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Smart Camera / Vision-Sensor / 1D-/2D-Code-Scanner / OCR Reader
Property
Finder
Pattern
Tolerance
Tolerance of the search with respect to a disturbed or missing finder pattern.
The finder pattern includes the L-shaped side as well as the opposite alternat-
ing side. Dependent on this parameter, different algorithms are used during
the symbol search. In one case (’low’), it is assumed that the finder pattern is
present to a high degree and shows almost no disturbances. In the other case
(’high’), the finder pattern may be heavily disturbed or missing completely with-
out influencing the recognition and the reading of the symbol. Note, however,
that in this mode the parameters for the symbol search should be restricted as
narrow as possible. Otherwise the run-time may significantly increase. Also note
that the two algorithms slightly differ from each other in terms of robustness.
This may lead to different results depending on the value of ’Finder Pattern
Tolerance’ even if the finder pattern of the symbol is not disturbed. For example,
if ’high’ is chosen, only symbols with an equidistant module grid can be found
(see below), and hence the robustness to perspective distortions is decreased.
Finally, if ’Finder Pattern Tolerance’ is set to ’any’ both algorithms are applied.
Values: ’low’, ’high’, ’any’ Default: ’low’ (Enhanced: ’low’, Maximum: ’any’)
Module
Grid
Describes whether the size of the modules may vary (in a specific range) or not.
Dependent on this parameter different algorithms are used for calculating the
module’s center positions. If it is set to ’fixed’, an equidistant grid is used. Allowing
a variable module size (’variable’), the grid is aligned only to the alternating side
of the finder pattern. With ’any’ both approaches are tested one after the other.
Please note that the value of ’Module Grid’ is ignored if ’Finder Pattern Tolerance’
is set to ’high’. In this case an equidistant grid is assumed. Values: ’fixed’, ’vari-
able’, ’any’ Default: ’fixed’ (Enhanced: ’any’)
11.12.6. QR Code
Property
Model Type Type of the QR Code model. The old QR Code Model 1 and the newer Model 2
are supported. Values: 1, 2, ’any’ Default: ’any’
Version Min Minimum symbol version. The symbol version is directly linked to the symbol
size. Symbols of version 1 are 21x21 modules in size, version 2 = 25x25 mod-
ules, etc. up to version 40 = 177x177 modules. The maximum size of Model 1
symbols is 73x73 = version 14. Value range: [1 . . . 40] (Model 1: [1 . . . 14])
Default: 1
Version
Max
Maximum symbol version. Value range: [1 . . . 40] (Model 1: [1 . . . 14]) Default:
40
Symbol
Size Min
Minimum size of the symbol in modules. This parameter can be used as an
alternative to ’Version Min’. Value range: [21 . . . 177] (Model 1: [21 . . . 73])
Default: 21
Symbol
Size Max
Maximum size of the symbol in modules. This parameter can be used as an
alternative to ’Version Max’: Value range: [21 . . . 177] (Model 1: [21 . . . 73])
Default: 177
Module
Size Min
Minimum size of the modules in the image in pixels. Values: [1 . . . 100] Default:
6 (Enhanced: 2, Maximum: 1)
Module
Size Max
Maximum size of the modules in the image in pixels. Values: [2 . . . 100] Default:
20 (Enhanced: 100)
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