thresh - detect samples exceeding a threshold

usage:

thresh [flags] < floatsams > output
 flags:
 -lN	set lower bound to N
 -uN	set upper bound to N
 -RN	set sample rate to N

Input must be file or pipe.  If output is a file or pipe, thresh writes
floatsams exceeding -l and -u values.  If output is terminal, it writes
sample number, time (re. 48KHz unless changed), and sample value.
Arguments may be expressions.