measuring distances between circles

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measuring distances between circles

dfroelich
I would like to automate this task.  I am trying to measure the minimum distances between neighboring colonies on agar plates.  
So far: {macro:
threshold - to convert the images to a binary,
invert - white colonies on a black background,
distance map - intensity values (0-255) correspond to neighboring colony distance}
Line tool - draw lines (by hand) between neighboring colonies, then measure/record minimum intensity values.

Is there a way to replace that last step so that imageJ draws lines between adjoining colony's centroids and records their minimum intensities?
Thank you
Daniel Froelich
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Re: measuring distances between circles

karo03
Depending on the shape of your colonies possibly a slightly more  
geometrical approach is adequate:
- Threshold
- Measure colony features: Perimeter (for radius calculation) or  
Ferets Diameter and Center of Mass
- Generate Delaunay Triangulation (plugin) using the measured Centers  
of Mass and store results
   (Coordinates of the edges)
- Calculate Edge length minus the corresponding radii rspw. Diameter
For circular colonies it should work.
Regards
Karsten

Am 17.03.2009 um 18:47 schrieb dfroelich:

> I would like to automate this task.  I am trying to measure the  
> minimum
> distances between neighboring colonies on agar plates.
> So far: {macro:
> threshold - to convert the images to a binary,
> invert - white colonies on a black background,
> distance map - intensity values (0-255) correspond to neighboring  
> colony
> distance}
> Line tool - draw lines (by hand) between neighboring colonies, then
> measure/record minimum intensity values.
>
> Is there a way to replace that last step so that imageJ draws lines  
> between
> adjoining colony's centroids and records their minimum intensities?
> Thank you
> Daniel Froelich
> --
> View this message in context: http://n2.nabble.com/measuring-distances-between-circles-tp2492795p2492795.html
> Sent from the ImageJ mailing list archive at Nabble.com.

Karsten
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