Barcode Basics

1
HHR-TSPHand Held ReadersTechnical
SupportBarcodes and 2D codesPlace -
DD/MM/YYYY - Session XXBar CodeBasics
2
Agenda

• When Day DD/MM/YYYY
• Where Place
• Who Speaker / Professional qualification
• What Bar Code Basics
• Duration HHMM hours
• Level Basic

3
Modules Contents

• Main Bar Code Characteristics
• Code 2 of 5 Interleaved
• Code 39
• Code 128
• Code EAN-128 and Application Identifiers (AI)
• A Comparison Between 2/5, 39, 128
• Codes EAN - UPC - JAN
• Other codes
• Summary

4
Bar Code Basics
5
Bar Code Principles

• Element bar or space
• Barcount number of bars and spaces
• Start/Stop fixed patterns used to detect bar
  code

6
Bar Code Principles

• Resolution X module size width of the
  narrowest element in mm (mils in USA)
• Aspect Ratio bars height to symbols length
• Quiet Zone white margins (Overflow quiet zone
  time duration)Usually the Quiet Zone width must
  be 10 times X

7
Bar Code Principles
Stop pattern
Start pattern
Quiet Zone
Quiet Zone
123456
Scan Line
8
Bar Code Types Levels

• 2 Levels Bar Codes (IL 2/5, 39, Codabar )
• elements can assume only two different
  widths NARROW and WIDE
• N Printing Ratio ratio between the wide and
  the narrow element
• the range of N is from 2 1 to 3 1

9
Bar Code Types Levels

• 4 Levels Bar Codes (128, EAN-128, EAN-8,
  EAN-13, UPC-A, UPC-E, JAN )
• elements can assume only four different
  widths 1X - 2X - 3X - 4X
• Printing Ratio N does not apply

10
Bar Code Types Continuous/Discrete

• Continuous all spaces within the symbol are
  parts of characters. Examples IL2/5, 128,
  EAN128, EAN-8, EAN-13, UPC-A, UPC-E
• Discrete the spaces between the characters
  (Intercharacter Gap) are not part of the
  characters. Examples code 39, Codabar

Edge of next character
Character 3
Character 1
Character 2
Intercharacter gaps
Character 1
Character 2
Character 3
11
Bar Code Types self-check

• Self-Checking a single printing defect will
  not cause a character to be transposed into
  another valid character in the same symbology
• Non Self-Checking without self checking feature

12
Bar Code Families
Most Used inTransportation Logistics -
Code 128 and EAN-128 - Code 2 of 5
Interleaved - Code 39 - Codabar (NW-7 in Japan)
13
Bar Code Families
Most Used in Retail- Code 128 and EAN-128-
Code 2 of 5 Interleaved - EAN-13 and EAN-8-
UPC-A and UPC-E with or without - ADD-ON
2 - ADD-ON 5
14
Bar Code Families
Other Older or Uncommon Bar Code
Families - Code 93 - 2 of 5 Compressed,
Industrial, 5 bars, 3 bars Matrix, BCD
Matrix, 11 Matrix, 3 bars Datalogic -
Plessey - MSI
15
Code2 of 5Interleaved
16
Code 2 of 5 IL (Interleaved)

• each digit is represented by 5 elements (all
  bars OR all spaces), 2 of which are wide (2 of 5)

17
Code 2 of 5 IL (Interleaved)

• odd digits are coded by bars while even digits
  are coded by spaces
• bars of the odd digits are interlaced
  (Interleaved) with the spaces of the even digits

18
Code 2 of 5 IL (Interleaved)

• 2 levels bar code
• numeric only
• continuous
• self-checking
• optional check digit (modulo 10)
• variable length, but always with an even number
  of digits
• use of the check digit with an even number of
  digits is possible by adding a leading 0

19
Code 2 of 5 IL (Interleaved)

• START pattern is made up of 2 narrow bars and 2
  narrow spaces

• STOP pattern is made up of one wide bar, one
  narrow space and one narrow bar

20
Code 2 of 5 IL (Interleaved)
STOP
START
21
Code 2 of 5 IL (Interleaved)

• The wide elements are N times the narrow ones
• N is the Printing Ratio and can range
• from 2 1 to 3 1 for X gt 0.508 mm (20
  mils)
• from 2.2 1 to 3 1 for X lt 0.508 mm (20
  mils)

