Why does a new species of applets look so much like chrysanthemums? Why does wechat launch small program code? What is the difference between it and ordinary TWO-DIMENSIONAL code?

For a long time, when people scan a QR code, many times they may not know what they are getting. The qr code may be behind the public account, payment page, may also be to add friends, product introduction or even wechat links.

The emergence of small program code, so that users before scanning code, there is a clear expectation, know that they are swept out of the small program.

Small program code in the style of more recognizable and visual impact, compared with the original TWO-DIMENSIONAL code, small program main brand LOGO is more obvious, can help developers better promote their small program. For wechat, the overall brand image of small program is clearer.

In the initial thinking of the visual design of the small program code, the principle of “more recognizable, clear user scan code expectations”, and “highlight the small program theme brand LOGO” to think, in addition, to ensure that the information carrying capacity and fault tolerance rate of the new small program code to meet the requirements.

Therefore, how to meet these several conditions at the same time, very elegant designer’s imagination.

The design of applets goes through three stages:

1, small program code design sketch:

The small program code at this time can be seen as the prototype of the final product.

2. Annotation map of visual finalization:

This drawing is a detailed description of the design.

3. The final choice of 36 radiation and its extended 72 radiation style.

(small program code)

In addition, the small program is independently developed on wechat, which has better security.


What’s the secret behind the scan?

Sweep code we use much, then why such an ugly black and white square two-dimensional code can sweep out all kinds of things?

Before the popularity of qr codes, people saw more one-dimensional codes, that is, bar codes. Bar code can only express information in the horizontal direction, can only store numeric and alphabetic information, store little information, application is very limited.



(Bar code structure)

Two-dimensional code is a more advanced bar code format than one-dimensional code, it can store information in both horizontal and vertical directions, storage information is large, so the application of two-dimensional code is much wider.

There are many kinds of two-dimensional Code, now we common two-dimensional Code is more accurate called QR Code, QR Code was invented by Japan DW company in 1994, very common in Japan, South Korea.

Qr code is similar to the answer sheet we used to fill in the exam. It is also marked with squares, so that the machine can quickly identify the right and wrong answers.

(Do you recall anything?)

Unlike the Answer sheet, the qr code is hidden behind the binary code, the black and white squares used to store binary information. Qr code with “black block” means “1”, with “white block” means “0”, the whole QR code of black and white square arrangement formed “1010110…” Such binary code to store numbers, text, links, images and other information.

The “back” mark on the three corners of the two-dimensional code square is the key positioning graph, or position detection graph, used to identify the two-dimensional code. So when scanning two-dimensional code, whether positive, oblique or even backward sweep can smoothly sweep out, is the credit of these positioning graphics.

(Qr code information)

At the same time, many people found that the QR code, even if part of the scratch or damage, can still be scanned normally. This is because two-dimensional code corrects errors through information redundancy, mainly by the “error correction code word” area to assume the role of data redundancy.

The amount of information a TWO-DIMENSIONAL code can carry is fixed, and the less information it contains, the greater the redundancy. The fault tolerance rate of two-dimensional code is generally about 7%~30%. If the two-dimensional code contains less information, the error correction code word area can be recognized by covering up to 30%.


The answer to this article comes fromWeChat team