If values are supplied for com.zero_snrlo and parameter "com.zero_snr" , then the basic mask created by thresholding at the SNR value specified by com.zero_snr is modified by expanding each un-masked " source" area down to an SNR equal to com.zero_snrlo, without introducing any new isolated source areas. The com.zero_snrlo should be lower than the com.zero_snr value. [0]

MAKEMAP, CALCQU