Will the QR code be used up?

Two-dimensional code is also called two-dimensional bar code. The common two-dimensional code is QR Code, and the full name of QR is Quick Response. It is a very popular encoding method on mobile devices in recent years. It can store more than traditional Bar Code. The information can also represent more data types.

Two-dimensional bar code/two-dimensional bar code (2-dimensional bar code) uses a certain geometric figure to record data symbol information in a black and white pattern distributed on a plane (two-dimensional direction) according to a certain rule; ingenious in coding Utilize the concept of "0" and "1" bit stream that constitute the internal logic of the computer, and use several geometric shapes corresponding to the binary system to represent the text value information, which can be automatically read by image input equipment or photoelectric scanning equipment. Automatic information processing: It has some common features of barcode technology: each code system has its own specific character set; each character occupies a certain width; it has certain verification functions, etc. At the same time, it also has the function of automatically identifying different lines of information, and processing graphics rotation change points.

Will the QR code be used up?

It can be known from the principle of two-dimensional code recognition: a two-dimensional code is a graphic generated by the arrangement and combination of black and white blocks in a certain standard matrix, so after the matrix specification is determined, its permutation and combination must be limited in number.

At present, there are a total of 40 specifications of the QR code, called Version1-40, the minimum Version1 represents a 21*21 matrix, and the maximum Version40 is a 177*177 matrix. Take the 25*25 matrix (wei letter payment code adopts this specification) as an example, excluding positioning graphics, separators, etc., there are still 478 squares.

Each square has two forms of black and white, and 478 squares can be arranged and combined to form 2^478 QR codes, that is, 780437137578998057845399307448291576437149535666242787714789239906342934704941405030076525765872992789956732780351655723861993919822071326572544 QR codes.

Is this number very scary? When we run out of wei letter payment codes, it may take billions, billions, billions, billions...years, far beyond the age of the earth (about 4.55 billion years), so the QR code It can't be used up.