[Insight-users] mpi and itk

[David Fuentes]

Kevin,

many thanks for the reply, I'll look into the filters you mentioned and
dig up your old post.


I have an image processing algorithm that is pixel wise computationally
expensive and I want to break it up on several processes.
For transferring data back and forth I what to use Petsc's
structured grid infrastructure. 
Do you know if RegionOfInterestImageFilter, ExtractImageFilter, 
PasteImageFilter, etc...
copy the associated section of the pixel buffer of the full image into its
own local buffer? For example when doing an MPI send of a pixel buffer
associated with ExtractImageFilter are you sending the data from
the full image buffer and thus have to declare special MPI_Datatypes,
etc... to  MPI_Send with an offset?




df



On Thu, 22 Jan 2009, Kevin H. Hobbs wrote:

> On Wednesday 21 January 2009 21:46:36 David Fuentes wrote:
>> has anyone experimented with parallelizing  ITK image data
>> structures via MPI? How did you go about it?
>>
>
> Yes, I've tried some very simple steps. I split image regions. I've pasted
> pieces together, and sent pieces to other nodes. I posted what I did to the
> list but I can't remember when.
>
>> I'm thinking of partitioning the image with
>> RegionOfInterestImageFilter so that each processor
>> can own a subdomain of the image to process?
>>
>
> I used a modified image region splitter, ExtractImageFilter, and
> PasteImageFilter, but the same idea.
>
>>
>> not sure how to handle ghost element/pixels however...
>>
>
> With image regions it's easy enough to just add or subtract the number of
> border pixels to the region.  What happens next I suppose depends on the
> algorithm.
>
> What task are you trying to do?
>
> I've been dreaming about an MPI fast marching image filter.
>