Annular Region of Interest

[Graham Arden]

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

Thanks
Graham

[Wayne Rasband]

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.txt

that uses both methods.

When creating elliptical selections, you can force them to be circular  
by holding down the shift key.

-wayne

[dscho]

Hi,

On Sat, 25 Jul 2009, Wayne Rasband wrote:

> On Jul 24, 2009, at 6:30 AM, Graham Arden wrote:
>
> >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.

In many Linux setups, Alt+Drag moves the Window (which is especially
useful on small screens such as Netbook screens).  But you can still use
this feature: just do Ctrl+Alt+Drag.

Ciao,
Dscho

[Gabriel Landini]

On Sunday 26 July 2009, Johannes Schindelin wrote:
> In many Linux setups, Alt+Drag moves the Window (which is especially
> useful on small screens such as Netbook screens).  But you can still use
> this feature: just do Ctrl+Alt+Drag.

Or if you want to keep the same behaviour as in the other platforms, one can
also change the which key  + Drag moves the windows around.

In KDE, there is a setting to choose the alternative Meta key (which in PC
keybaords is sometimes labelled as the "Windows key"). I presume that this can
be done in Gnome too, but do not know how as I use KDE.

Cheers

Gabriel

[Graham Arden]

Wayne Rasband wrote:

>
> 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.txt
>
> that uses both methods.
>
> When creating elliptical selections, you can force them to be circular
> by holding down the shift key.
>
> -wayne

Thanks Wayne for your reply., and also Johannes and Gabriel for their
helpful points.

Graham