ISO/IEC 24728:2006
(Main)Information technology — Automatic identification and data capture techniques — MicroPDF417 bar code symbology specification
Information technology — Automatic identification and data capture techniques — MicroPDF417 bar code symbology specification
ISO/IEC 24728:2006 specifies the requirements for the bar code symbology known as MicroPDF417. It specifies the MicroPDF417 symbology characteristics, data character encodation, symbol formats, dimensions, error correction rules, decoding algorithm, and a number of application parameters. MicroPDF417 is a multi-row symbology, derived from and closely based on PDF417. MicroPDF417 is designed for applications with a need for improved area efficiency but without the requirement for PDF417's maximum data capacity. A limited set of symbol sizes is available, together with a fixed level of error correction for each symbol size. Module dimensions are user-specified to enable symbol production and reading by a wide variety of techniques. Since MicroPDF417's data character encodation, its error correction method, and many of its other symbol characteristics are, and are intended to remain, identical to those of PDF417, descriptions of these characteristics are quoted verbatim from the PDF417 symbology specification (ISO/IEC 15438) wherever appropriate, or with the appropriate modifications. For ease of cross-reference, ISO/IEC 24728:2006 follows a similar document structure, with minor differences in clause/subclause numbering, to the PDF417 symbology specification.
Technologies de l'information — Techniques automatiques d'identification et de capture des données — Spécifications pour la symbologie de code à barres MicroPDF417
General Information
Standards Content (Sample)
INTERNATIONAL ISO/IEC
STANDARD 24728
First edition
2006-06-01
Information technology — Automatic
identification and data capture
techniques — MicroPDF417 bar code
symbology specification
Technologies de l'information — Techniques d'identification
automatique et de capture des données — Spécifications pour la
symbologie de code à barres MicroPDF417
Reference number
©
ISO/IEC 2006
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but
shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In
downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat
accepts no liability in this area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation
parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In
the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.
© ISO/IEC 2006
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO/IEC 2006 – All rights reserved
Contents Page
Foreword. vi
Introduction . vii
1 Scope .1
2 Normative references .1
3 Terms and definitions .2
4 Symbols, operations and abbreviated terms.4
4.1 Symbols .4
4.2 Mathematical operations.5
4.3 Abbreviated terms .5
5 Requirements.5
5.1 Symbology characteristics .5
5.1.1 Basic characteristics.5
5.1.2 Summary of additional features.6
5.2 Symbol structure .7
5.2.1 MicroPDF417 symbol parameters.7
5.2.2 Row and column combinations.9
5.2.3 Row parameters.10
5.2.4 Codeword sequence.10
5.2.5 MicroPDF417 Row Address Patterns.12
5.3 Basic encodation .14
5.3.1 Symbol character structure .14
5.3.2 Start and Stop Patterns.15
5.4 High level (data) encodation.15
5.4.1 Function codewords.15
5.4.2 Text Compaction mode .21
5.4.3 Byte Compaction mode.25
5.4.4 Numeric Compaction mode .27
5.4.5 Advice to select the appropriate compaction mode .28
5.4.6 Treatment of MicroPDF417 reserved codewords.29
5.5 Extended Channel Interpretation .29
5.5.1 Encoding the ECI assignment number.30
5.5.2 Pre-assigned and default Extended Channel Interpretations .31
5.5.3 Encoding ECI sequences within compaction modes .31
5.5.4 Post-decode protocol.33
5.6 Determining the codeword sequence.33
5.7 Error detection and correction.34
5.7.1 Number of error correction codewords.34
5.7.2 Error correction capacity .34
5.7.3 Defining the error correction codewords.35
5.8 Dimensions.35
5.8.1 Minimum width of a module (X).35
5.8.2 Row height (Y).35
5.8.3 Quiet zones.35
5.9 Defining the symbol format .35
5.9.1 Defining the aspect ratio of the module .36
5.9.2 Defining the symbol matrix of rows and columns .36
5.10 Generating the error correction codewords .37
5.11 Low level encodation .39
5.11.1 Clusters.40
© ISO/IEC 2006 – All rights reserved iii
5.11.2 Determining the symbol matrix . 40
5.11.3 Determining the values of the Row Address Patterns . 40
5.11.4 Row encoding. 46
5.12 Printing Row Address Patterns . 46
5.13 Structured Append. 47
