get_bar_code_param🔗
Short description🔗
get_bar_code_param — Get one or several parameters that describe the bar code model.
Signature🔗
get_bar_code_param( barcode BarCodeHandle, attribute.name GenParamName, out attribute.name GenParamValue )
Description🔗
The operator get_bar_code_param allows to query parameters
of a bar code model, which are of relevance for a successful search and
decoding of a respective class of bar codes.
The names of the desired parameters are passed in the generic
parameter GenParamName and the corresponding values are
returned in GenParamValue.
All of these parameters can be set and changed at any time with the
operator set_bar_code_param.
Parameters that have been set bar code type specifically by
set_bar_code_param_specific or by automatic parameter training
cannot be read with get_bar_code_param, but must
be read with get_bar_code_param_specific. All parameters listed
with the operator get_bar_code_param_specific can always
be set specifically. Which parameters are actually set specifically can be
determined at runtime with the operator query_bar_code_params.
The following parameters can be queried - ordered by different categories:
Size of the bar code elements:
-
'element_size_min': Minimum size of the base bar code elements, i.e., the minimum width of the narrowest bars and spaces for the specific bar code type.
-
'element_size_max': Maximum size of the base bar code elements, i.e., the maximum width of the narrowest bars and spaces for the specific bar code type.
-
'element_size_variable': Specifies if the element size varies across a single bar code.
-
'barcode_height_min': Minimum height of the bar code.
-
'barcode_width_min': Minimum bar code width.
-
'barcode_width_max': Maximum bar code width.
Scanning settings:
-
'num_scanlines': Maximum number of scans per (candidate) bar code.
-
'min_identical_scanlines': Minimum number of decoded scanlines which return identical data to read the bar code successfully.
-
'majority_voting': Decode result selection mode. Specifies whether majority voting is used in the selection of different scanline results.
-
'stop_after_result_num': Number of successfully decoded bar codes after which the decoding will stop. 0 is the default where the reader tries to decode all candidates.
-
'orientation': Accepted orientation of the decoded bar codes.
-
'orientation_tol': Tolerance of the accepted orientation.
-
'quiet_zone': Quiet zone verification mode.
-
'start_stop_tolerance': Start/Stop search criteria tolerance.
-
'min_code_length': Minimum number of decoded characters.
-
'max_code_length': Maximum number of decoded characters.
-
'merge_scanlines': Determines whether merged scanlines are computed if not enough scanlines could be decoded individually. Thus, occluded or damaged bar codes can be read.
Appearance of the bar code in the image:
-
'meas_thresh': Relative threshold for the detection of edges in the bar code region.
-
'meas_thresh_abs': Absolute threshold for the detection of edges in the bar code region.
-
'contrast_min': Minimum contrast between the foreground and the background of the bar code elements.
Print quality inspection-specific values:
- 'quality_isoiec15416_reflectance_reference': Reference gray value to normalize the reflectances used to assess the quality grades Symbol Contrast, Minimum Reflectance, and Minimum Edge Contrast.
Values that only apply to certain code types:
-
'check_char': Handling of an optional check character.
-
'composite_code': Presence and type of a 2D composite code appended to the bar code.
-
'upce_encodation': Output format for UPC-E bar codes (with number system 0 or 1).
-
'upce1_enable': Enables the decoding of UPC-E bar codes with number system 1.
-
'strict_ean13_upc_a': Defines the distinction of EAN-13 and UPC-A codes.
Miscellaneous:
-
'timeout': Timeout for
find_bar_code -
'persistence': Persistence mode of the bar code model.
-
'train': Returns the names of the trained parameters. The returned tuple can be passed as
GenParamNameto a further call toget_bar_code_paramto get the values of the trained parameters.
Further details on these parameters can be found with the
description of the operator set_bar_code_param.
Execution information🔗
Execution information
-
Multithreading type: reentrant (runs in parallel with non-exclusive operators).
-
Multithreading scope: global (may be called from any thread).
-
Processed without parallelization.
Parameters🔗
BarCodeHandle (input_control) barcode → (handle)
Handle of the bar code model.
GenParamName (input_control) attribute.name(-array) → (string)
Names of the generic parameters that are to be queried for the bar code model.
Default: 'element_size_min'
List of values: 'barcode_height_min', 'barcode_width_max', 'barcode_width_min', 'check_char', 'composite_code', 'contrast_min', 'element_size_max', 'element_size_min', 'element_size_variable', 'majority_voting', 'max_code_length', 'meas_thresh', 'meas_thresh_abs', 'merge_scanlines', 'min_code_length', 'min_identical_scanlines', 'num_scanlines', 'orientation', 'orientation_tol', 'persistence', 'quality_isoiec15416_reflectance_reference', 'quiet_zone', 'small_elements_robustness', 'start_stop_tolerance', 'stop_after_result_num', 'strict_ean13_upc_a', 'timeout', 'train', 'upce1_enable', 'upce_encodation'
GenParamValue (output_control) attribute.name(-array) → (real / integer / string)
Values of the generic parameters.
Result🔗
The operator get_bar_code_param returns the value 2 (H_MSG_TRUE) if the
given parameters are correct. Otherwise, an exception will be raised.
Combinations with other operators🔗
Combinations
Possible predecessors
create_bar_code_model, set_bar_code_param
Possible successors
Alternatives
Module🔗
Bar Code