[Insight-users] registration for tiled volume

[Rocky Rhodes]

Thanks.  I've already begun experimenting with just this procedure.  I
started out by having each block use the same image coordinate space.  I
selected the overlap region as the FixedImageRegion and set initial
parameters for the search to position the blocks approximately correct.
This seemed to give me reasonable results.

Then I tried using the MetaImage format to carry the consistent image
coordinates for the blocks.  With this information added, the registration
class does its job without me setting the FixedImageRegion parameter.
Should this still be set or is the registration framework smart enough to
only use the spatially overlapping region for its metric calculation?

The individual files I have from this device are smaller than I'd like.
What would be the most straightforward way to stitch them together into
larger blocks, once I've determined proper transformation information with
the registration classes?  And then I wonder if there would be any other
issues.  For instance, after stitching together the first two blocks, the
axis-aligned bounding box enclosing the two blocks may now contain some
voxels that are outside the coverage of either of the original blocks.  When
blending this new block with a third block, I need to make sure that only
the "full" voxels are blended with the third block.

Higher level classes for microscopy applications seem like a good idea to
me.  After I get a little experience with this first pass, maybe I can help
out with it.

	Rocky

> -----Original Message-----
> From: Luis Ibanez [mailto:luis.ibanez at kitware.com]
> Sent: Friday, September 24, 2004 10:50 AM
> To: Rocky Rhodes
> Cc: 'insight-users at itk.org'
> Subject: Re: [Insight-users] registration for tiled volume
> 
> 
> 
> Hi Rocky,
> 
> There is not an specific functionality in ITK for
> registering tiles of images. However, several users
> have already attempted this for microscopy and satelite
> images applications.
> 
> What you can do is to register the blocks by pairs
> using the registration framework described in the
> ItkSoftwareGuide.pdf and in the tutorials,  then
> iterate over the block pair combinations until
> convergence.
> 
> It probably makes sense to develop a higher level
> class that will do this for N1 x N2 x  ...Nn images,
> I would guess that people in microscopy will be happy
> to have such a class available.
> 
> Note that while you do the registration by pairs you
> may want to set the "FixedImageRegion" of the Metric
> to be just the region of overlap between one cube and
> the next.
> 
> It is extremely important that you make sure that the
> image cubes have each one consistent image origin
> coordinates and consistent pixel spacing values.
> 
> 
>   Please let us know if you have further questions.
> 
> 
>     Thanks
> 
> 
>        Luis
> 
> 
> ---------------------
> Rocky Rhodes wrote:
> 
> > I have a large volume data set that is composed of a number 
> of cubes that
> > overlap a bit.  I need to combine these pieces into a 
> whole.  Are the itk
> > registration classes appropriate for this?  I scanned the 
> registration
> > chapter in the book and didn't see anything that directly supported
> > overlapping tiles.
> > 
> > Thanks for the help.
> > 
> > 	Rocky
> > 
> > _______________________________________________
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> > Insight-users at itk.org
> > http://www.itk.org/mailman/listinfo/insight-users
> > 
> 
> 
> 
> 
>