5.13.1 Compaction modes and Structured Append. 47
5.13.2 ECIs and Structured Append . 47
5.14 User guidelines . 47
5.14.1 Human readable interpretation. 47
5.14.2 Autodiscrimination capability. 47
5.14.3 User-defined application parameters. 48
5.14.4 MicroPDF417 symbol quality . 48
5.14.5 Separation of multiple symbols. 49
5.15 Reference decode algorithm. 49
5.16 Error detection and error correction procedure . 49
5.17 Transmitted data . 49
5.17.1 Transmitted data in the basic (default) interpretation. 49
5.17.2 Transmission protocol for Extended Channel Interpretation (ECI) . 49
5.17.3 Transmitted data for Structured Append.51
5.17.4 Transmission of reserved codewords using the ECI protocol. 51
5.17.5 Symbology identifier. 51
5.17.6 Transmission using older protocols. 51
Annex A (normative) Encoding/decoding table of PDF417 symbol character bar-space sequences. 52
Annex B (normative) The default character set for Byte Compaction mode . 67
Annex C (normative) Byte Compaction mode encoding algorithm . 68
Annex D (normative) Numeric Compaction mode encoding algorithm. 70
Annex E (normative) Error correction . 72
Annex F (normative) Tables of coefficients for calculating MicroPDF417 error correction
codewords . 73
Annex G (normative) Text Compaction mode encoding algorithm. 77
Annex H (normative) Structured Append MicroPDF417 symbols . 78
H.1 Structured Append overview . 78
H.2 Structured Append syntax . 78
H.3 High level encoding considerations . 81
H.4 Encodation example . 81
H.5 Structured Append and the Extended Channel Interpretation protocol . 82
H.6 Structured Append data transmission. 83
Annex I (normative) Testing MicroPDF417 symbol quality. 86
I.1 Overview of methodology . 86
I.2 Test scans for scan reflectance profile . 86
Annex J (normative) Reference decode algorithm for MicroPDF417. 88
J.1 Phase 1: Initialization. 88
J.2 Phase 2: Filling the matrix. 89
J.3 Phase 3: Interpretation . 90
J.4 Reference line-decode algorithm . 91
Annex K (normative) Error correction procedures . 95
Annex L (normative) Symbology identifier . 97
Annex M (normative) Transmission protocol for decoders conforming with original
PDF417 standards. 98
M.1 Basic Channel Mode . 98
M.2 GLI encoded symbols. 98
M.3 Structured Append symbols. 100
M.4 Transmission of reserved codewords using the original PDF417 protocol . 101
iv © ISO/IEC 2006 – All rights reserved
M.5 Achieving compatibility between old and new PDF417 equipment .101
Annex N (informative) Algorithm to minimise the number of codewords.104
Annex O (informative) Guidelines to determine the symbol matrix.106
Annex P (informative) Calculating the coefficients for generating the error correction
codewords — worked example .107
Annex Q (informative) Generating the error correction codewords — worked example .109
Annex R (informative) Division circuit procedure for generating error correction codewords.112
Annex S (informative) Additional guidelines for the use of MicroPDF417.113
S.1 Autodiscrimination compatibility.113
S.2 Pixel-based printing .113
Bibliography .115
© ISO/IEC 2006 – All rights reserved v
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members of
ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with particular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest. Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
ISO/IEC 24728 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 31, Automatic Identification and data capture techniques.
This International Standard contains many provisions which are identical with those of ISO/IEC 15438.
vi © ISO/IEC 2006 – All rights reserved
Introduction
MicroPDF417 is a multi-row symbology, derived from and closely based on PDF417. MicroPDF417 is
designed for applications with a need for improved area efficiency but without the requirement for PDF417’s
maximum data capacity. A limited set of symbol sizes is available, together with a fixed level of error
correction for each symbol size. Module dimensions are user-specified to enable symbol production and
reading by a wide variety of techniques.
Since MicroPDF417’s data character encodation, its error correction method, and many of its other symbol
characteristics are, and are intended to remain, identical to those of PDF417, descriptions of these
characteristics are quoted verbatim from the PDF417 symbology specification (ISO/IEC 15438) wherever
appropriate, or with the appropriate modifications. For ease of cross-reference, this International Standard
follows a similar document structure, with minor differences in clause/subclause numbering, to ISO/IEC 15438.
