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Version: 6.28.1

Symbology Properties

Symbologies often have different properties, such as symbol count (length of the barcode) or inverted colors (printed white on black). To provide optimal performances, some properties/values are disabled by default in our SDK. You might need to scan a symbology whose properties are by default disabled. This article lists all symbology specific properties, their defaults and possible values.

1D Symbology Properties

  • Color-inverted (bright bars on dark background) decoding for symbologies that support it is disabled and must be explicitly enabled.
  • Optional checksum digits (e.g. for interleaved 2 of 5 codes, or MSI-Plessey codes) are always returned as part of the data.
Symbology        Checksum         Symbol CountSupports Color-InversionExtensions
EAN-13
UPC-A
Mandatory: mod10Default: 12
Range: 12
yesrelaxed_sharp_quiet_zone_check
remove_leading_upca_zero
two_digit_add_on
five_digit_add_on
strict
EAN-8Mandatory: mod10Default: 8
Range: 8
yesrelaxed_sharp_quiet_zone_check
two_digit_add_on
five_digit_add_on
strict
UPC-EMandatory: mod10Default: 6
Range: 6
yesreturn_as_upca
remove_leading_upca_zero
two_digit_add_on
five_digit_add_on
strict
Two-Digit Add-onMandatory: mod10Default: 2
Range: 2
yesstrict
Five-Digit Add-onMandatory: mod10Default: 5
Range: 5
yesstrict
MSI PlesseyMandatory: none
Supported: mod10, mod11, mod1010, mod1110
Default: mod10
Default: 6-32
Range: 3-32
nostrict
Code 128Mandatory: mod103Default: 6-40
Range: 4-50
yesstrip_leading_fnc1
strict
Code 11Mandatory: none
Supported: mod11
Default: mod11
Default: 7-20
Range: 5-34
nostrict
Code 25Mandatory: none
Supported: mod10
Default: 7-20
Range: 3-32
nostrict
IATA 2 of 5Mandatory: none
Supported: mod1010
Default: 7-20
Range: 3-32
nostrict
Matrix 2 of 5Mandatory: none
Supported: mod10
Default: 7-20
Range: 3-32
nostrict
Code 32Mandatory: mod10Default: 8
Range: 8
nostrict
Code 39Mandatory: none
Supported: mod43
Default: 6-40
Range: 3-50
yesfull_ascii
relaxed_sharp_quiet_zone_check
strict
Code 93Mandatory: mod47Default: 6-40
Range: 5-60
yesfull_ascii
strict
CodabarMandatory: none
Supported: mod16, mod11
Default: 7-20
Range: 3-34
nostrict
remove_delimiter_data
GS1 DataBar 14Mandatory: mod10Default: 2
Range: 2
nostrict
GS1 DataBar ExpandedMandatory: mod211Default: 1-11
Range: 1-11
nostrict
GS1 DataBar LimitedMandatory: mod89Default: 1
Range: 1
norelaxed_sharp_quiet_zone_check
strict
ITFMandatory: none
Supported: mod10
Default: 6-40
Range: 4-50
nostrict
RM4SCCMandatory: mod103Default: 7-24
Range: 4-50
no
KIXMandatory: noneDefault: 7-24
Range: 4-50
no
LAPAMandatory: noneDefault: 16
Range: 16
no
USPS Intelligent MailMandatory: noneDefault: 65
Range: 65
no
UPU S18 4-StateMandatory: noneDefault: 19 or 25
Range: 19 or 25
nofluorescent_orange_ink
Australian Post 4-StateMandatory: noneDefault: 10-41
Range: 10-41
noforce_table_c
force_table_n
decode_bar_states
French PostMandatory: nonenofluorescent_orange_ink

2D Symbology Properties

SymbologySupports Color-InversionExtensions
Aztec Codeyes
Data Matrixyesstrip_leading_fnc1 (enabled by default)
direct_part_marking_mode
DotCodeyes
MaxiCodeno
MicroPDF417no
PDF417no
QR Codeyesguess_encoding_disabled
Micro QR Codeyes
ArUcoyes