22
Code 2 of 5 IL (Interleaved)
Length of the start 4 XLength of a
character 3 X 2 N XLength of the stop
2 X N XTotal length 4X D(3X2NX) 2X
NX X (6 N) D X (3 2 N)
X 6 N D (3 2 N)
23
Code 2 of 5 IL (Interleaved)
9 8 7 6
1 9 0 2
24
Code 2 of 5 IL (Interleaved)

• Left and Right Quiet Zones width must be at
  least 10 times the module size X

25
Code 2 of 5 IL (Interleaved)

• quite compact, but...
• ...not extremely safe
• Start and Stop pattern can easily be found
  inside a code
• variable length should be avoided (possible
  truncations with code reconstruction)
• use of check digit only reduces but does not
  eliminate the risk of misreading

26
Code 2 of 5 IL (Interleaved)

• AIM I 2/5 Uniform Symbology Specification
  says There is no guarantee that a partial
  scan of the symbol will not produce a valid read
  for an embedded symbol having fewer
  characters.It is strongly recommended that USS I
  2/5 should not be used in an application where
  the number of characters can vary

27
Code 2 of 5 IL (Interleaved)

• the number of digits can be found by the
  following easy formula

D (barcount - 7) / 5 (where 7 are the elements
of the Start and the Stop patterns and 5 are the
elements which represent each single digit)
28
Code 2 of 5 IL (Interleaved)

• but there is also a shortcut that is easier

D number of wide bars - 1 (because one belongs
to the Stop pattern)
29
Code 2 of 5 IL (Interleaved)

• a particular code Interleaved 2 of 5 is referred
  to as ITF-14 (EAN specifications)
• it is very common on carton boxes for large
  distribution
• the same code can assume other names
• DUN-14 (Delivered Unit Number)
• TUN-14 (Traded Unit Number)
• ITF-6 is similar but with 6 digits instead of 14

30
Code 2 of 5 IL (Interleaved)

• as per EAN specifications, the dimensions in the
  picture are related to Magnification Factor 1,
  where X 1.016 mm (40 mils) and H 31.8 mm

31
Code 2 of 5 IL (Interleaved)

• ITF Magnification Factors and dimensions table as
  per EAN specifications

32
Code 39
33
Code 39

• each digit is represented by 9 elements (5 bars
  and 4 intervening spaces), 3 of which are wide
  (3 of 9)

34
Code 39

• each digit is separated from the following by
  a space called Intercharacter Gap

35
Code 39

• 2 levels bar code
• self-checking
• full alphanumeric (numbers and upper case
  letters) and 7 special characters - . Space
  /
• discrete (Intercharacter Gap)
• optional check digit (modulo 43)
• variable length

36
Code 39

• START and STOP patterns are both made up of 9
  elements and represent the asterisk
  character (often included in the human readable
  part)

37
Code 39

STOP
START
38
Code 39

• The wide elements are N times the narrow ones
• N is the Printing Ratio and can range
• from 2 1 to 3 1 for X gt 0.508 mm (20
  mils)
• from 2.2 1 to 3 1 for X lt 0.508 mm (20
  mils)

39
Code 39

• The nominal width of the Intercharacter Gap
  should beminimum Xmaximum 5.3 X for
  X lt 0.25 mm or 3 X or 1.35 mm whichever is
  greater for X gt 0.25 mm

40
Code 39
Length of the start 6 X 3 N X ICGLength
of a character 6 X 3 N X ICGLength of
the stop 6 X 3 N XTotal length 6X3NX
D(6X3NX) 6X3NX (D1) ICG
X126ND(63N)(D1)ICG if ICG
X X136N7D3DN
41
Code 39
B A R
42
Code 39

• Left and Right Quiet Zones width must be at
  least 10 times the module size X

43
Code 39

• the number of digits can be found by the
  following easy formula

D (barcount - 19) / 10 (where 19 are the
elements of the Start and the Stop patterns plus
one Intercharacter Gap and 10 are the elements
which represent each single digit plus the
Intercharatcter Gap)
44
Code 39 Full ASCII

