Service manual

CHAPTER 2
2 - 16
COPYRIGHT © 2000 CANON INC. CANOSCAN FB1210U REV.0 APR. 2000 PRINTED IN JAPAN (IMPRIME AU JAPON)
ABCD
EFGH
ABCD
EFGH
A
BCD
EFGH
A'
E'
CCD
reading
data
Output
image
data
Thinned data
CCD
reading
data
Output
image
data
Averaged data=(A+B+C+D)/4
F. Averaging
When reading images at lower resolution, the thinned data increases resulting in output
image deterioration. Averaging is a process in which the data to be thinned and the data to be
actually output are averaged and output, in order to suppress the image deterioration due to
the data thinning.
Figure 2-13