Operator Reference
get_bar_code_result (Operator)
get_bar_code_result — Get the alphanumerical results that were accumulated during the
decoding of bar code symbols.
Signature
get_bar_code_result( : : BarCodeHandle, CandidateHandle, ResultName : BarCodeResults)
Description
The operator get_bar_code_result returns
alphanumeric results of the reading process in BarCodeResults.
In order to obtain a result, the bar code model (BarCodeHandle)
and the index of the resulting symbol or candidate
(CandidateHandle) are needed. ResultName determines what
kind of result is to be returned.
CandidateHandle refers to the read candidates in the order as
returned by the operator find_bar_code.
This implies, the possible values for CandidateHandle depend on the
queried result:
-
Referring to decoded symbols, values from 0 to (n-1) are possible (with n as the total number of successfully decoded symbols).
-
Referring to candidates, values from 0 to (m-1) are possible (with m as the total number of candidates).
In case the asked result is single valued,
CandidateHandle can also be set to 'all'
to return the results of all symbols or candidates.
The following values are supported for ResultName:
- 'decoded_strings':
-
returns the decoded result as a string in a human-readable format. Note that only data characters are contained in the decoded string. Start, stop, and check characters are excluded. For optional check characters the behavior depends on the value of the 'check_char' (see
set_bar_code_paramfor details) parameter.The returned result is a single value.
- 'decoded_types':
-
returns the bar code type of the decoded result as a string. This is especially important in the context of autodiscrimination (see
find_bar_code).The returned result is a single value.
- 'decoded_data':
-
returns the decoded result as a tuple of byte values. In contrast to 'decoded_reference', this contains the same high level processed data that is also returned for 'decoded_strings'. However, if the data contains binary non-printable characters, this parameter is more convenient. Also, for Code 128 or Code 93, the decoded data may contain NULL characters. In this case, the data can only be fully retrieved using this parameter, as the NULL character will otherwise terminate the string.
- 'decoded_reference':
-
returns the underlying decoded reference data. It comprises all original characters of the symbol, i.e., data characters, potential start or stop characters and check characters if present. The specific result depends on the code type:
-
For codes taking only numeric data, like, e.g., the EAN/UPC codes, the GS1 DataBar codes (except the GS1 DataBar Expanded variants), or the 2/5 codes, the decoded reference data takes the same values as the decoded string data including check characters.
-
For codes with alphanumeric data, like for example Code 128 or Code 39 the decoded reference data are the indices of the respective decoding table.
-
For GS1-128, the decoded reference data are the indices of the respective decoding table. The special character FNC1 appears with value 102.
-
For GS1 DataBar Expanded and GS1 DataBar Expanded Stacked, the reference values are the ASCII codes of the decoded data (see also Tuple / String Operations), where the special character FNC1 appears with value 29.
-
Furthermore, for all codes from the GS1 DataBar family the first reference value represents a linkage flag with value of 1 if the flag is set and 0 otherwise.
The result is returned as a tuple.
-
- 'composite_strings':
-
returns the decoded string of a GS1 Composite component. For further details see the description of the parameter 'composite_code' of
set_bar_code_param.The returned result is a single value.
- 'composite_reference':
-
returns the decoded string of a GS1 Composite component as a tuple of byte values. If the data contains binary non-printable characters, this parameter is more convenient than 'composite_strings'.
- 'orientation':
-
returns the orientation for the specified result. The 'orientation' of a bar code is defined as the angle between its reading direction and the horizontal image axis. The angle is positive in counter clockwise direction and is given in degrees. Note that the reading direction is perpendicular to the bars of the bar code. In cases where the orientation of the bars can not be determined reliably, e.g., for distorted codes, the orientation of the scanlines is returned.
The returned result is a single value.
Value range: -180.0 .. 180.0.
- 'element_size':
-
returns the size of bar code elements for the specified result.
The returned result is a single value.
- 'aborted':
-
returns a value indicating whether
find_bar_codewas aborted or not:- 0 - completed
find_bar_codecompleted.- 1 - aborted
find_bar_codewas aborted by a timeout, seeset_bar_code_param.- 2 - aborted
find_bar_codewas aborted usingset_bar_code_paramwith 'abort'.
The returned result is a single value.
