Posted in Interesting, Open Source, Softwares

Bar Code and QR Code

We see their usage on a day-to-day basis not only in air- conditioned retail stores but also with non-air-conditioned street vendors and hawkers. Yeah! I am talking about how bar code and QR code have digitized our societies, however large scale or small scale the business is. It doesn’t matter at all!

Bar code and QR code in general are digital form of information stored on a label of a product or services which provides the ease of tracking products in an inventory and payment of transactions. These are of great help as they minimize the process of typing to retrieve information.

Bar Code

Bar code visually appears as a combination of zebra stripped, multiple alternate black and white vertical lines which is readable by a machine. It follows a one-dimensional and two-dimensional pattern. The information of a bar code is stored in a simple numeric format with number ranging from 0 to 9, which can be retrieved when scanned by a bar code reader. In a store there are different product items. Each product has a bar code on in it. With this bar code information, the storekeeper can easily check how much stock is available. If an item is sold out, the scanner scans it and the item is deducted from stack and is added to the customer’s bill.

Bar code readers read the encoded information of bar code as input and decoding circuitry present outputs the information to the computer.

Bar code come in two varieties namely linear bar code, matrix(2D) bar code.

You might as well ask, what if the bar code sticker gets cut or blurred out. Yes, quite possible. The information of some part of the code might be lost and as the error correction mechanism is not good in case of bar code it may be difficult to recover the missing information. Additionally, the information that can be stored by bar code is limited when compared to QR code.

QR Code

QR abbreviated as Quick Response code is a pattern of black and white dots bounded on a square boundary. It follows a two-dimensional pattern. QR code can be read by imaging device typically a camera of smartphone and this process is called mobile tagging. The QR code typically detects three distinctive squares at the corners of the QR code image, using a smaller square near the fourth corner to normalize the image for size, orientation, and angle of viewing. The small dots throughout the QR code are then converted to binary numbers and validated with an error-correcting algorithm. This error correction mechanism gives QR code an advantage over barcode as information can be retrieved to some extent even if its spoiled or damaged.

QR codes have varieties namely Micro QR code, Secure QR code, Frame QR code.

QR code can be used to share information like business card, URL, social media profile etc which is also of benefit for lot of commercial markets for campaigning. With QR code one can track as to how many users have scanned your QR code. One disadvantage  a QR code can have is if you happen to scan a malicious QR code then a malicious ware might get into your phone which might hack your data or manipulate apps because we as a human won’t be aware if a correct QR code is being scanned or not.

In the near future, as a next level of evolution we will have 3D QR code. The height factor will give an advantage to store a little more information.