The barcode composed of multiple lines does not need to be connected to a database, and it can store a large amount of data. It can be used in: hospitals, driver's licenses, material management, and cargo transportation. When the barcode is damaged, the error correction can make the barcode decode PDF417 correctly. A product developed by Symbol Technology Corporation in 1990. It is a multi-line, continuous, variable-length, symbolic sign containing a large amount of data. Each barcode has 3-90 lines, and each line has a start part, data part, and end part. Its character set includes all 128 characters, and the maximum data content is 1850 characters.
A) Introduction to PDF417
The PDF417 code was invented by Dr. Yinjing Wang, a Chinese studying in the United States. PDF is an acronym for the three words of English Portable Data File, meaning "portable data file". Because each symbol character that makes up a barcode is composed of 4 bars and 4 spaces, if the narrowest bar or space that makes up a barcode is called a module, the total number of modules with 4 bars and 4 spaces mentioned above is one. It is set at 17, so it is called 417 code or PDF417 code.