PDF417 bar code
The 2D codes used in payment transactions generally have a square structure and consist of a two-dimensional bit pattern. The situation is different with the PDF417 2D code, which is used in international payment transactions for the International Payment Instructions( IPI), but is also used by the Association of Statutory Health Insurance Physicians for medical forms and for electronic tax returns.
The PDF417 is a stacked code or codablock, a multiple stacked bar code, also called a stack code, which consists of several bar codes arranged one below the other. In terms of structure, the PDF417 code, which has been standardized by ISO/ IEC under FCD 15438, consists of a minimum of 3 and a maximum of 90 individual bar code rows arranged one below the other. Depending on the selected operating mode, each PDF417 code field can consist of 1,100 bytes, 1,800 ASCII characters or 2,700 digits. Each individual row is defined by a starting quiet zone, the start pattern, the row indicators, the data, the stop pattern and the trailing quiet zone. The data field can consist of one or a maximum of 30 characters. Since both the number of rows and the size of the data field are variable, the length-to-height ratio of the PDF417 code field is also different.
The PDF417 code has an error correction, which means that even damaged code fields can be read. The error rate of PDF417 is very good and in the worst case it is one error within 10 MB of data, in the best case it is one error within 600 MB . It is mainly used in the areas of transport and logistics.
The PDF417 code is also available in a more compact version with a more efficient use of space as Micro-PDF417.