Operator Reference
get_bar_code_object (Operator)
get_bar_code_object — Access iconic objects that were created during the search or decoding of
bar code symbols.
Signature
get_bar_code_object( : BarCodeObjects : BarCodeHandle, CandidateHandle, ObjectName : )
Description
With the operator get_bar_code_object, iconic objects created
during the last call of the operator find_bar_code can be accessed.
Besides the name of the object (ObjectName), the bar code model
(BarCodeHandle) must be passed to get_bar_code_object.
In addition, in CandidateHandle an index to a single decoded
symbol or a single symbol candidate must be passed. Alternatively,
CandidateHandle can be set to 'all' and then all
objects of the decoded symbols or symbol candidates are returned.
Depending on the option selected in ObjectName parameter
the following objects are returned:
- 'symbol_regions':
-
The regions of successfully decoded symbols are returned. When choosing 'all' as
CandidateHandle, the regions of all decoded symbols are retrieved. The order of the returned objects is the same as infind_bar_code. - 'candidate_regions':
-
The regions of potential bar codes are returned. If there is a total of n decoded symbols out of a total of m candidates then
CandidateHandlecan be chosen between 0 and (m-1). WithCandidateHandlebetween 0 and (n-1) the original segmented region of the respective decoded symbol is retrieved. WithCandidateHandlebetween n and (m-1) the region of the potential or undecodable symbol is returned. In addition,CandidateHandlecan be set to 'all' to retrieve all candidate regions at the same time. - 'scanlines_all', 'scanlines_valid', 'scanlines_all_plain', 'scanlines_valid_plain', 'scanlines_merged_edges':
-
XLD contours representing the particular detected bars in the scanlines applied on the candidate regions are returned. Note that the scanlines can be only be returned if the bar code was decoded by
find_bar_codeordecode_bar_code_rectangle2in 'persistence' mode (seeset_bar_code_paramfor further details).'scanlines_all' represents all scanlines that
find_bar_codecould potentially create in order to decode a bar code.'scanlines_valid' represents only those scanlines that could be successfully decoded. The number of scanlines that has to be valid can be adjusted with
set_bar_code_paramwith the parameter 'min_identical_scanlines'. There will be no 'scanlines_valid' if the symbol was not decoded. For stacked bar codes (e.g., 'GS1 DataBar Stacked' and 'GS1 DataBar Expanded Stacked') this rule applies similarly, but on a per-symbol-row basis rather then per-symbol.'scanlines_merged_edges' shows the scanlines and edges which were used for the merged scanlines (see 'merge_scanlines' in
set_bar_code_param).get_bar_code_objectreturns each scanline as separate XLD contour. Please note that the XLD contours returned by 'scanlines_all', 'scanlines_valid' and 'scanlines_merged_edges' are meant for visualization purposes and hence consist of many XLD points. Double lines are used between edges that the bar code reader recognized as bar, whereas single lines are used for white spaces. Additional information about each scanline can be obtained withget_bar_code_resultwith the parameter 'status'.The '_plain' variants 'scanlines_all_plain' and 'scanlines_valid_plain' return the described scanlines in a plain format. Every edge found is returned as a point of an XLD contour. For every scanline a new XLD contour is created. Scanlines for which no edges could be found are omitted.
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
BarCodeObjects (output_object) object(-array) → object
Objects that are created as intermediate results during the detection or evaluation of bar codes.
BarCodeHandle (input_control) barcode → (handle)
Handle of the bar code model.
CandidateHandle (input_control) integer → (string / integer)
Indicating the bar code results respectively candidates for which the data is required.
Default: 'all'
Suggested values: 0, 1, 2, 'all'
ObjectName (input_control) string → (string)
Name of the iconic object to return.
Default: 'candidate_regions'
List of values: 'candidate_regions', 'scanlines_all', 'scanlines_all_plain', 'scanlines_merged_edges', 'scanlines_valid', 'scanlines_valid_plain', 'symbol_regions'
Result
The operator get_bar_code_object returns the value 2 (
H_MSG_TRUE)
if the given parameters are correct and the requested objects are
available for the last symbol search.
Otherwise, an exception will be raised.
Possible Predecessors
See also
Module
Bar Code