- 'quality_isoiec15416':
-
returns a tuple with the assessment of print quality in compliance with the international standard ISO/IEC 15416:2016. Note that the print quality of a bar code can only be evaluated if the bar code was decoded by
find_bar_codein 'persistence' mode (seeset_bar_code_paramfor further details).The first tuple element always contains the overall print quality of the symbol. The length of the tuple and the interpretation of the remaining elements depend on whether a simple 1D bar code is evaluated (e.g., EAN-13, Code 128, GS1 DataBar) or a composite bar code (e.g., GS1 DataBar Omnidirectional CC-A, GS1 DataBar Limited CC-B). The names of the grades can be queried by setting
ResultNameto 'quality_isoiec15416_labels', see below.For the print quality assessment a set of scan reflectance profiles (scan lines) is generated across the symbol. For each scan line a grade for each of the evaluated parameters is allocated.
For compatibility reasons these grades are numbers from 0 to 4, where 0 is the worst and 4 the best possible grade. Setting
ResultNameto 'quality_isoiec15416_float_grades', the grades are returned in accordance with the standard with one decimal place. The worst of all parameter grades of a scan line is defined as the scan reflectance profile grade. Thus, each scan line has an own grade representing the respective minimal grade of all parameter grades of this scan line. The arithmetic mean of all those scan line grades is then returned as the overall symbol grade.If a grade is not defined for the bar code type of the decoded symbol, 'N/A' is returned. In this case, the overall symbol grade is also 'N/A'.
It is important to note that, even though the implementation is strictly based on the standard, the computation of the print quality grades depends on the decoding algorithm used. Thus, different bar code readers (of different vendors) can potentially produce slightly different results in the print quality assessment.
The tuple describing the print quality depends on whether the bar code is simple or composite:
- simple 1D bar codes:
-
The valuation of the print quality is described in a tuple with the following nine elements:
- 0 - overall quality:
The arithmetic mean of the scan reflectance profile grade of each scan line. Note, that this value is, in most cases, not the minimum of the other symbol grades, because it depends on the individual scan reflectance profile grades.
- 1 - decode:
Set to 4 when the reflectance profile of the symbol could be decoded according to the reference decode algorithm for the symbology and 0, otherwise. Note that HALCON's decode algorithm differs from the reference decode algorithm. Thus, in many cases HALCON can decode the symbol although the decode grade according to the standard is 0.
- 2 - symbol contrast:
The range between the minimal and the maximal value in the reflectance profile. A strong contrast results in a good grading.
- 3 - minimal reflectance:
Set to 4 if the lowest reflectance value in the scan reflectance profile is lower or equal to 0.5 of the maximal reflectance value. Otherwise a value of 0 is assigned.
- 4 - minimal edge contrast:
The contrast between any two adjacent elements, both bar-to-space or space-to-bar. The minimal edge contrast grades the minimum of the edge contrast values measured in the reflectance profile.
- 5 - modulation:
Indicates how strong the amplitudes of the bar code elements are. Big amplitudes make the assignment of the elements to bars or spaces more certain, resulting in a high modulation grade.
- 6 - defects:
Reflects irregularities in the gray value profile found within elements and quiet zones.
- 7 - decodability:
Reflects deviations of the element widths from the nominal widths defined for the corresponding symbology.
- 8 - additional requirements:
-
A grade concerning symbology specific requirements of the bar code. It mostly regards the required quiet zones, but sometimes it can also be related to e.g., wide/narrow ratio, inter-character gaps, guarding patterns. For the following code types the conformity to the corresponding ISO/IEC standard cannot be guaranteed. This is mainly because the computation of the additional requirements requires the availability of metrical information.
- Code 39:
the grade of the inter-character gap depends on the measured narrow element width given in millimeters. Since in
find_bar_codeneither metric information is available nor can be calculated,get_bar_code_resultwill only return the grade for the inter-character gap assuming that the measured narrow element width is less than 0.287mm.- EAN-13, EAN-8, UPC-A, UPC-E (including all add-on variants):
ISO/IEC 15420:2009 specifies the magnification factors as an additional criterion. A computation of this criterion is not possible since this would require knowledge of the metrical size of the bar code.
While overall quality is the final symbol grade to be reported, the rest of the grades give information for possible causes for poor quality of a symbol. A detailed list of frequently appearing defects and their effect on the individual grades can be found with the ISO/IEC 15416:2016 standard.
