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Test of the NDArrCalib module for pnCCD.

Module ImgAlgos::NDArrDropletFinder

Finds "droplets" (wide peaks) in data ndarray and saves their list in output ndarray. This is a re-implementation of algorithm ImgPeakFinder for ndarray 2-d segments:
1. Select the pixels in the windows 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 -smear_radius to +smear_radius 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 peaks as pixels with absolute-maximal amplitude above the threshold_high in the center of the matrix -peak_radius to +peak_radius.
4. Put the vector or ndarray of found peaks in the event with key peaksKey or peaks_nda respectively. Each entry of this vector has an object of the struct Peak, containing x, y positions, peak pixel amplitude, the total amplitude in the matrix, defined by the peak_radius, and the number of pixels in the matrix above threshold_low:

  struct Droplet{
    unsigned seg;
    double   row;
    double   col; 
    double   ampmax;  // amplitude in the peak maximum
    double   amptot;  // total amplitude in the range of {{peak_radius}}
    unsigned npix;    // number of pixels in the range of {{peak_radius}}
  };

Remarks:

• 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 peaks_droplets is non-empty.

See also Example for Module ImgAlgos::NDArrDropletFinder

Module ImgAlgos::PixCoordsProducer

Functionality

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