Pike
Technical
Manual
V5.2.3
122
Description of the data path
Description
of
the
data
path
How to store shading image
There
are
two
storing
possibilities:
•
After
generating
the
shading
image
in
the
camera,
it
can
be
uploaded
to
the
host
computer
for
nonvolatile
storage
purposes.
•
The
shading
image
can
be
stored
in
the
camera
itself.
The
following
pictures
describe
the
process
of
automatic
generation
of
correction
data
(Pike
F-032C).
Surface
plots
and
histograms
were
created
using
the
ImageJ
program.
•
On
the
left
you
see
the
source
image
with
non-uniform
illumination.
•
The
surface
plot
on
the
right
clearly
shows
a
gradient
of
the
brightness
(0:
brightest
255:
darkest
pixels).
•
The
histogram
shows
a
wide
band
of
gray
values.
By
defocusing
the
lens,
high-frequency
image
data
is
removed
from
the
source
image,
therefore
its
not
included
in
the
shading
image.
Figure 44: Shading correction: Source image with non-uniform illumination
surface plot
histogram
255.0
0.0
48
0.0
p
ix
els
640.
0 pix
els
256
0
Count: 307200
Min: 79
Mean: 135.337
Max. 19
StdDev. 30.497
Mode: 88 (4200)