- composite bar codes:
-
The valuation of the print quality is described in a tuple with 24 elements, which we organize for better clarity in three groups:
OVERALL,LINEAR, andCOMPOSITE, the latter one including a sub group. The overall grades that are listed in the groupOVERALL. The grades in the groupsLINEARandCOMPOSITEgive information of possible causes for poor quality of the symbol.In the following, the individual tuple elements with their corresponding index and definition are listed in groups.
-
The group
OVERALL:These grades represent the respective minimum of all individual grades of each group.
- 0 - overall quality:
The final symbol grade to be reported. It returns the minimum of all grades.
- 1 - overall linear:
The overall grade for the symbols of the group
LINEAR, the linear 1D symbols. This grade returns the minimum of all grades belonging to the group.- 2 - overall composite:
The overall grade for the symbols of the group
COMPOSITE, the composite 2D symbols. This grade returns the minimum of all grades belonging to the group.
-
The group
LINEAR:The interpretation of the grades in the
LINEARgroup correspond to those for simple 1D bar codes described above.- 3 - decode
- 4 - symbol contrast
- 5 - minimal reflectance
- 6 - minimal edge contrast
- 7 - modulation
- 8 - defects
- 9 - decodability
- 10 - additional requirements
-
The group
COMPOSITE:these grades are equivalent to the quality grades for PDF 417 data code symbols, thus of two-dimensional symbols according to ICO/IEC 15415:2011 (see 'quality_isoiec15415' in
get_data_code_2d_results). However, there is a difference: For PDF 417 data code symbols a start/stop pattern is used for the evaluation concerning the quality of the reflectance profile. In contrast, for composite bar codes so-called Raw Address Patterns (RAP) are used instead of a start/stop pattern. The grades of the respective RAP symbols are organized in the sub groupCOMPOSITE RAPand are consistent with the grades for simple 1D bar codes.- 11 - decode:
Grade for the decodability of the composite symbol part. Its meaning and determination is equivalent to the one for simple 1D bar codes described above.
- 12 - RAP overall:
Minimum of all individual grades of the sub group
COMPOSITE RAP.- 13 - RAP contrast:
Grade of the
COMPOSITE RAPsub group, corresponds to the one for simple 1D bar codes as described above.- 14 - RAP minimal reflectance:
Grade of the
COMPOSITE RAPsub group, corresponds to the one for simple 1D bar codes as described above.- 15 - RAP minimal edge contrast:
Grade of the
COMPOSITE RAPsub group, corresponds to the one for simple 1D bar codes as described above.- 16 - RAP modulation:
Grade of the
COMPOSITE RAPsub group, corresponds to the one for simple 1D bar codes as described above.- 17 - RAP defects:
Grade of the
COMPOSITE RAPsub group, corresponds to the one for simple 1D bar codes as described above.- 18 - RAP decodability:
Grade of the
COMPOSITE RAPsub group, corresponds to the one for simple 1D bar codes as described above.- 19 - codeword yield:
Counts and evaluates the relative number of correct decoded words acquired by the set of scan profiles.
- 20 - unused error correction:
Counts and evaluates the relative number of false decoded words within the error correction blocks.
- 21 - modulation:
Grades the ratio of the minimum edge contrast to the symbol contrast. indicates how strong the amplitudes, i.e., the extremal intensities, of the bars and spaces are.
- 22 - decodability:
Grades the uniformity of reflectance of the dark and light modules, respectively.
- 23 - defects:
Refers to a measurement of how perfect the reflectance profiles of bars and spaces are.
-
- 'quality_isoiec15416_float_grades':
-
returns a tuple with the same assessment of print quality like 'quality_isoiec15416'. In compliance with the international standard ISO/IEC 15416:2016 the grades are returned with one decimal place. The names of the grades can be queried by setting
ResultNameto 'quality_isoiec15416_labels', see below.Note that the print quality of a bar code can only be evaluated if the bar code was decoded by
find_bar_codein 'persistence' mode (seeset_bar_code_paramfor further details). - 'quality_isoiec15416_values':
-
returns a tuple with the raw values for all 'directly measurable' grades (returned with
ResultNameto 'quality_isoiec15416'). These are the grades, whose definition in the ISO/IEC 15416:2016 standard is a 'direct derivative' of the reflectance (i.e., the gray values) properties of the symbol or grades that are the result of a 'direct counting'. Additionally the three overall grades overall quality, overall linear, and overall composite are returned (see their explanation above in 'quality_isoiec15416'). Note that the print quality of a bar code can only be evaluated if the bar code was decoded byfind_bar_codein 'persistence' mode (seeset_bar_code_paramfor further details).The names of the tuple elements can be queried by setting
ResultNameto 'quality_isoiec15416_labels', see below.All values (not grades) are normalized between 0.0 and 1.0. Hence, for example, a symbol contrast value of 0.75 will correspond to a gray value of 191.25 (for byte images).
