self.add_parameter("keep_discard_read","capture discarded reads to a file.",default=True,type=bool)
self.add_parameter("window_size","set the size of the sliding window as a fraction of the read length, between 0 and 1 (default 0.15).",default=0.15,type=float)
self.add_parameter("limit_score","set the score limit. If the average score within the sliding window drops below this value, the read is discarded (default 10).",default=10,type=int)