1, QR code:
Two-dimensional barcode Two-dimensional barcode is a black-and-white figure distributed on a plane (two-dimensional direction) according to certain rules, which is used to record data symbol information.
In coding, the concepts of "0" and "1" bit streams, which constitute the internal logic foundation of the computer, are skillfully used, and several geometric shapes corresponding to binary are used to represent the numerical information of characters, which can be automatically read by image input equipment or photoelectric scanning equipment to realize automatic information processing.
It has some characteristics of bar code technology: each coding system has its own specific character set; Each character occupies a certain width; It has certain verification function. At the same time, it also has the function of automatically identifying different line information and processing graphics rotation change points.
2065438+On August 3, 2006, the Payment and Clearing Association issued the Code for Barcode Payment Business (Draft for Comment) to payment institutions, which clearly pointed out the security standards that payment institutions need to follow when carrying out barcode business. This is the first time that the central bank officially recognized the status of QR code payment after 20 14 stopped QR code payment.
2. The basic characteristics of QR code:
(1) high-density coding, large information capacity: it can accommodate up to 1850 capital letters or 27 10 numbers or108 bytes, or more than 500 Chinese characters, which is several times higher than ordinary bar codes.
(2) Wide coding range: Barcodes can encode digitized information, such as pictures, sounds, characters, signatures, fingerprints, etc. , and represented by bar code; Can represent multiple languages; Can represent image data.
(3) Powerful fault-tolerant and error-correcting function: This enables the QR code to be read correctly when it is partially damaged due to perforation, fouling and other reasons, and the information can still be recovered when the damaged area reaches 50%.
(4) High decoding reliability: far lower than the decoding error rate of two millionths of ordinary bar codes, and the error rate does not exceed one millionth.
(5) Encryption measures can be introduced: good confidentiality and strong anti-counterfeiting.
(6) Low cost, easy manufacture and durability.
(7) The shape and size ratio of bar code symbols are variable.
(8) Two-dimensional bar codes can be read by laser or CCD reader.