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Re: Faster image median filtering [message #76773 is a reply to message #76753] Sun, 03 July 2011 06:54 Go to previous message
Deckard++; is currently offline  Deckard++;
Messages: 11
Registered: March 2010
Junior Member
On Jun 25, 12:33 am, wlandsman <wlands...@gmail.com> wrote:
> I think suspect that the IDL implementation of MEDIAN is reasonably optimal (e.g. using a rolling window).  In the ancient days of IDL, MEDIAN() only worked on byte data, and I used to use a CALL_EXTERNAL to a C program for float data.    But when support for floating data in MEDIAN was added, it was definitely faster than my CALL_EXTERNAL setup.
>
> Having said that you might look at scaling your data to byte.    The MEDIAN() is the midpoint of ordered data , and the order should be maintained after byte scaling (except that resolution is lost, so some nonequal values become equal).      And MEDIAN is *much* faster on byte data.
>
> --Wayne

Hi Wayne,

scaling my data to byte is not possible I think, but thanks for the
tip.

-- Arthur;
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