Which values make up the tuple depends on whether the bar code is a simple 1D or a composite bar code:
- simple 1D bar codes:
-
The following values are returned by the respective index:
- 0 - overall quality
- 2 - symbol contrast
- 3 - minimal reflectance
- 4 - minimal edge contrast
- 5 - modulation
- 6 - defects
- 7 - decodability
- composite bar codes:
-
The following values are returned by the respective index:
- 0 - overall quality
- 1 - overall linear
- 2 - overall composite
- 4 - symbol contrast
- 5 - minimal reflectance
- 6 - minimal edge contrast
- 7 - modulation
- 8 - defects
- 9 - decodability
- 13 - RAP contrast
- 14 - RAP minimal reflectance
- 15 - RAP minimal edge contrast
- 16 - RAP modulation
- 17 - RAP defects
- 18 - RAP decodability
- 19 - codeword yield
- 20 - unused error correction
These tuples have the same length as the tuple with the grades returned when setting
ResultNameto 'quality_isoiec15416' and 'quality_isoiec15416_float_grades', respectively. For the entries not listed above, the operator reports 'N/A'. In case of simple 1D bar codes, the grades decode and additional requirements do not have any interpretation in the reflectance profile and as a consequence the value 'N/A' is returned. For composite bar codes this is the case for the grades decode (LINEAR), additional requirements (LINEAR), decode (COMPOSITE), and RAP overall (COMPOSITE). Note that although the grades modulation (COMPOSITE), decodability (COMPOSITE), and defects (COMPOSITE) are grading the gray value reflectance profile of a composite symbol, 'N/A' is reported for them as well. This is because they are computed in a complicated scheme involving the symbology decoding routine and the error correction mechanism. As a consequence they do not have a direct raw measurement interpretation.If a grade is not defined for the bar code type of the decoded symbol, 'N/A' is returned as its value. In this case, the value of the overall symbol grade is also 'N/A'.
- 'quality_isoiec15416_labels':
-
returns convenience grade labels of the elements of the tuple returned when calling
get_bar_code_resultwith 'quality_isoiec15416'. Note, that in order to be able to discriminate the composite from the linear grading case, the operator needs a handle of a valid result to be passed inCandidateHandle. - 'gs1_lint_passed':
-
If the symbol contains a GS1 formatted string, additional linting can be performed on the contained string. 'gs1_lint_passed' will return 'true', if this is successful. Otherwise, 'false' is returned. Linting checks that
-
one AI (Application Identifier) does not occur multiple times with different contents,
-
AIs required by other AIs are contained,
-
AIs excluded by other AIs are not included, and that
-
specific formatting rules for AIs are respected.
-
- 'gs1_lint_result':
-
'gs1_lint_result' performs the linting tests documented in 'gs1_lint_passed'. If the linting fails, a list of human-readable error messages is returned, if it is successful, 'ok' is returned.
- 'status':
-
determines and returns additional information about scanlines of a given candidate region in a human-readable format. Note in order to evaluate the status of the bar code scanlines the preceding call of the operator
find_bar_codeordecode_bar_code_rectangle2needs to be done in the mode 'persistence', seeset_bar_code_param.For the calculation of additional information the given candidate region is scanned again. In doing so, the bar code reader exits only after evaluation of all scanlines and not usual after a successful decoding. This is computationally expensive and should be queried only if additional information is needed. For further information on setting scanline parameters, see
set_bar_code_param.The operator returns for every scanline of the candidate region a status message and possible warning message, which will be added to the string containing the status message. These messages are sorted in the same order as the scanlines themselves are returned by
get_bar_code_objectwith the parameter 'scanlines_all'. The possible messages of these categories are listed below.-
Status messages:
The following list shows the possible messages grouped into stages in which the message can appear. The numbers are the corresponding status codes returned by 'status_id' (see below).