© ISO/IEC 2006 – All rights reserved vii
INTERNATIONAL STANDARD ISO/IEC 24728:2006(E)
Information technology — Automatic identification and data
capture techniques — MicroPDF417 bar code symbology
specification
1 Scope
This International Standard specifies the requirements for the bar code symbology known as MicroPDF417. It
specifies the MicroPDF417 symbology characteristics, data character encodation, symbol formats, dimensions,
error correction rules, decoding algorithm, and a number of application parameters.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO/IEC 646:1991, Information technology — ISO 7-bit coded character set for information interchange
ISO/IEC 8859-1, Information technology — 8-bit single-byte coded graphic character sets — Part 1: Latin
alphabet No. 1
ISO/IEC 15415, Information technology — Automatic identification and data capture techniques — Bar code
print quality test specification — Two-dimensional symbols
ISO/IEC 15417, Information technology — Automatic identification and data capture techniques — Bar code
symbology specification — Code 128
ISO/IEC 15418, Information technology — EAN/UCC Application Identifiers and Fact Data Identifiers and
Maintenance
ISO/IEC 15424, Information technology — Automatic identification and data capture techniques — Data
Carrier Identifiers (including Symbology Identifiers)
ISO/IEC 24723, Information technology — Automatic identification and data capture techniques — EAN.UCC
Composite bar code symbology specification
ISO/IEC 19762-1, Information technology — Automatic identification and data capture (AIDC) techniques —
Harmonized vocabulary — Part 1: General terms relating to AIDC
ISO/IEC 19762-2, Information technology — Automatic identification and data capture (AIDC) techniques —
Harmonized vocabulary — Part 2: Optically readable media (ORM)
AIM Inc. International Technical Standard: ITS/04-001, Extended Channel Interpretations — Part 1:
Identification Schemes and Protocols
GS1 General Specification
Published by AIM Global, 125 Warrendale-Bayne Road, Suite 100, Warrendale, PA 15086, USA.
Published by GS1, Blue Tower, Avenue Louise 326, bte 10, B-1050 Brussels, Belgium.
© ISO/IEC 2006 – All rights reserved 1
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 19762-1, ISO/IEC 19762-2 and
the following apply.
3.1
application identifier
sequence of 2 to 4 digits, used to define the nature or use of the subsequent data characters, in accordance
with ISO/IEC 15418 and the GS1 General Specification
3.2
bar-space sequence
sequence which represents the module widths of the elements of a symbol character
3.3
basic channel mode
standard system for encoding and transmitting bar code data where data message bytes are output from the
decoder but no control information about the message is transmitted
3.4
cluster
any of three mutually exclusive subsets of PDF417 symbol characters, also used in MicroPDF417; the symbol
characters in a given cluster conform with particular structural rules which are used in decoding the symbology
3.5
compaction mode
any of three data compaction algorithms in PDF417 (Text, Numeric and Byte Compaction modes), also used
in MicroPDF417, which are used to map 8-bit data bytes efficiently to PDF417 codewords
3.6
e-distance
measurement from the leading edge of one element to the leading edge of the next element, or from the
trailing edge of an element to the trailing edge of the next element, in a symbol character or Row Address
Pattern
3.7
error correction codeword
codeword which encodes a value derived from the error correction codeword algorithm to enable decode
errors to be detected and, depending on the number of error correction codewords, to be corrected
3.8
Extended Channel Interpretation
ECI
procedure within some symbologies, including MicroPDF417, to replace the default interpretation with another
interpretation in a reliable manner
NOTE The interpretation intended prior to producing the symbol can be retrieved after decoding the scanned symbol
to recreate the data message in its original format.
3.9
extended channel model
system for encoding and transmitting both data message bytes and control information about the message,
the control information being communicated using Extended Channel Interpretation (ECI) escape sequences
3.10
family
set of MicroPDF417 symbol versions sharing the same number of columns and the same RAP rotation
2 © ISO/IEC 2006 – All rights reserved
3.11
function codeword
codeword which initiates a particular operation within a symbology, for example to switch between data
encoding sets, to invoke a compaction scheme, to program the reader, or to invoke Extended Channel
Interpretations
3.12
Global Label Identifier
GLI
procedure in the PDF417 symbology which behaves in a similar manner to Extended Channel Interpretation
NOTE The GLI system was the symbology-dependent precursor to the symbology-independent ECI system.
