Re: speed and ROIs

Posted by Gabriel Landini on Jul 07, 2017; 8:39am
URL: http://imagej.273.s1.nabble.com/speed-and-ROIs-tp5019036p5019037.html

On Friday, 7 July 2017 08:05:19 BST you wrote:
> I am trying to speed up a macro that includes working repeatedly with a
> large stack.
 I assumed that if I operated on a selection and ran a filter,
> that the filter would only operate on the selection and would therefore be
> faster than using the whole stack.
> However when I checked the timings using they were almost identical.
>
> While it is reasonable that a selection only limits the volume operate on,
> it would be helpful if this translated into an increase in  the speed

It is twice as fast in my machine when the image is larger (e.g. 1256x1256).
I seem to remember that some filtering in IJ is done in multiple threads. Could
that make a difference?
Cheers

Gabriel

--
ImageJ mailing list: http://imagej.nih.gov/ij/list.html