Quick Response, or QR, codes are two-dimensional codes that were first introduced to the public through the automotive industry. These matrix barcodes have become increasingly popular over time and has spread across various industries outside of the automotive field. This is simply because these codes have a large storage capacity and can be read easier when speaking in terms of comparison against other codes. When looking at the code, you can recognize it because of the white background and a pattern of black modules that are shaped like a square.
Data Encoding Types
When encoding, there are various forms of data that can be used, some of which include Kanji symbols, alphanumeric and binary data. Kanji symbols are a collection of data used in the writing system of modern Japan. This particular type of data uses logographic Chinese symbols, Indo Arabic numerals, katakana, hiragana and sometimes the Latin alphabet. Alphanumeric data is simply a combination of numeric and alphabetic characters while the binary data system consists of a number system that only uses 0 and 1.
When storing data inside the QR code, you must first determine the type of character set you will use. This is important since each set of characters have varying sizes. It also depends on the error correction level and the version of the quick response code you decide to use. For instance, if you have an error capacity level of L and version 40, the maximum number of characters you can use for numeric values is 7,089 characters; for alphanumeric, the maximum is 4,296 character; for Kanji, the maximum is 1,817; and for Binary, the maximum is 1,817 characters.
Encryption and Error Correction
When speaking in terms of QR code encryption, there are a few implementations that exist. Even though it is rare that you will come across a code that is encrypted, applications are available that allow you encrypt and decrypt codes with use of the DES algorithm. An example of one purpose you will find encrypted codes used for is through passport visas, especially with Japanese immigration. There are smart-phone applications available that also allow you to decrypt and manage encryptions of this code.
There are four different levels of error correction that exist. If the error correction level is particularly high, there is less storage space to work with for using the code. The precise number of corrections that can be made are dependent on the error locations and the actual size of the symbol. Codewords have a length of eight bits, which is vital to know when determining the error correction level to use. The lowest level is L, which corrects 7 percent of errors; level M corrects 15 percent; level Q corrects 25 percent and level H corrects 30 percent.
Variations and Usage
If you do not have much data to store, consider using a Micro QR code instead of the Standard QR code for your needs. This smaller variation allows you to store as many as 35 numeric characters. Outside of the automotive industry, this code is also used in commercial tracking, in-store product labeling, product marketing, transport and entertainment ticketing. In recent times, you also have cell phone applications that allow you pay for your products with a code on your phone that contains information on your method of payment.
QR Code Risks
Although there are many benefits of using this type of coding, there are also risks involved. When using these types of codes, be careful of malicious codes. These malicious codes can put your privacy at risk, including all of the information on the computer. Risks include coming in contact with dangerous websites and sensitive data. When you come in contact with these types of risks, you will not be able to notice what is happening in the background most of the time.