3.13
macro character
character representing a predefined sequence of data characters (e.g. an industry-specific message header)
used to reduce the number of symbol characters needed to encode data in a symbol using certain structured
formats
3.14
Mode Latch codeword
codeword which is used to switch from one mode to another mode, which stays in effect until another latch or
shift codeword is implicitly or explicitly brought into use, or until the end of the symbol is reached
3.15
Mode Shift codeword
codeword which is used to switch from one mode to another for one codeword, after which encoding returns
to the original mode
3.16
RAP rotation
difference between the number designating a Center or Right Row Address Pattern and the number
designating the nearest Row Address Pattern to the left, in the same row of a symbol
3.17
Row Address Patterns
special patterns made up of three bars and three spaces occupying ten modules that serve both as start or
(with the stop bar) stop patterns and as row indicators in MicroPDF417 symbols
3.18
stop bar
single-module bar, adjoining the rightmost Row Address Pattern, which forms the right boundary of the symbol
3.19
Structured Append
procedure within the MicroPDF417 symbology to distribute data logically from a computer file across a
number of related symbols
NOTE 1 This procedure is identical to the Macro PDF417 feature of PDF417.
NOTE 2 The procedure considerably extends the data capacity beyond that of a single symbol.
3.20
UCC/EAN-128
subset of Code 128 symbols as defined in ISO/IEC 15417, reserved for use in accordance with GS1 General
Specification
© ISO/IEC 2006 – All rights reserved 3
4 Symbols, operations and abbreviated terms
4.1 Symbols
For the purposes of this document, the following mathematical symbols apply. There are some cases where the
symbols below have been used in a different manner in an equation. This has been done for consistency with a
more general use of the notation and is always clearly defined in the text.
b the element width in a symbol character
c number of columns in the symbol in the data region (excluding Row Address Patterns)
d data codeword including ECI Descriptor and all function codewords
E error correction codeword
e an edge to similar edge dimension in a symbol character
f number of substitution errors
F row number
H height of symbol including quiet zone
K cluster number
k number of error correction codewords
L number of erasures
m number of source data codewords (including the codeword in the ECI Descriptor position but prior to
the addition of any pad codewords)
n total number of data codewords (including ECI Descriptor and pad codewords)
p pitch or width of a symbol character
Q horizontal quiet zone
H
Q vertical quiet zone
V
r number of rows in the symbol
W width of symbol including quiet zone
X X-dimension or module width
Y module height (also called row height)
4 © ISO/IEC 2006 – All rights reserved
4.2 Mathematical operations
For the purposes of this document, the following mathematical operations apply.
div is the integer division operator, rounding down
INT is the integer value i.e. where a number is rounded down to its whole number component, ignoring its
decimal fractions
mod is the positive integer remainder after division. If the remainder is negative, then add the value of the
divisor in order to make the result positive. For example, the remainder of –29 160 divided by 929 is
–361, which when added to 929 yields 568
4.3 Abbreviated terms
For the purposes of this document, the following abbreviated terms apply.
AI Application Identifier
EC Error Correction
ECI Extended Channel Interpretation
GLI Global Label Identifier
RAP Row Address Pattern
5 Requirements
5.1 Symbology characteristics
5.1.1 Basic characteristics
MicroPDF417 is a multi-row symbology which may be utilized by applications needing to encode a moderate
amount of data in a two-dimensional symbol (up to 150 bytes, 250 alphanumeric characters, or 366 numeric
digits), and when minimizing symbol size is a primary concern. MicroPDF417 is identical to PDF417 in terms
of its encodation modes, error correction method, and symbol character sets. However, MicroPDF417
replaces PDF417’s 17-module-wide start/stop patterns and left/right row indicators with a unique set of 10-
module-wide Row Address Patterns, which were designed both to reduce overall symbol width and to facilitate
linear scanning at row heights as low as 2X. MicroPDF417, unlike PDF417, may only be printed in certain
defined combinations of r (number of rows), c (number of columns), and k (number of error correction
codewords), up to a maximum of four data columns by 44 rows (see 5.2.2).
MicroPDF417 has the following basic characteristics:
a) Encodable character set:
1) Text Compaction mode (see 5.4.2) permits all printable ASCII characters to be encoded, i.e.
values 32 to 126 inclusive in accordance with ISO/IEC 646, as well as selected control characters.
