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Finds "droplets" (wide peaks) in data ndarray and saves their list in output ndarray. This is a re-implementation of algorithm ImgPeakFinder for ndarray of 2-d segments :with functionality as follows.
1. Select the Selects pixels in the windows defined by the list of parameters:  segment, rowmin,  rowmax, colmin,  colmax
with amplitudes above the threshold_low.
2. Optionally smears image for selected pixels , using 2-d matrix of weights over pixels from in the range -smear_radius to +smear_radius in both dimensions around each smeared pixel amplitude. The matrix of weights is defined by the 2-d Gaussian function of width sigma. If sigma=0 smearing is not applied.
3. Find Finds peaks as pixels with absolute-maximal amplitude above the threshold_high in the center of the matrix covering the range -peak_radius to +peak_radius  in both dimensions.
4. Put Puts the ndarray of found peaks in the event store with key key_droplets. Each row of this ndarray has parameters from struct Droplet, containing segment number,  row, column of the droplet center, peak pixel amplitude, the total amplitude inside peak_radius the region, and the number of pixels in this region above threshold_low:

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• if print_bits is not zero - warning messages will be printed.
• Saves table of droplets/peaks as  ndarray<float,2> with shape=[ndroplets,6]  (see struct Droplet) if key the keyword  peaks_droplets is non-empty.
• A set of threshold parameters should be different in cases when smearing is applied (sigma is not zero) or not.

See also Example for Module ImgAlgos::NDArrDropletFinder

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