- 0 - 'unknown status.'
The status of this scanline is unknown. The scanline will be ignored.
- 1 - 'success.'
The scanline could be decoded successfully.
- 2 - 'edges: not enough edges detected.'
The number of edges in this scanline is too low for this bar code type.
- 3 - 'edges: not enough edges for a start, a stop and at least one data character.'
The number of edges in this scanline is too low to find at least the start pattern, the stop pattern and a data character.
- 4 - 'edges: too many edges detected.'
The number of edges in this scanline is too high for this bar code type.
- 5 - 'edges: center of scanline not within image domain.'
- 6 - 'decoding: could not find stop character.'
The symbology specific stop character could not be found.
- 7 - 'decoding: could not find start and stop characters.'
The symbology specific start and stop characters could not be found.
- 8 - 'decoding: internal error when estimating the maximum string length.'
Internal error.
- 9 - 'decoding: internal error when decoding a single character.'
Internal error.
- 10 - 'decoding: number of wide bars of a single character is not equal to 2.'
For bar code types '2/5 Industrial' and '2/5 Interleaved', the number of wide bars in a single character must be two.
- 11 - 'decoding: invalid encoding pattern.'
The encoding pattern does not correspond to a character in the symbology specific decoding table.
- 12 - 'decoding: invalid mix of character sets.'
For bar code types 'EAN-13' and 'UPC-A', the left half of the symbol contains an invalid mix of the number sets A and B.
- 13 - 'decoding: error decoding the reference to a human readable string.'
For example, this could happen if not enough characters (depending on whether a check character is expected) could be found.
- 14 - 'decoding: could not detect center guard pattern.'
For bar code types 'EAN-13', 'EAN-8', and 'UPC-A' (including add-on variants) the obligatory center guard pattern could not be found.
- 15 - 'decoding: could not detect left and/or right guard patterns.'
For bar code types 'EAN-13', 'EAN-8', and 'UPC-A' (including add-on variants) either the obligatory left or right normal guard patterns could not be found. For bar code types 'UPC-E' (including add-on variants) either the left normal or right special guard patterns could not be found.
- 16 - 'decoding: could not detect add-on guard pattern.'
For bar code types 'EAN-13', 'EAN-8', 'UPC-A', and 'UPC-E' containing add-on symbols, the obligatory add-on guard pattern could not be found.
- 17 - 'decoding: could not detect enough finder patterns.'
For bar code types of the GS1 DataBar family, not enough finder patterns could be found.
- 18 - 'decoding: no segment found.'
For stacked bar code types no segment could be found.
- 19 - 'check: checksum test failed.'
The check character test failed. For bar codes with an optional check character, it is possible to disable the check character testing with 'check_char' in
set_bar_code_param.- 20 - 'check: check of add-on symbol failed.'
For bar code types 'EAN-13', 'EAN-8', 'UPC-A', and 'UPC-E' containing add-on symbols, the mix of the number sets A and B does not match the implicit check digit.
- 21 - 'check: detected EAN-13 bar code type instead of specified type.'
For the bar code type 'UPC-A' and its add-on variants, the left half of the symbol must consist of six symbol characters of number set A, but a 'EAN-13' compatible mix of number sets A and B has been found instead. Try decoding the bar code as 'EAN-13'.
- 22 - 'check: symbol region overlaps with another symbol region'
The bar code could be decoded, but its symbol region intersects with the symbol region of another successfully decoded symbol.
- 23 - 'decoding: could not detect the bar code type.'
While scanning a candidate region in autodiscrimination mode (see
find_bar_codewithCodeType='auto'), the decoder was unable to detect which bar code type the symbol belongs to.- 24 - 'decoding: quiet zone is disturbed.'
The quiet zone check was not successful. See the section 'quiet_zone' in
set_bar_code_paramfor further information.- 25 - 'check: symbol region detected outside of the candidate region.'
A bar code could be decoded, but the resulting symbol region does not intersect the original candidate region. This is an indication that random clutter or another candidate was detected by accident by the scanlines used to scan the original candidate.
- 26 - 'decoding: minimum code length not reached (see min_code_length).'