2) Byte Compaction mode (see 5.4.3) permits all 256 possible 8-bit byte values to be encoded. This
includes all ASCII characters value 0 to 127 inclusive and provides for international character set
support.
3) Numeric Compaction mode (see 5.4.4) permits efficient encoding of numeric data strings.
4) Up to 811 800 different character sets or data interpretations.
5) Various function codewords for control purposes.
© ISO/IEC 2006 – All rights reserved 5
b) Symbol character structure: (n, k, m) characters of 17 modules (n), 4 bar and 4 space elements (k), with
the largest element 6 modules wide (m).
c) Maximum possible number of data characters per symbol (for a maximum size MicroPDF417 symbol):
125 data codewords which can encode
1) Text Compaction Mode: 250 characters (2 data characters per codeword).
2) Byte Compaction mode: 150 characters (1,2 data characters per codeword).
3) Numeric Compaction mode: 366 characters (2,93 data characters per codeword).
d) Symbol Size:
1) Number of rows: 4 to 44 (available in defined combinations with number of columns).
2) Number of data columns: either one, two, three, or four
3) Width in modules: 40X, 57X, 84X, or 101X including quiet zones
4) Maximum codeword capacity: 176 codewords.
5) Maximum data codeword capacity: 125 codewords.
e) Number of error correction codewords: fixed for each available row/column combination, ranging from 7
to 50 codewords per symbol and reserving from 28% to 67% of codewords for error detection and
correction, depending on symbol size.
f) Non-data overhead: per row: 23 modules for the one- and two-column versions; 33 modules for the three-
or four-column version, including quiet zones.
g) Code type: continuous, multi-row bar code symbology
h) Character self-checking: Yes.
i) Bi-directionally decodable: Yes.
5.1.2 Summary of additional features
The following are additional features in MicroPDF417:
a) Data compaction: Three schemes are defined to compact a number of data characters into codewords.
Generally data is not directly represented on a one character for one codeword basis (see 5.4.2 to 5.4.4).
b) Extended Channel Interpretations: These mechanisms allow up to 811 800 different data character
sets or interpretations to be encoded (see 5.5).
c) Structured Append: MicroPDF417 uses the Macro PDF417 mechanism for Structured Append. This
mechanism allows files of data to be represented logically and consecutively in a number of
MicroPDF417 symbols. Up to 99 999 different MicroPDF417 symbols can be so linked or concatenated
and be scanned in any sequence to enable the original data file to be correctly reconstructed (see 5.13).
d) Edge to edge decodable: MicroPDF417 can be decoded by measuring elements from edge to similar
edge (see 5.3.1).
e) Cross-row scanning: The combination of three characteristics in MicroPDF417 facilitates cross-row
scanning:
• being synchronised horizontally, or self clocking
• row identification
• being vertically synchronised, by using the cluster values to achieve local row discrimination.
6 © ISO/IEC 2006 – All rights reserved
This combination allows a single linear scan to cross a number of rows and achieve a partial decode of
the data so long as at least one complete symbol character per row is decoded into its codeword. The
decoding algorithm can then place the individual codewords into a meaningful matrix.
f) Code 128 emulation codewords: special codewords may be used at the start of a MicroPDF417 symbol
as a signal to the decoder to transmit the symbol’s data as if it were encoded in a Code 128 symbol. The
Symbology Identifier of the resulting transmission can thus signal the presence of an implied FNC1 flag,
for special applications (see 5.4.1.5).
5.2 Symbol structure
5.2.1 MicroPDF417 symbol parameters
Each MicroPDF417 symbol consists of a stack of vertically-aligned rows (with a minimum of 4 and maximum
of 44 rows); the allowable numbers of rows are specified separately for each of the one-, two-, three- or four-
column versions. Each row shall include a minimum of 1 symbol character and a maximum of 4 symbol
characters, excluding the Row Address Pattern columns. The symbol shall include a quiet zone on all four
sides.
Figure 1 shows sample one-, two-, three-, and four-column MicroPDF417 symbols, each with twenty rows.
