Gray Level Change - Sharp IV-S30 User Manual

Setting Measurement Conditions

(10) Gray level change

To change the gray level, you can change the "**.*TIMES" (magnification by N processing), the "γ+,"
"γ-" (γ (positive/negative) correction), the "CHNG-L" (widening histogram), and the "INCRS-M" (mid
emphasis) functions.
Æ Setting screen
[TYPE MEAS COND]
1OBJECT TYPE NO.
3
[MEAS 1 CAM1 COND]
3CHNG GRAY LVL
4SPACE FILTER
OPS-MENU RETURN LOCK
Gray level change
Magnification by N
processing
(**.* TIMES)
γ
(positive/negative)
correction
Histogram
widening
Mid emphasis
00(0~63) NO YES
NO YES(00.0TIMES γ+ γ- CHNG-L INCRS-M
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.
- γ positive correction: used when the mid gray level is too low.
255
Input image gray level
- γ negative correction: used when the mid gray level is too high.
255
Input image gray level
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
b
0
Gray level
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)
0 127
128 255
3-14
When "OBJECT TYPE
NO." is set to 00.
When "MEASUREMENT
1" is selected.
0 5
Details
255
255
0
m m
Z Z
Gray level
2 Good contrast image
Output image gray level