The number of characters in the found code is smaller than the required amount. See the section 'min_code_length' in
set_bar_code_paramfor further information about the minimal required code length.- 27 - 'decoding: maximum code length exceeded (see max_code_length).'
The number of characters in the found code exceeds the maximum. See the section 'max_code_length' in
set_bar_code_paramfor further information about the maximum allowed code length.- 28 - 'decoding: could not estimate bar width threshold.'
Specific to Pharmacode. It was not possible to estimate a threshold to distinguish between wide and narrow bars.
-
Warning messages:
The messages listed below are only warnings, not errors. They can appear in combination with a status message and are then added to the status message string. These messages are returned if the bar code reader detects possible quality issues in the input image. The messages 1000 to 1003 can appear only for successfully decoded scanlines and only for the following bar code types: 'Codabar', '2/5 Industrial', '2/5 Interleaved', 'Code 39', 'Code 93', 'GS1-128', 'Code 128', 'MSI', all 'EAN'-, 'UPC-A'- and 'UPC-E'-variants. Note that in cases where scanlines were already decoded incorrectly but not recognized as invalid by the bar code reader, these warnings will be wrong and must be ignored.
- 1000 - 'White spaces too wide.'
The measured width of the white spaces is bigger than internally expected. This is not a decoding error, but a warning that increasing white spaces could lead to undecodable symbols.
- 1001 - 'White spaces too narrow.'
The measured width of the white spaces is smaller than internally expected. This is not a decoding error, but a warning that decreasing white spaces could lead to undecodable symbols.
- 1002 - 'Bars too wide.'
The measured width of the bars is bigger than internally expected. This is not a decoding error, but a warning that increasing the width of the bars could lead to undecodable symbols.
- 1003 - 'Bars too narrow.'
The measured width of the bars is smaller than internally expected. This is not a decoding error, but a warning that decreasing the width of the bars could lead to undecodable symbols.
- 1004 - 'Possible saturation of gray values.'
Internal algorithms show that the white pixels in the symbol region could be saturated. This warning is not bar code type specific. This warning is returned for each scanline. For example, the combination of the status messages 1001/1004 or 1003/1004 is a hint, that the input images might be overexposed.
- 1005 - 'No composite component found.'
The linkage flag in the linear bar code component indicates that there should be a composite component, but the composite component could not be found. The decoder returned the linear component only. This warning is returned for each scanline.
- 1006 - 'Used for merging.'
This message is an information that some edges of the current scanline were used to compute the merged scanline.
-
- 'status_id':
-
returns additional information about scanlines in a numeric format that can be easily parsed. The description of this functionality and the message numbers are described with the parameter 'status' above. The numbers of the warnings can be returned together with other status numbers. The single status message and warning numbers for each scanline are returned as a string, separated by a semicolon, e.g.,
'1;1000;1004'. - 'status_small_elements_robustness':
-
determines the status of an optional decoding attempt, which is described in the section about 'small_elements_robustness' in
set_bar_code_param. Additionally to the messages listed for 'status', 'status_small_elements_robustness' can return the status 'small_elements_robustness: no scan.' if for some reason the algorithm was not executed or failed. - 'decode_feature':
-
returns the feature that is used for the successful symbol decoding.
The returned result is a single value.
Suggested values: 'standard', 'merge_scanlines', 'small_elements_robustness'.
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.
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'
ResultName (input_control) attribute.name → (string)
Names of the resulting data to return.
Default: 'decoded_types'
Suggested values: 'decoded_types', 'decoded_strings', 'decoded_data', 'decoded_reference', 'element_size', 'orientation', 'composite_strings', 'composite_reference', 'aborted', 'gs1_lint_result', 'gs1_lint_passed', 'quality_isoiec15416', 'quality_isoiec15416_labels', 'quality_isoiec15416_values', 'quality_isoiec15416_float_grades', 'status', 'status_id', 'status_small_elements_robustness', 'decode_feature'
BarCodeResults (output_control) attribute.value(-array) → (string / integer / real)
List with the results.
Result
The operator get_bar_code_result returns the value 2 (
H_MSG_TRUE)
if the given parameters are correct and the requested results are
available for the last symbol search.
Otherwise, an exception will be raised.
Possible Predecessors
See also
Module
Bar Code