© ISO/IEC 2006 – All rights reserved 7
Data Codeword Column
1 Column by 20 Rows,
Encoding:
'ABCDEFGHIJKLMNOPQRSTUV'
Row Address Patterns
2 Columns by 20 Rows,
Encoding:
'ABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGH
IJKLMNOPQRSTUVWXYZABCD'
Data Codeword Columns
3 Columns by 20 Rows,
Encoding:
'ABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGH
IJKLMNOPQRSTUVWXYZABCDEFGHIJKLMN'
Row Address Patterns
4 Columns by 20 Rows,
Encoding:
'ABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGH
IJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQ
RSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXY
ZAB'
Data Codeword Columns
Figure 1 — Four MicroPDF417 symbols
8 © ISO/IEC 2006 – All rights reserved
5.2.2 Row and column combinations
MicroPDF417 symbols shall conform with certain predefined combinations of numbers of rows, columns, and
number of error-correction codewords. These versions are defined in Table 1.
Table 1 — MicroPDF417 version characteristics
Number of Total Number Number Max Max Symbol Symbol
Number Number % of Max Data
Data CWs in of of CWs Alpha Digits Width, Height,
of Rows of EC CWs for Bytes
Columns Data non-EC for Data chars (Note in X in X
(r) CWs (k)
EC (Note 2)
(c) Region CWs (Note 1) (Note 3) 3) (Note 4) (Note 5)
1 11 11 7 64 4 3 3 6 8 40 24
1 14 14 7 50 7 6 7 12 17 40 30
1 17 17 7 41 10 9 10 18 26 40 36
1 20 20 8 40 12 11 13 22 32 40 42
1 24 24 8 33 16 15 18 30 44 40 50
1 28 28 8 29 20 19 22 38 55 40 58
2 8 16 8 50 8 7 8 14 20 57 18
2 11 22 9 41 13 12 14 24 35 57 24
2 14 28 9 32 19 18 21 36 52 57 30
2 17 34 10 29 24 23 27 46 67 57 36
2 20 40 11 28 29 28 33 56 82 57 42
2 23 46 13 28 33 32 38 64 93 57 48
2 26 52 15 29 37 36 43 72 105 57 54
3 6 18 12 67 6 5 6 10 14 84 14
3 8 24 14 58 10 9 10 18 26 84 18
3 10 30 16 53 14 13 15 26 38 84 22
3 12 36 18 50 18 17 20 34 49 84 26
3 15 45 21 47 24 23 27 46 67 84 32
3 20 60 26 43 34 33 39 66 96 84 42
3 26 78 32 41 46 45 54 90 132 84 54
3 32 96 38 40 58 57 68 114 167 84 66
3 38 114 44 39 70 69 82 138 202 84 78
3 44 132 50 38 82 81 97 162 237 84 90
4 4 16 8 50 8 7 8 14 20 101 10
4 6 24 12 50 12 11 13 22 32 101 14
4 8 32 14 44 18 17 20 34 49 101 18
4 10 40 16 40 24 23 27 46 67 101 22
4 12 48 18 38 30 29 34 58 85 101 26
4 15 60 21 35 39 38 45 76 111 101 32
4 20 80 26 33 54 53 63 106 155 101 42
4 26 104 32 31 72 71 85 142 208 101 54
4 32 128 38 30 90 89 106 178 261 101 66
4 38 152 44 29 108 107 128 214 313 101 78
4 44 176 50 28 126 125 150 250 366 101 90
CW = Codeword; EC = Error correction
NOTE 1 Excludes EC codewords and codeword in the ECI Descriptor position
NOTE 2 Assumes remaining in default Byte Compaction Mode (see 5.4)
NOTE 3 Assumes that a Latch to Text or Numeric Compaction mode replaces the ECI Descriptor
NOTE 4 Including 1X quiet zones on either side
NOTE 5 Assumes Y = 2X; includes 1X quiet zones at top and bottom
© ISO/IEC 2006 – All rights reserved 9
5.2.3 Row parameters
Each row within a MicroPDF417 symbol has the following structure (examples are shown in Figure 1):
1. a leading Quiet Zone (see 5.8.3);
2. a Left MicroPDF417 Row Address Pattern (see 5.2.5);
3. one of the following:
a) for the one-column version, one PDF417 codeword, or
b) for the two-column version, two PDF417 codewords, or
c) for the three-column version, one PDF417 codeword followed by a Center Row
Address Pattern (see 5.2.5) and two more PDF417 codewords, or
d) for the four-column version, two PDF417 codewords followed by a Center Row
Address Pattern and two more PDF417 codewords;
4. a Right MicroPDF417 Row Address Pattern;
5. a one-module stop bar; (see 5.2.5);
6. a trailing Quiet Zone (see 5.8.3).
