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Message-ID:  <v04011702b6a5ef1619fb@[137.187.230.154]>
Date:         Tue, 6 Feb 2001 10:18:29 -0800
Reply-To:     ImageJ Interest Group <[log in to unmask]>
Sender:       ImageJ Interest Group <[log in to unmask]>
From:         Wayne Rasband <[log in to unmask]>
Subject:      Re: CenterOfMass error when minThreshold==0
In-Reply-To:  <002f01c08f88$98411460$02000003@signup>

>Wayne,
>This may be a moot point but
>when  minThreshold==0 and a thresholded particle contains zero value pixels,
>measure will return a (0,0) CenterOfMass.
>This is particularly a problem when using CofM for tracking or
>otherwise drawing lines to join particle CofM's.
>Properly thresholded zero-pixel-valued particles will appear at origin
>causing erratic lines.

I added Greg's fix to v1.21o and it seems to work. The Center of Mass of
all zero selections is now the same as the centroid.

-wayne

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