Symbology Extension Descriptions

ExtensionDescription
full_asciiInterprets the Code39 code data using two symbols per output character to encode all ASCII characters.
relaxed_sharp_quiet_zone_checkEnables scanning codes that have quiet zones (white area before and after the code) that are significantly smaller than allowed by the symbology specification. Use this extension if you are having difficulties to scan codes due to quiet zone violations. However, enabling it may come at the cost of more false positives under certain circumstances.
return_as_upcaTransforms the UPCE result into its UPCA representation.
remove_leading_upca_zeroRemoves the leading zero digit from the result if the UPCA representation extension ‘return_as_upca’ is enabled.
strip_leading_fnc1Removes the leading FNC1 character that indicates a GS1 code. To determine whether a certain code is a GS1 code, use ref sc_barcode_is_gs1_data_carrier.
direct_part_marking_modeUse this mode to improve scan performance when reading direct part marked (DPM) Data Matrix codes. Enabling this extension comes at the cost of increased frame processing times. It is recommended to restrict the scanning area to a smaller part of the image for best performance.
strictEnforce strict standard adherence to eliminate false positives in blurry, irregular or damaged barcodes at the cost of reduced scan performance.
fluorescent_orange_inkEnables the scanning of low contrast fluorescent orange codes. Enabling this option can have a negative impact on the scan performance of other symbologies.
force_table_c, force_table_n and decode_bar_statesFor Australian Post 4-State, customer information is decoded by default with Table N, and Table C is used as a fallback. force_table_c and force_table_n respectively enforce decoding with either C or N tables, and the symbology extension decode_bar_states will return the error-corrected customer information bars as a string of the bar states, A for ascending, D for descending, T for tracker and F for full.
remove_delimiter_dataFor Codabar, removes the start and stop characters from the code and returns only the body of the code in the result.
guess_encoding_disabledBy default QR code encoding is guessed based on the code's data. If guessing is disabled, ISO-8859-1 is reported as default (unless extension use_utf8_as_default_encoding is set to report UTF-8).

Calculating Symbol Counts for Variable-Length Symbologies

The length of data encoded in variable-length symbologies such as Code 128, Codabar, Code 39 etc. is measured as the number of symbols. Depending on the symbology, the symbol count includes the start and end symbol, and/or checksum characters. The following list shows how to calculate the number of symbols for each variable-length symbology. These counts can be used as the input to sc_symbology_settings_set_active_symbol_counts().

Interleaved-Two-of-Five

The number of symbols corresponds to the number of digits in the code. Note that the number of digits must be even. Example: the code c “1234567890123” has a symbol count of 14. For the active symbol count calculation, optional checksum digits are treated like normal data symbols.

Codabar

The number of symbols corresponds to the number of digits in the code, plus the start and end symbols. Example: the code “A2334253D” has a symbol count of 7 + 2 = 9.

Code 11

The number of symbols corresponds to the number of digits in the code, plus one or two checksum symbols. For less than ten digits in the code, one checksum symbol is added. Two checksum symbols are added for ten or more digits in the code. Example: the code c “912-34956” (c “912-349566”) has a symbol count of 9 + 1 = 10. The code c “912-3495-6” (c “912-3495-638”) has a symbol count of 10 + 2 = 12.

Code 128

The number of symbols depends on the encoding used (A, B or C). All encodings require a start, an end and a checksum symbol. The ASCII encoding modes (A and B) store each character in one symbol. Example: the code c “ABC123” in mode A has a symbol count of 6 + 2 + 1 = 9. The numeric encoding mode (C) encodes pairs of digits in one symbol. Example: the code c “123456” has a symbol count of 3 + 2 + 1 = 6. Some encoders switch modes inside the code using switch symbols to optimize the code length. In this case the exact encoding used is needed to compute the number of symbols.

Code 93

The number of symbols corresponds to the number of characters in the code, plus the start and end symbols and 2 checksum digits. Shift characters used in “extended code93” are treated as normal data symbols. Example: the code c “ABCDE12345” has a symbol count of 10 + 2 + 2 = 14.

Code 39

The number of symbols corresponds to the number of characters in the code, plus the start and end symbols. Note that the start and end symbols are not included in the returned barcode data. Example: the code c “4F70050378196356D” (c “4F70050378196356D”) has a symbol count of 17 + 2 = 19.

MSI Plessey and Code 25

The number of symbols corresponds to the number of digits in the code. Example: the code c “12345674” has a symbol count of 8. For the active symbol count calculation, optional checksum digits are treated like normal data symbols.

GS1 DataBar 14

The symbol count corresponds to the number of finder patterns in the code. Each finder is accompanied by two data segments.

GS1 DataBar Expanded

The symbol count cannot be changed at the moment.

RM4SCC

The number of symbols corresponds to the number of characters in the code, including the checksum character.

KIX

The number of symbols corresponds to the number of characters in the code.

Australian Post 4-State

The number of symbol corresponds to 10 digit FCC and DPID codes, and up to 31 characters representing the customer information bar states.