Posted by
Michael Schmid on
URL: http://imagej.273.s1.nabble.com/draw-contour-for-given-pixel-value-tp5003651p5003676.html
Hi Neil,
the standard ImageJ Wand works as a Wand only if you click outside the current selection (press shift-A to deselect if required). When clicking inside the current selection, you can drag the selection to some other position.
If you don't like this behavior, you can use the Versatile_Wand plugin (you have to specify 'include holes' in its options):
http://imagejdocu.tudor.lu/doku.php?id=plugin:segmentation:versatile_wand:start--
For getting the coordinates:
Apart from Tiago's suggestion, Edit>Selection>Properties, you can use the macro command getSelectionCoordinates:
http://rsb.info.nih.gov/ij/developer/macro/functions.html#getSelectionCoordinatesLook at the getCursorLocDemo macro to see how to write a macro that takes mouse coordinates upon a click; then you deselect all, run doWand(x, y, tolerance, mode) and finally get the selection coordinates and save them, process them, or whatever you like, in your macro - which would be nice if you have to do this on many images.
http://rsb.info.nih.gov/ij/macros//GetCursorLocDemo.txtIn a macro, if you have a grayscale image, you could also read the pixel value at that coordinate, threshold the image between this value and maximum, and create a selection. This would eliminate the need for the Wand, which does not work well if you have steep slopes or the image data are noisy.
Michael
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On Jun 26, 2013, at 23:31, Neil Fazel wrote:
> Thanks Michael; the Wand Tool also works. (I find that it's a little finicky; sometimes the contour may be enlarged by clicking outside it, but not made smaller but clicking inside it.)
>
> Do you know of a way to list the XYZ values for a selection created by the Wand Tool?
>
> Neil
>
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