Casio IT-800 Series, Software Manual, Page: 53 / 325

53
Noise Filter
If the background of printed bar code is white color, a noise tends to be generated easily during
scanning causing the error rate to increase. To reduce such the noise, the Noise Filter function is
available with the terminal. Two methods, software noise filter and ASIC noise filter, are
available. However, the ASIC noise filter has been set always effect by the system. Thus, it is not
possible for the user to reset it in the Read operation tab of Setting Scanner.
Table 2.48
Filter Description Merit Demerit
Software
noise filter A software process removes noise. In
determining the blank at the leading edge
of the bar code, if there is a bar width
smaller than a certain value, it will be
bonded to the fore and aft data, the noise
eliminated and the determination made.
Also, the time in the range of 1 to 8
seconds from scanning to the time the
software filter initiates can be set. The
default is 3 seconds. Effective when
scanning leading
edge blank of
bar code using
laser module
noted for easily
picking up noise. If initial bar is
extremely thin, it
will be
determined as
noise and
eliminated,
which may mean
that the bar code
cannot be
scanned.
The functions of the Laser Scanner Library relevant to the Noise Filter are as follows.
OBRSetFilter
:
Sets up noise filter mode.
OBRGetFilter
:
Retrieves noise filter mode.
OBRSetFilterOnTimer
:
Sets up start time for noise filter.
OBRGetFilterOnTimer
:
Retrieves start time for noise filter.