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• par[0] - algorithm #
• par[1] - maximal threshold on intensity to evaluate mean for low intensities
• par[2] - maximal allowed common mode correction

• par[3] - length of consecutive pixel array for common mode evaluation
  For example, for pnCCD

  Code Block
  1 1000 1000 128

• The algorithm loops over the data and evaluates consecutive arrays of specified length (which might represent for example a row of pixels in a readout chip) and finds the mean value for values below a threshold, ignoring masked pixels.  It corrects all the data if the calculated common mode is less than the maximal allowed correction.

#3 - MEDIAN evaluation

Parameters are the same as in #2.  The algorithm is as above, except that it calculates the median, or the average of the two median points if there are an even number passing the selection criteria.

Test of the common mode correction for pnCCD

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