What it does

Sequence chimera detection based on a different scoring functions.

Chimera detection options

--abskew REAL	min abundance ratio of parent vs chimera (2.0)
--alignwidth INT
	width of alignment in uchimealn output (80)
--chimeras FILENAME
	output chimeric sequences to file
--db FILENAME	reference database for --uchime_ref
--dn REAL	'no' vote pseudo-count (1.4)
--mindiffs INT	minimum number of differences in segment (3)
--mindiv REAL	minimum divergence from closest parent (0.8)
--minh REAL	minimum score (0.28)
--nonchimeras FILENAME
	output non-chimeric sequences to file
--self	exclude identical labels for --uchime_ref
--selfid	exclude identical sequences for --uchime_ref
--uchime_denovo FILENAME
	detect chimeras de novo
--uchime_ref FILENAME
	detect chimeras using a reference database
--uchimealns FILENAME
	output chimera alignments to file
--uchimeout FILENAME
	output to chimera info to tab-separated file
--uchimeout5	make output compatible with uchime version 5
--xn REAL	'no' vote weight (8.0)

For details about this tool, please refer to the GitHub repository or the vsearch manual.