PDF417 (2D Barcode)

Application Areas

PDF-417 is used for encoding large amounts of data, usually up to one or two-hundred characters are encoded in a single symbol.

The PDF417 symbology is mainly used in Europe and in the United States. The 2D barcode symbology is mostly utilized in the areas of logistic applications (especially in the automotive industry), transport systems (e.g. for shipping labels), identification (e.g. driver licenses, passports) and document management.

Classification

PDF417 is a 2D barcode symbology (two-dimensional barcode) with very high data density. A single PDF417 symbol can be imagined as multiple linear bar-codes (called "rows") stacked above each other. This is the reason why the PDF417 symbology is sometimes called a "stacked linear symbology". The overall shape of a PDF417 is rectangular. The size of the symbol can be modified by the user. The ratio of the widths of the bars (or spaces) to each other encode the information in a PDF417 symbol. For that reason the printing accuracy and a suitable printer resolution are important for high quality PDF417 symbols. Pure 2-D barcode symbologies like Data Matrix or QR Code encode the information in the presence of black or white dots at specific positions - and not by using bar:space ratios.

History

PDF 417 was developed 1991 by the company Symbol. In the year 2007 the company was acquired by Motorola.

Aliases

PDF417 is also known under the names PDF-417, Portable Data File and PDF 417. The term Macro PDF (or Macro PDF417) is used when concatenating multiple PDF417 barcode symbols (see below - Structured Append).

Technical Data

• Normative standards: The normative standard for the PDF 417 barcode symbology is called ISO/IEC 15438:2001 (ISO International Standard).
• PDF417 data capacity: A single PDF417 symbol can theoretically hold up to 1850 alphanumeric characters, 2710 digits or 1108 bytes. Due to internal data compression algorithms the exact data capacity depends on the structure of the data to be encoded. The maximum PDF417 capacity is also influenced by available printing space and the printer resolution.
• The default character set is CP437.
• Error correction: PDF417 offers a built-in error correction method based on Reed-Solomon algorithms. The error correction level is adjustable by the user between level 0 (just error detection) and level 8 (maximum error correction). Recommended error correction levels are between level 2 and 5, but the optimal value depends on amount of data, printing quality of the PDF417 symbol and decoding capabilities.
• PDF417 supports 'Structured Append', in such a case the symbology is named Macro PDF417 or MacroPDF. Theoretically up to 99999 PDF417 symbols can be concatenated. If a scanner or decoder supports this feature, it returns the concatenated data content of all PDF417 symbols in the correct order.