Re: Find maxima .. algorithm discription

Posted by Ayman on
URL: http://imagej.273.s1.nabble.com/Find-maxima-algorithm-discription-tp3683914p3683916.html

<quote author="Michael Schmid-3">
Hi,

sorry, there is no publication on it (at least none that I am aware of,
probably I have reinvented the wheel), but it is rather simple code:
(1) Find the local maxima
(2) Sort them in descending sequence
(3) For each local maximum, do a flood fill algorithm with the gray...

Dear Michael,

I have a followup question about this algorithm. In the ImageJ documentation for "Find Maxima,"  it is stated "Maxima are ignored if they do not stand out from the surroundings by more than [the noise tolerance]." I would have expected that this means that there must be a nonzero number of pixels contiguous with a maximum that exceed the threshold, defined as the maximum minus the noise tolerance.

However, when I used the "Maxima within tolerance" option for the output of "Find Maxima", which the documentation suggests should return all contiguous pixels around the maximum that exceed this threshold, it returned numerous maxima with just one point. This seems inconsistent with my interpretation of how the noise tolerance is used to reject maxima that do not stand out from their surroundings.

Could you clarify how the noise tolerance is used to decide which maxima are ignored?