Hi Ahmed,
one idea to find paths from left to right:
Add a 1-pixel-wide black line at the left border (may be a 1-pixel wide rectangle).
Then use the Versatile Wand plugin (in 4-connected or 8-connected mode, whatever you prefer, 'include holes' should be off) to select everything connected to the left.
Make sure you have the correct background color of the eyedropper tool (white in your case) and 'Clear Outside'.
Then add a 1-pixel-wide black line at the right border, click with the Wand to the right border, and run 'Clear Outside' again.
In your sample image, almost everything is connected to the left and the right, so there are many paths from the left to the right.
The Versatile Wand is at
http://imagejdocu.tudor.lu/doku.php?id=plugin:segmentation:versatile_wand:startIn contrast to the built-in Wand of ImageJ, the Versatile Wand leaves holes inside a particle unselected (if 'include holes' is off). In the present case, there are several paths that form loops; the ImageJ built-in wand would select everything enclosed by such loops.
Michael
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On Apr 13, 2014, at 20:46, Ahmed Mahmoud wrote:
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