). The .nii files also
> > have a tiny header of 352 bytes to account for.
> >
> > If you want smaller spatially normalised images, you could change the
> > bounding box (and hence the image dimensions) for them. You could also
> > increase the size of the voxels so that fewer of them cover the same
> > field of view.
> >
> > Best regards,
> > -John
> >
> >
> >
> >
> > On 18 October 2016 at 10:10, Paul Glad Mihai <[log in to unmask] <mailto:[log in to unmask]>
> > <mailto:[log in to unmask] <mailto:[log in to unmask]>>> wrote:
> >
> > Dear subscribers,
> >
> > I was wondering why is there such a huge jump in the file size after I
> > normalize my functional data (1.1 mm isovoxel) using a created template
> > and corresponding flow field. The jump is from 246 MB to 3.2 GB -- a
> > 13-fold increase! Is this normal?
> >
> > Regards,
> > Glad
> > --
> > Paul Glad Mihai, PhD
> >
> > Independent Research Group "Neural Mechanisms of Human Communication"
> > Max Planck Institute for Human Cognitive and Brain Sciences
> > Stephanstraße 1A, 04103 Leipzig, Germany
> >
> > Phone: +49 (0) 341-9940-2478
> <tel:%2B49%20%280%29%20341-9940-2478>
> <tel:%2B49%20%280%29%20341-9940-2478>
> > E-mail: [log in to unmask] <mailto:[log in to unmask]>
> <mailto:[log in to unmask] <mailto:[log in to unmask]>>
> >
> >
>
> --
> Paul Glad Mihai, PhD
>
> Independent Research Group "Neural Mechanisms of Human Communication"
> Max Planck Institute for Human Cognitive and Brain Sciences
> Stephanstraße 1A, 04103 Leipzig, Germany
>
> Phone: +49 (0) 341-9940-2478 <tel:%2B49%20%280%29%20341-9940-2478>
> E-mail: [log in to unmask] <mailto:[log in to unmask]>
>
>
--
Paul Glad Mihai, PhD
Independent Research Group "Neural Mechanisms of Human Communication"
Max Planck Institute for Human Cognitive and Brain Sciences
Stephanstraße 1A, 04103 Leipzig, Germany
Phone: +49 (0) 341-9940-2478
E-mail: [log in to unmask]
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