Sharp IV-S30J User Manual page 69

Setting Measurement Conditions
(2) Gray level change
To change the gray level, you can change the
"**.*TIMES" (magnification by N processing), the "
+," " -" (
"CHNG-L" (widening histogram), and the "INCRS-
M" (mid emphasis) functions.
3
Gray level change
Magnification by N
processing
(**.* TIMES)
(positive/negative)
correction
Histogram
widening
Mid emphasis
(positive/negative) correction), the
To improve the contrast (the ratio of high value gray levels to low value gray
levels), specify a magnification rate (00.0 to 99.9) for multiplying the image
data.
- If the magnified gray level exceeds 255, the system will correct the value
to 255.
- positive correction: used when the mid gray level is too low.
255
- negative correction: used when the mid gray level is too high.
255
This is a method to widen the histogram of an image in which the histogram
is at part of it, thus improve its contrast.
a
0
1 Bad contrast image
Emphasize the mid gray level.
- This improves contrast while remaining the background image.
- The input image density (G) can be converted to the output image density
with the following formulas:
Input image gray level(G)
0 to 127
128 to 255
IMG PRE-PROC SCREEN COND SAVE
1COMPARE IMGS
2CHNG GRAY LEVEL
3SPACE FILTER
Details
255
Input image gray level
255
Input image gray level
b
m
Z
0
Gray level Gray level
2 Good contrast image
Output image gray level
3-22
F C1 BRT
NO
NO
NO
CONTRAST MAGNI
+
NO
-
CHNG-L
INCRS-M
m
Z