All MicroPDF417 symbols contain at least two Row Address Pattern columns (separated from each other by
one or two data columns), and every codeword column is adjacent to at least one Row Address Pattern
column.
5.2.4 Codeword sequence
5.2.4.1 Overall sequence
A MicroPDF417 symbol may contain up to 176 symbol characters or codewords. Symbol character is the
more appropriate term to refer to the printed bar/space pattern; codeword is more appropriate for the numeric
value of the symbol character. The codewords shall follow this sequence:
a. The first codeword in a MicroPDF417 symbol may have a special meaning as an ECI Descriptor (see
5.2.4.2).
b. The data codewords shall follow, from the most significant encodable character. Codewords with
values above 899 may be inserted to change the compaction mode, to perform other special functions,
or to indicate ECIs.
c. Pad codewords as needed to enable the codeword sequence to be represented in the number of rows
and columns specified for the selected MicroPDF417 version (usually the smallest of sufficient
capacity).
d. An optional Structured Append Control Block.
e. Error correction codewords for error detection and correction.
The codewords are arranged with the most significant codeword at the upper left corner of the matrix, and are
encoded from left to right, top row to bottom. In the three- and four-column versions, the center Row Address
Pattern does not change the codeword sequence (that is, the first three or four codewords of the sequence
are placed left to right in the first row, the Center Row Address Pattern being inserted before the last two
codewords in the row; the next three or four codewords are placed in the same manner in the second row,
and so on). Figure 2 illustrates in layout format the sequence for a 14-row, two-column MicroPDF417 symbol.
10 © ISO/IEC 2006 – All rights reserved
Left RAP d d Right RAP
1 18 17 1
Left RAP d d Right RAP
2 16 15 2
Left RAP d d Right RAP
3 14 13 3
Left RAP d d Right RAP
4 12 11 4
Left RAP d d Right RAP
5 10 9 5
Left RAP d d Right RAP
6 8 7 6
Left RAP d d Right RAP
7 6 5 7
Left RAP d d Right RAP
8 4 3 8
Left RAP d d Right RAP
9 2 1 9
Left RAP d e Right RAP
10 0 8 10
Left RAP e e Right RAP
11 7 6 11
Left RAP e e Right RAP
12 5 4 12
Left RAP e e Right RAP
13 3 2 13
Left RAP e e Right RAP
14 1 0 14
where:
RAP is the appropriate Left or Right Row Address Pattern for row j of this symbol version
j
d = first codeword (ECI Descriptor or function codeword)
d - d = encoded data, together with pad codewords if required
17 0
e - e = Error Correction codewords
8 0
Figure 2 — MicroPDF417 example of symbol layout schematic
The rules and advice for structuring the matrix are included in 5.9.
5.2.4.2 ECI Descriptor codeword
Because MicroPDF417 is intended for applications where symbol size is critical, it is expected that
MicroPDF417 will frequently be used in conjunction with a Transformation ECI appropriate for the data
requirements of the application. MicroPDF417 supports efficient encoding of a single Transformation ECI
sequence at the start of each data stream by defining an optional ECI Descriptor codeword that can be
encoded at the start of the first symbol of each MicroPDF417-encoded data stream. This Transformation ECI
co-exists with the Interpretative ECI (whether default or explicitly encoded) currently in effect, since
Interpretative ECIs and Transformation ECIs have independent scopes.
If the input to the MicroPDF417 encoder calls for a Transformation ECI in the range 000900 to 001799 to be
encoded at the start of the symbol (or at the start of the first symbol of a Structured Append series), then the
MicroPDF417 encoder may encode that ECI in shortened form as a single data codeword (range 0 to 899), as
the first codeword in the data region. This codeword is calculated as (ECI_number MOD 900). Otherwise the
© ISO/IEC 2006 – All rights reserved 11
MicroPDF417 encoder shall encode a codeword of 900 or greater as the first codeword, operating as a
standard MicroPDF417 function codeword (see 5.4.1).
EXAMPLE A Transformation ECI 001002 needs to precede the data to be encoded. It can be efficiently encoded at
the start of a MicroPDF417 symbol using the single codeword 102 (because 102 is the third codeword of the standard
PDF417 representation [926] [0] [102] of that ECI. (See 5.5.1)).
Where no ECI needs to be encoded at the start of the symbol and the data is most
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.
Loading comments...