• Code 39 FULL ASCII featureit is possible to
  encodethe entire ASCII 128character set by
  usingtwo-characters sequencesmade up of one of
  thestandard code 39 symbols(/) followed by
  oneof the 26 letters

45
Code 128
46
Code 128

• 4 levels bar code
• self-checking
• continuous
• variable length
• alphanumeric (128 ASCII characters)
• check digit is always included (modulo 103)

47
Code 128

• 3 alternate character sets A, B and C are
  available (see coding table)
• each set has its own start pattern
• it is possible to switch from one set to
  another inside a code by the use of the shift
  character
• the stop pattern is always the same

48
Code 128
STOP
START set A
STOP
START set B
STOP
START set C
49
Code 128

• the start pattern, each character and the
  check digit are represented by 6 elements with
  a width of 11 modules
• the stop pattern is represented by 7 elements
  with a width of 13 modules

50
Code 128
1 2 3 4 5 6 7 8 9 10 11
12 13
START CHAR CHECK
STOP
51
Code 128 BarCount and Number of Digits
A very important parameter is the BarCount
(BC).From the value of the BarCountit is
possible to calculatethe real number of
charactersinside the code by thefollowing
formula D (BC - 19) / 6
52
Code 128 Total Length
Length of the start (A, B, C) 11 XLength of a
character 11 XLength of the check digit
11 XLength of the stop 13 XTotal
length L X (35 11 D)
53
Code 128 Total Length
From the total bar code length L(quite zones not
included)it is very easy to calculatethe module
size X L / (35 11 D)
54
Code EAN-128
55
EAN-128

• same as Code 128, but with FNC1 as first
  character
• can use AI (Application Identifiers)

56
A comparison betweenCode 2/5 Interleaved Code
39Code 128
57
I 2/5 - 39 - 128
58
I 2/5 - 39 - 128
Some considerations

• With the same number of digits and the same
  module size, Code 128 set C is more compact
  than I 2/5
• Code 39 is the widest
• Code 128 already includes a check digit
• Code 128 is a 4 level bar code, thus requires
  more printing accuracy with respect to I 2/5 and
  39
• With variable length, Code 128 is more error
  proof than I 2/5 (truncations)

59
EAN European Article NumberUPC Universal Product
CodeJAN Japan Article Number
60
EAN-13
61
EAN-13

• 4 levels bar code
• numeric only
• continuous
• self-checking
• check digit is always included
• fixed length 13 (121) digits

62
EAN-13 Dimensions

• Nominal dimensions of the code are defined with
  reference to a module size of X 0.33 mm,
  named Magnification Factor 1 (100)
• Valid range of magnifications can vary
  between 0.8 (80) and 2 (200), thus allowing a
  module size (X) range between 0.264 mm and 0.66
  mm
• All the dimensions of the code (in particular
  the bars height) must vary proportionally
  according to the Magnification Factor

63
EAN-13 Dimensions

• Dimensions are in mm and are referred to
  Magnification Factor 1 (X 0.33 mm)

64
EAN-13 Dimensions

• An alternative way to define the code dimensions
  is by the SC factor SC Factor Magnification
  Factor 0 0.8 1 0.9 2 1.0 3 1.1
  4 1.2 5 1.4 6 1.5 7 1.7 8
  1.85 9 2.0

65
EAN-13 Structure
66
EAN-13 Structure

• each of the 12 digits is represented by 4
  elements for a total length of 7 modules
• there are 2 guard patterns on the left and on
  the right of 3 elements (3 modules
  bar-space-bar)
• there is a centre pattern of 5 elements (5
  modules space-bar-space-bar-space)

67
EAN-13 Structure
gt

• left Quiet Zone is 11 modules wide
• right Quiet Zone is 7 modules wide
• BarCount is fixed to 59 (BC35341259)
• the length of the code is LX95 (without QZ)

68
EAN-13 Structure

• the first 6 digits on the left are coded with
  a variable sequence of set A (odd parity) or
  set B (even parity) that depends on the
  13th digit of data
• this is why for this part we talk about
  variable parity

