Re: Specifying ROI based on grayscale values?

Posted by Pang, Zhengyu (GE Global Research) on Dec 17, 2007; 3:18am
URL: http://imagej.273.s1.nabble.com/Specifying-ROI-based-on-grayscale-values-tp3697744p3697746.html

Johannes,

Thanks for your help. It is very useful. Additional question, what is
the difference between create mask and create selection?  Are they same?

Thanks,

Zhengyu

-----Original Message-----
From: Johannes Schindelin [mailto:[hidden email]]
Sent: Friday, December 14, 2007 2:58 PM
To: Pang, Zhengyu (GE, Research)
Cc: [hidden email]
Subject: Re: Specifying ROI based on grayscale values?

Hi,

On Fri, 14 Dec 2007, Pang, Zhengyu (GE, Research) wrote:

> Is there anyway to specify ROI based on grayscale values?

Just use the threshold function (Image>Adjust>Threshold...) and then
turn the selected pixels into a selection (Edit>Selection>Create
Selection).

Hth,
Dscho