Barcode Introduction > PDF-417
Overview of PDF-417
PDF-417 is a continuous, variable-length, and two-dimensional barcode type with high data capacity, which was invented by Dr.Yinjun P.Wang at Symbol Technologies in 1991. It is also called as Portable Data File 417, PDF 417, PDF-417 Truncated. And this barcode type can be decoded bidirectionally like GS1 128.
The character set of PDF-417 contains three compactions: text compaction (ASCII 0 - 255), byte compaction (ASCII 9, 10, 13 & 32 - 127), and numeric compaction (digits 0 - 9). And the number of data characters per PDF-417 symbol is shown at the following table:
PDF-417 Symbology At error correction level 0 At the minimum recommended error correction level
Text Compaction mode 1,726 characters 1,850 characters
Byte Compaction mode 1,033 characters 1,108 characters
Numeric Compaction mode 2,528 characters 2,710 characters
PDF-417 is commonly used in transport, inventory management, etc, which is one of the formats (along with Data Matrix) that can be used to print postage accepted by the United States Postal Service. Besides, barcode PDF417 is also selected by the airline industry's Bar Coded Boarding Pass standard (BCBP) for paper boarding passes.
Generate PDF-417 Barcodes
PDF-417 Generator for .NET - .NET Barocde Component for PDF-417 generation in Windows and Web Applications

PDF-417 Generator for Winforms - .NET Barocde Component for PDF-417 generation in .NET Winforms, C#.NET and VB.NET

PDF-417 Generator for Java - Java Barcode Component for PDF-417 generation in Java

PDF-417 Generator for Android - Smartphone Barcode Component for PDF-417 generation in Android system

PDF-417 Generator for Word - Word Barcode Component for PDF-417 generation in MS-Word

PDF-417 Generator for Excel - Excel Barcode Component for PDF-417 generation in MS-Excel
Structure of PDF-417
Each pattern of PDF-417 consists of 4 bars and spaces. And each pattern is 17 units long. That is why we called it PDF-417. This barcode symbol consists of 3-90 rows. And each row is constructed of 4 parts: start & stop quiet zone, start & stop pattern, left and right row indicator codewords, and message data.
Quiet Zone: It is a mandated minimum amount of white space at the beginning and end of the bar code.
Start & Stop Pattern: This is used to identify the format as PDF417.
Row Indicator Codewords: This contains information about the row such as the row number and error correction level.
Message Data: This contains less than or equal to 30 data codewords, which are a group of bars and spaces representing one or more numbers, letters, or other symbols.
Features of PDF-417

PDF-417 Error Correction Levels (ECL)

PDF-417 error correction is based on Reed-Solomon algorithm. It has 8 levels of error correction and the recommended minimum level of ECL is level 2. And when PDF-417 is created, 2 to 512 error correction codewords will be added.

PDF-417 Extended Channel Interpretations (ECI)

PDF-417 ECI protocol allows the output data stream to have interpretations different from that of the default character set. An ECI codeword can be used to switch to a particular interpretation, which actually can stay in effect until another ECI codeword is clearly brought into use or until the end of the data.

Compact PDF-417

Compact PDF-417 means the overhead reduction version. To meet some specified industrial applications, Compact PDF-417 is recommended to be used based on that space is a prime consideration and that symbol is not damaged. At that time, the right row indicators can be omitted, and the stop pattern may be reduced.

PDF-417 Encoding Functions

Apart from three compaction types, PDF-417 is allowed to encode ASCII Functions using the tilde (~) in all KeepAutomation products. When the tilde (~) function is used, PDF-417 can encode the Application Identifiers (AI) and it will be compatible with GS1 specification.