69
EAN-13 Structure

• the second 6 digits on the right are all
  coded with set C (even parity)
• this is why for this part we talk about fixed
  parity
• odd or even parity of a set is given by the
  number 1s in each digit

70
EAN-13 Structure

• the 13th digit defines the sequence of set A or
  set B used to code the 6 digits on the left

71
EAN-13 Structure

• the first 2 or 3 digits represent the country
  code in which the EAN13 code was requested or
  other particular use of the code (see ISSN or
  ISBN)

72
EAN-13 Specific Applications
ISSNInternational Standard Serial Number -
Serial Publication, Periodicals - Starts with
977ISBNInternational Standard Book Number
- Books (Bookland) - Starts with 978 or 979
73
EAN-8
74
EAN-8

• 4 levels bar code
• numeric only
• continuous
• self-checking
• fixed length 8 digits
• check digit is always included
• dimensioning considerations are the same of EAN13

75
EAN-8 Dimensions

• Dimensions are in mm and are referred to
  Magnification Factor 1 (X 0.33 mm)

76
EAN-8 Structure
77
EAN-8 Structure

• each of the 8 digits is represented by 4
  elements for a total length of 7 modules
• the left hand 4 digits are coded in set A (odd
  parity), while the right hand 4 digits are
  coded in set C (even parity)

78
EAN-8 Structure

• there are 2 guard patterns on the left and on the
  right of 3 elements (3 modules bar-space-bar)
• there is a centre pattern of 5 elements (5
  modules space-bar-space-bar-space)

79
EAN-8 Structure
gt
lt

• left Quiet Zone is 7 modules wide
• right Quiet Zone is 7 modules wide
• BarCount is fixed to 43 (BC3534843)
• the length of the code is LX67 (without QZ)

80
UPC-A
81
UPC-A

• 4 levels bar code
• numeric only
• continuous
• self-checking
• check digit is always included
• fixed length 12 digits

82
UPC-A Dimensions

• Dimensions are in mm and are referred to
  Magnification Factor 1 (X 0.33 mm)

83
UPC-A Structure
84
UPC-A Structure

• each of the 12 digits is represented by 4
  elements for a total length of 7 modules
• the left hand 6 digits are coded in set A (odd
  parity), while the right hand 6 digits are coded
  in set C (even parity)

85
UPC-A Structure

• Compatibility between EAN-13 and UPC-A is
  achieved because the EAN table for the left hand
  variable parity pattern is all A for the 13th
  digit equal to 0(the implicit leading 0 of UPC-A)

86
UPC-A Structure

• there are 2 guard patterns on the left and on the
  right of 3 elements (3 modules bar-space-bar)
• there is a centre pattern of 5 elements (5
  modules space-bar-space-bar-space)

87
UPC-A Structure

• left Quiet Zone is 9 modules wide
• right Quiet Zone is 9 modules wide
• BarCount is fixed to 59 (BC35341259)
• the length of the code is LX95 (without QZ)

88
UPC-A Structure

• digit 1 numbering system (0, 7 regular PC
  2 random weight etc.)
• digit 2-6 manufacturer ID
• digit 7-11 product ID
• digit 12 check digit (modulo 10)
• on 1/1/2005 UPC-A will be switched to EAN-13
  (UPC-13)

89
UPC-E
90
UPC-E

• 4 levels bar code
• numeric only
• continuous
• self-checking
• check digit is always included
• fixed length 6 2 digits

91
UPC-E Dimensions

• Dimensions are in mm and are referred to
  Magnification Factor 1 (X 0.33 mm)

92
UPC-E Structure
93
UPC-E Structure

• each of the 6 digits is represented by 4 elements
  for a total length of 7 modules
• the 6 digits are coded with a variable sequence
  of set A (odd parity) or set B (even parity)
  that depends on the 8th digit (the one on the
  right)
• the permutation table of set A and set B
  encodation (variable parity) is different from
  the one of EAN-13 (see EAN-UPC
  specifications for more details)
• the first digit on the left is always 0

94
UPC-E Structure

• there is a guard pattern on the left of 3
  elements (3 modules bar-space-bar)
• there is a right stop pattern of 6 elements (6
  modules space-bar-space-bar-space-bar)

