Re: Annular Region of Interest
Posted by
Wayne Rasband on
Jul 25, 2009; 9:38pm
URL: http://imagej.273.s1.nabble.com/Annular-Region-of-Interest-tp3691656p3691657.html
On Jul 24, 2009, at 6:30 AM, Graham Arden wrote:
> Hello
>
> Is it possible to produce annular ROI in imageJ. I have a number of
> nuclear medicine phantom images which consist of an area of high
> activity surrounding an area of low activity and I wsih to define an
> annular ROI to measure the maximum, minimum, mean and standard
> deviation of the counts in the hot and cold areas.
>
> Any suggestions would be gratefully received
You can create a ring-shaped selection by using the elliptical
selection tool twice, first to create the outer boundary and then,
with the alt key down, to create the inner boundary. You can also
create one by using the Edit>Selection>Make Band command. There is an
example macro at
http://rsbweb.nih.gov/ij/macros/examples/AnnularSelection.txtthat uses both methods.
When creating elliptical selections, you can force them to be circular
by holding down the shift key.
-wayne