A QR (quick response) code is a two-dimensional barcode that consists of a matrix of black and white squares. It can store various types of information – text, links, contacts – which is read by a smartphone or tablet camera. Let’s look at how the QR code recognition process works. By using the best QR code generator, businesses can easily create customized QR codes for their needs.
Contents
How a QR Code is Structured
The structural arrangement of a QR code is markedly different from traditional barcodes, offering a higher level of information load and functionality. The basis of a QR code consists of functional sections, each performing its own specific role. The corners of a QR code contain variable positional markers of a certain size, which allow you to determine the version and dimensions of the matrix, which is important for correctly reading the information. Along the sides of the QR code, there is a thin line that facilitates precise focusing during scanning, which speeds up the recognition process. The main area of the QR code is the data section, where numbers, letters and symbols are encoded as a black-and-white pattern representing a two-dimensional matrix code.
QR codes come in 40 sizes, ranging from 21×21 to 177×177 dots. The larger the matrix size, the more information can be encoded in the QR code. For example, the capacity of a QR code increases with increasing size, allowing efficient encoding of different data types depending on specific usage needs. This flexibility in sizes makes QR codes extremely adaptable for various applications, from advertising and marketing to healthcare and education.
Scanning a QR Code with a Smartphone Camera
To recognize a QR code, the camera scans the matrix based on the pattern of alternating black and white squares. The key role here is played by the focus – the clearer the code is captured, the easier it is to read. In addition to focusing, lighting and tilt angle also have an effect. Uneven lighting can cause glare and shadows that impede recognition. It is optimal to direct the camera perpendicular to the plane of the code.
- The QR code is captured by the camera on a smartphone or scanner.
- The QR code consists of black and white square modules arranged in a grid pattern.
- The scanner software analyzes the QR code by reading the pixel values in the image.
- It interprets the pixel values as either black or white squares.
- Based on the arrangement of the squares, the software decodes the encoded data.
- QR codes have finder patterns at the corners and alignment patterns to assist with scanning.
- The finder patterns help the scanner locate and orient the QR code.
- The alignment patterns enable scanning the code from any angle or orientation.
- Once the position of the QR code is determined, the encoding region is analyzed.
- The encoding region contains the actual data encoded in the QR code.
- The data is extracted using Reed-Solomon error correction and other coding techniques.
- The extracted data may contain text, URLs, contact info, etc.
- The scanned QR code data is passed to the application for further processing.
- The app interprets the decoded data and performs the appropriate action.
Decoding and Interpreting Data
After capturing the visual image of the QR code, special algorithms come into play that decode and correct any possible errors or noise.
During decoding, the information encoded in the code – numbers, letters, symbols – is extracted from the matrix. Then, based on the service data, this information is converted into text, a link, or another format.
Displaying the Result to the User
After successful processing, the information from the QR code becomes available to the user in a convenient format. This may be:
- a web page that is instantly accessed;
- contacts, events, reminders added to the phone;
- a text message displayed on the screen, etc.
Thus, in a matter of seconds, the QR code transfers the useful information contained in it to the mobile device.
Advantages of QR Codes
A QR code is a convenient and fast way to transfer various kinds of information. It provides:
- high data encoding density;
- reliability and damage resistance;
- ease and speed of scanning by a smartphone camera;
- automatic decoding and error correction.
In addition to the adaptability and convenience of the technology itself, it is also worth noting that its accessibility is ensured by dozens of free online QR code generators. One such example is ME-QR, which allows customization and tracking analytics of generated codes.
Thanks to this, QR codes have become widely used in advertising, marketing, logistics, and other areas as a convenient digital data format. They can be instantly scanned from a smartphone to access the encoded information.