95
UPC-E Structure

• left Quiet Zone is 9 modules wide
• right Quiet Zone is 7 modules wide
• BarCount is fixed to 33 (BC364633)
• the length of the code is LX51 (without QZ)

96
ADD-ON 2 and 5
97
ADD-ON 2 and ADD-ON 5

• ADD-ON 2 and ADD-ON 5 are addictional codes
  placed on the right of EAN-13 or UPC-A
• they add users information to the EAN/UPC code
• typically, they are used in magazines or
  periodicals to code the number of the item (day,
  week or month)

98
ADD-ON 2 Dimensions

• Dimensions are in mm and are referred to
  Magnification Factor 1 (X 0.33 mm)

99
ADD-ON 2 Structure

• each of the 2 digits is representedby 4 elements
  with a length of 7 modules
• use of set A or set B encodation (variable
  parity) follows this ruleCC (n4) AACC
  (n4)1 ABCC (n4)2 BACC
  (n4)3 BBwhere CC is the code content value
  and n is a positive integer number starting from
  0
• this is an implicit way to implement a check
  digit

100
ADD-ON 2 Structure

• there is a start pattern (3 elements
  bar-space-bar of 1-1-2 modules)
• there is a delineator (2 elements space-bar of
  1-1 modules) between the digits
• there is no stop guard pattern

101
ADD-ON 2 Structure

• left Quiet Zone is 7 modules wide
• right Quiet Zone is 5 modules wide
• BarCount is fixed to 13 (BC234213)
• the length of the code is LX20 (without QZ)

102
ADD-ON 5 Dimensions

• Dimensions are in mm and are referred to
  Magnification Factor 1 (X 0.33 mm)

103
ADD-ON 5 Structure

• each of the 5 digits is represented by 4
  elements with a length of 7 modules
• use of set A or set B encodation (variable
  parity) follows a complex rule (algorithm to
  calculate a number use of a table of the
  possible combinations)(see EAN specifications
  for more details)
• this is an implicit way to implement a check digit

104
ADD-ON 5 Structure

• there is a start pattern (3 elements
  bar-space-bar of 1-1-2 modules)
• there is a delineator (2 elements space-bar of
  1-1 modules) between the digits
• there is no stop guard pattern

105
ADD-ON 5 Structure

• left Quiet Zone is 9 modules wide
• right Quiet Zone is 7 modules wide
• BarCount is fixed to 31 (BC3244531)
• the length of the code is LX47 (without QZ)

106
Codabar
107
Codabar

• 2 levels bar code
• self-checking
• numeric (0-9) 6 special characters - /
  . 4 letters (A, B, C, D) as start or stop
  pattern
• discrete (Intercharacter Gap)
• optional check digit
• variable length

108
Codabar

• each character is encoded as 7 elements, 2 or 3
  of which are wide
• for this reason this code is also known, mainly
  in Japan, as NW-7 (i.e. Narrow Wide 7 elements)

109
Code 93
110
Code 93

• 4 levels bar code
• self-checking
• continuous
• variable length
• alphanumeric (128 ASCII characters)
• 2 check digits (C and K) are always included
  (modulo 47)

111
Code 93

• each character is codedas 6 elements(3 bars and
  3 spaces)for a total width of 9 modules(10 only
  for the stop pattern)
• data character bars can be 1, 2 or 3 times the
  module size
• 4 modules wide bars can only be found in the
  start and stop pattern
• like full 39 code, extended ASCII characters can
  be coded as pairs with special characters

112
WWW links
113
WWW Links

• Barcode Symbologies, basics
• http//www.semiconductor.agilent.com/barcode/sg/Mi
  sc/bc_ref.html
• http//www.adams1.com/pub/russadam/info.htmlSpecs
  
• The very beginners bar code site
• http//www.csensors.com/basic1.html
• Other sites
• http//www.ean-int.org/index800.html
• http//www.issn.org/
• http//www.isbn.spk-berlin.de/

114
and at the end
115
Summary

• Before thinking there is something wrong in the
  reader
• know very well the codes you have to read (code
  family and its parameters)
• check carefully their printing quality with a
  code verifier (NEVER judge the quality by eyes !)
• select/check the right readers configuration
• select/check the right transmission interface to
  host (serial,wedge,wand)