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Algorithm of peak_finder_v3

• makes a map of pixels with local maximums of requested rank for data ndarray using mask,and mask, pixel code in the map may have bits 0/1/2/4 standing for not-a-maximum / maximum-in-row / maximum-in-column / maximum-in-rectangular-region of radius=rank.
• for each pixel with local maximal for each peak candidate defines the number of pixels, total intensity in the region defined by the rank radius evaluates background level, rms of noise, and S/N using parameterscounts a number of pixels with intensity above zero, total positive intensity, center of gravity coordinates and rms,
• using parameters r0(ex. r0=5.0), dr(ex.=0.05) evaluates background level, rms of noise, and S/N for the pixel with maximal intensity.
• makes list of peaks which pass selector with parameters set in set_peak_selection_parsapply peak selection parameters, for example

alg.set_peak_selection_pars(npix_min=5, npix_max=500, amax_thr=0, atot_thr=1000, son_min=6)

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Test for 100x100 image with random normal distribution of intensities

Maps Example of the map of local maximums found for rank from 1 to 5:

pixel color coding of pixels:

• blue=0 - not a local maximum
• green=1 - local maximum in row
• yellow=1+2 - local maximum in row and column
• red=1+2+4 - local maximum in rectangular region of radius=rank.

Table for rank, associated 2-d region size, and fraction of pixels recognized as local maximums for rank, and time consumption for this algorithm.

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