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Rajesh
Posts:
26
Registered:
2/22/10


Re: subpixel shifting of a matrix
Posted:
Feb 26, 2010 5:24 AM


> You can extrapolate with zeros or any other desired value using the EXTRAPVAL option. >
I already tried that but the background in the image has a certain mean and sd as would be the case for an image. moreover replacing it with a certain constant requires a knowledge of the actual pixl value of the background which will have to be obtained from the image itself by picking a certain area or certain pixel of the background in the image but that, i guess, would take further time (or no?) since i am handling mutliple images in a loop while translatng them.
Also, replacing them with a constant might give artefacts in futue reconstructions (rings in CT images) > > Result=zeros(size(Image)); > Result(1:end+1k,1:end+1j)=Image(k:end,j:end);
Thanks for this as well.
> If the object is completely surrounded by background values of zero, I don't see what's challenging about that. What I've outlined above will work.
thanks (appologies if this amounts to hijacking the original thrd)



