What is a QR code, and how to use it?
On the labels of most products can be found motley black and white squares. “Some kind of another abstruse labeling” - many will say, not paying attention to it. But in fact, everything is much easier and more useful. This picture is called a QR code. What is a QR code, and how to use it, is described in this article.
What is a QR code?
A QR code was introduced in 1994 in Japan to account for goods. Innovation turned out to be more than a successful project and quickly went beyond the borders of the country, starting to be used in other areas where it could be useful. Still, what is a QR code from a technical point of view?
The picture is a block of encrypted text information. It is a two-dimensional implementation of a barcode, but unlike it, it can hold several orders of magnitude more information. In total there are 40 versions of the QR code, each of which differs by the dimension of the matrix - from 21 to 177 modules of width across the side, plus 4 modules of width of a free field around the image, for increased clarity of display on any background.
In addition to the usual full-length, you can meet the micro QR-code.From the traditional pattern differs only in dimension. It can contain 11, 13, 15 or 17 modules of width, plus 2 modules of a white field around the code. The maximum number of encrypted digits is no more than 35. You can create a QR code of this type using ordinary generators. There are no fundamental differences in encryption or reading.
Advantages over other similar systems
The main advantages of a QR code over a conventional barcode:
- Increased maximum amount of stored information.
- Data type Ability to write letters and special characters.
- Simplified reading system and process speed.
- More practical size.
In theory, it is possible to create code not only for textual information, but also for any other bit sequence, for example, pictures. Due to the high complexity and relatively small dimension of the array, this technology is not used.
The code encryption algorithm is rather complicated, but despite this, all the generators are able to create any QR code in seconds. What are algorithms and their principle of operation is a topic for a separate article; therefore, it is inappropriate to dwell on them now.Some programs are able to generate codes for specific needs. Plots of the finished image contain something similar to meta tags that indicate to the scanner that they belong to a particular class. So, modern smartphones can recognize in the QR code a phone number, an e-mail address, a link to the website and pages in social networks.
Since the size of the coded information is still limited, you can find chains of QR codes in which each subsequent one contains information that complements the previous one. It should be noted that the use of such schemes is extremely irrational, since placing one link inside a QR code for a resource with all the necessary information is a more practical solution.
Recognition and generation systems, structure
In order to scan a QR code, there is a huge number of programs for various devices and platforms. Practically all of them are free and provided free of charge. Algorithms of reading and generation have long been known, so any site or program can produce the correct result.
In theory, a device with any camera is able to recognize graphic code, text information, a picture and the like. It is only important that you have the necessary software.In the process of reading, search patterns are a very important element of the QR code. These are large black squares in the corners and areas around them. They work as guides and help the QR code scanner not to get confused among the variety of points, and also to determine the position of the code in the visible area of the scanner.
Everyone is able to generate their QR-code, saving any information in it. These can be links, phone number, short story, some instruction, etc. Fortunately, finding a QR code generator is also not a problem. These are usually the same resources that can scan it. To create your own code, you only need to provide the program with the text that should be encrypted.
Different levels of error correction make it possible to carry out manipulations with an already prepared image with the aim of, for example, styling it for specific needs. You can change the ready QR code in color or add a logo directly to the center, and it will still remain working. This will be useful if you intend to add such a "high-tech image", for example, on the cover of your site.
QR code help in sales
This recognition system entered active use relatively recently, but has proved to be quite effective for many purposes, including for use in sales. QR codes can be seen on almost all electronic products. Usually, they are encrypted with a link to the manufacturer’s website or a specific section with documentation about the product.
In technically developed countries, QR code is actively used for:
- Making instant purchases in large retail chains.
- Purchasing tickets.
- Pay bills in restaurants / cafes / hotels and other establishments.
- Contactless withdrawals at ATMs.
The risks in carrying out such operations are no more than the transfer of personal data in public networks, which means that systems that include a QR code can be considered well protected.
The technology of coding information on the principle of QR is useful not only in banking, but also in the social sphere. The use of information tablets with a QR code instead of a date and a brief description under popular monuments is a common thing. It is enough just to read the QR code with the link inside and get complete information about the object.Such a system is successfully used in museums, galleries, on popular tourist routes.
A QR code often appears in important documents, as it can accommodate all the necessary information or links to electronic signatures or personal identifiers in a few lines. On checks with the help of this technology often spread information about ongoing promotions, bonuses and personal discounts. Authentication processes and confirmation of actions are much easier to perform by simply scanning the code.
According to statistics, more than half of the population of the planet still do not use smartphones, which means that they are unable to decipher it on their own. Also, not all firmwares contain a built-in scanner, and without installing third-party software, they are not able to make out what a QR code is and what a normal picture is.
Unlike links or conventional barcodes, the QR code is not duplicated in a manner understandable to a person. It is impossible to remember or decrypt the encoded information in the absence of special equipment.