DD ENV 12925:1998

Contents
National Foreword
Foreword
Introduction
1. Scope
2. Normative References
3. Definitions, Mathematical Symbols and Abbreviations
    3.1 Definitions
    3.2 Mathematical Symbols and Operations
    3.3 Abbreviations
4. Requirements
    4.1 Symbology Characteristics
         4.1.1 Basic Characteristics
         4.1.2 Summary of Additional Features
    4.2 Symbol Structure
         4.2.1 'PDF417' Symbol Parameters
         4.2.2 Row Parameters
         4.2.3 Codeword Sequence
    4.3 Basic Encodation
         4.3.1 Symbol Character Structure
         4.3.2 Start and Stop Characters
    4.4 High Level (Data) Encodation
         4.4.1 Function Codewords
         4.4.2 Text Compaction Mode
         4.4.3 Byte Compaction Mode
         4.4.4 Numeric Compaction Mode
         4.4.5 Advice to Select the Appropriate
                Compaction Mode
         4.4.6 Treatment of 'PDF417' Reserved Codewords
    4.5 Extended Channel Interpretation
         4.5.1 Encoding the ECI Assignment Number
         4.5.2 Pre-assigned Extended Channel
                Interpretations
         4.5.3 Encoding ECI Sequences Within Compaction
                Modes
         4.5.4 Post-Decode Protocol
    4.6 Determining the Codeword Sequence
    4.7 Error Detection and Correction
         4.7.1 Error Correction Level
         4.7.2 Error Correction Capacity
         4.7.3 Defining the Error Correction Codewords
    4.8 Dimensions
    4.9 Defining the Symbol Format
         4.9.1 Defining the Aspect Ratio of the Module
         4.9.2 Defining the Symbol Matrix of Rows and
                Columns
    4.10 Generating the Error Correction Codewords
    4.11 Low Level Encodation
         4.11.1 Clusters
         4.11.2 Determining the Symbol Matrix
         4.11.3 Determining the Values of the Left and
                Right Row Indicators
         4.11.4 Row Encoding
    4.12 Compact 'PDF417'
    4.13 Macro 'PDF417'
         4.13.1 Compaction Modes and Macro 'PDF417'
         4.13.2 ECIs and Macro 'PDF417'
    4.14 User Guidelines
         4.14.1 Human Readable Interpretation
         4.14.2 Autodiscrimination Capability
         4.14.3 User-defined Application Parameters
         4.14.4 'PDF417' Symbol Quality
    4.15 Reference Decode Algorithm
    4.16 Error Detection and Error Correction Procedure
    4.17 Transmitted Data
         4.17.1 Transmitted Data in the Basic (Default)
                Interpretation
         4.17.2 Transmission Protocol for Extended
                Channel Interpretation (ECI)
         4.17.3 Transmitted Data for Macro 'PDF417'
         4.17.4 Transmission of Reserved Codewords Using
                the ECI Protocol
         4.17.5 Symbology Identifier
         4.17.6 Transmission Using Older Protocols
Annex A (normative) Encoding/Decoding Table of 'PDF417'
         Symbol Character X-Sequences
Annex B (normative) The Default Character Set for Byte
         Compaction Mode
Annex C (normative) Base 256 to Base 900 Conversion
         Algorithm
Annex D (normative) Base 10 to Base 900 Conversion
         Algorithm
Annex E (normative) User Selection of Error Correction
E.1 Recommended Error Correction Level
E.2 Other User Consideration of the Error Correction
         Level
Annex F (normative) Tables of Coefficients for
         Calculating 'PDF417' Error Correction Codewords
Annex G (normative) Compact 'PDF417'
Annex H (normative) Macro 'PDF417'
H.1 Macro 'PDF417' Overview
H.2 Macro 'PDF417' Syntax
         H.2.1 The Segment Index
         H.2.2 File ID Field
         H.2.3 Optional Fields
         H.2.4 Macro 'PDF417' Terminator
H.3 High Level Encoding Considerations
H.4 Encodation Example
H,5 Macro 'PDF417' and Extended Channel
         Interpretation
         H.5.1 Macro 'PDF417' with ECI 000000 AND 000001
         (GLI 0 and 1)
         H.5.2 Macro 'PDF417' and Other ECIs
H.6 Macro 'PDF417' Data Transmission
         H.6.1 Operating in Buffered Mode
         H,6,2 Operating in Unbuffered Mode
         H.6.3 Reset-to-Zero Transmissions
Annex J (normative) Testing 'PDF417' Symbol Quality
J.1 Grade Based on Start and Stop Characters
J.2 Grade Based on Symbol Characters
J.3 Overall Symbol Grade
Annex K (normative) Reference Decode Algorithm for
         'PDF417'
K.1 Initialisation
K.2 Reference Decode Algorithm for Line Decoding
K.3 Filling the Matrix
K.4 Interpretation
Annex L (normative) Error Correction Procedures
Annex M (normative Symbology Identifier
Annex N (normative) Transmission Protocol for Decoders
         Conforming to Earlier 'PDF417' Standards
N.1 Basic Channel Encodation
N.2 GLI Encoded Symbols
N.3 Macro 'PDF417' Symbols
         N.3.1 Transmission in Buffered Mode
         N.3.2 Transmission in Unbuffered Mode
N.4 Transmission of Reserved Codewords Using the
         Original 'PDF417' Protocol
N.5 Achieving Compatibility Between Old and New
         'PDF417' Equipment
         N.5.1 Encoders
         N.5.2 Decoders
Annex P (informative) Algorithm to Minimise the Number of
         Codewords
Annex Q (informative) Autodiscrimination Compatibility
Annex R (informative) Guidelines to Determine the Symbol
         Matrix
Annex S (informative) Calculating the Coefficients for
         Generating the Error Correction Codewords - Worked
         Example
Annex T (informative) Generating the Error Correction
         Codewords - Worked Example
Annex U (informative) Division Circuit Procedure for
         Generating Error Correction Codewords
Annex V (informative) Bibliography

Gives the requirements for the bar code symbology which is known as 'PDF417'. It specifies 'PDF417' symbology characteristics, data character encodation, symbol dimensions, tolerances, formats, decoding algorithm, error correction rules, and a number of application parameters.