Siemens SIMATIC MV500, Operating Instructions Manual, Page: 65 / 294

Image processing
3.2 Code verification
SIMATIC MV500
Operating Instructions, 03/2021, C79000-G8976-C494-05
65
Quality characteristics
• Symbol contrast:
The symbol contrast is the difference between the average brightness of the points of the
DotCode and the average brightness of the background.
• Grid non-uniformity:
The value indicates the average deviation of the position of the points from an ideal grid
with same distances of grid points in parallel and vertical alignment to the code in each
case.
• Unused error correction:
Proportion of error correction information not used for correction of the read result.
• Print growth:
The print growth specifies the ratio (subtracted from 1) of the average diameter of the
points to the average spacing of the points from each other.
• Cell size:
Average diameter of the points in pixels.
Table 3- 8 Assignment of the numeric grading of DotCode to the quality grades
Quality features
(abbreviation)
Quality grades
4 3 2 1 0
Symbol contrast ≥ 35% ≥ 21% ≥ 14% ≥ 7% < 7%
Grid non-uniformity ≤ 0.1 ≤ 0.3 ≤ 0.4 ≤ 0.5 > 0.5
Unused error correction ≥ 0.62 ≥ 0.50 ≥ 0.37 ≥ 0.25 < 0.25
Print growth ≥ 0.8 and ≤ 1.1 ≥ 0.7 and ≤ 1.2 ≥ 0.6 and ≤ 1.3 ≥ 0.5 and ≤ 1.4 < 0.5 or > 1.4
Cell size ≥ 6 and ≤ 9 ≥ 5 and ≤ 10 ≥ 4 and ≤ 20 ≥ 3 and ≤ 30 < 3 or > 30
3.2.8 Formatted output of the verification
3.2.8.1 Overview
One important feature of a verifier is the ability to document results. To allow this, the optical
reader provides verification reports that can be accessed over the various interfaces. If a
verification report has been configured, this is generated and output each time a read was
successful.
For some verification standards, the standard defines a verification report that can be
regarded as a summary of the verification result.
A detailed verification report consists of the following two parts:
•
Verification settings
• Verification result