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Re: efficient kernel or masking algorithm ?
WOW, I need to look at these equations over about a dozen times to see what
is going on ?
I have been struggling with the variance of an nxn window of data, INCLUDING
;mean of the neighboring pixels (including central)
;square deviation from that mean
;variance of an nxn window of data, INCLUDING central pixel
This doesn't seem correct with test samples ? (Only difference is mean and
division by n^2-1 ??)
J.D. Smith <email@example.com> wrote in message
> Oh my this is a common topic lately. See my recent posts in a thread
> with title "Array Manipulations". Here's the good stuff:
> ; the nxn window total
> ; the nxn window total not including central pixel
> ; the mean of the neighboring pixels (excluding central)
> ; the square deviation from that mean
> ; the variance of an nxn window of data, excluding central pixel
> Take a look at the "EDGE*" keywords too, if you care about what happens
> near the borders.
> J.D. Smith | WORK: (607) 255-6263
> Cornell Dept. of Astronomy | (607) 255-5842
> 304 Space Sciences Bldg. | FAX: (607) 255-5875
> Ithaca, NY 14853 |