A two dimensional bar code which is widely used to encode & provide easy assess to information.

1. ‘QR’ code
Presented by:
ADITYA JHA
Section “A”
(BSC Hons Computing)
1

2. BAR CODE
What is a barcode?
A barcode is an optical machine readable representation
of data relating to the object to which is attached.
2

3. Quick Response Code
3
What is a QR code?
A two dimensional bar code which is widely used to
encode & provide easy assess to information.

4. QR Code
4
The QR code system was invented in 1994 by
Toyota’s subsidiary, Denso Wave.
Initially used to track vehicles & for tracking parts
during manufacturing.
Now its’s also used to easy share the link and
transfer information on smartphones.
The information on a QR code is typically some sort
of actionable text that directs the phone to take
some sort of action

5. How it works?
5
 It requires a QR scanner application which is to be installed in
smart phone or computer to decode the information in QR
code.
QR code generator Print or link User connects with smart
phone or computer

6. 6
 QR code are made up of black squares and white squares.
 Each of these squares is called a module.
 In every QR code, there are certain modules that must not
be covered or edited, else the code won’t scan.

7. Encryption
7
Error correction
Encrypted QR codes, which are not very common, have a few
implementations.
The QR App, manages encryption and decryption of QR codes
using the DES algorithm.
It has a function of an error correcting for miss reading that
white is black.
It use the Reed-Solomon error correction algorithm with
four error correction levels.
Capacity of a QRcode is determined by version, error
correcting level and encoding mode.

8. 8
Level L (Low) 7% of codewords can be restored.
Level M (Medium) 15% of codewords can be restored.
Level Q (Quartile) 25% of codewords can be restored.
Level H (High) 30% of codewords can be restored.

9. Decryption
9
 The three large square highlighted in red are the position
markers.
 These tell the scanner where the edges of the code are.

10. 10
The smaller red square is an alignment marker.
The red strips of altering black and white
modules are called timing patterns. They define
the positing of the rows and column.
The green sections determine the format. This
tells the scanner whether it’s a website, text
message, Chinese symbols, numbers, or any
combination of these.
The modules highlighted in blue represent the
version number.

11. Version of QR code
11

12. Scanning a QR code
12
The information is read by a mobile phone equipped
with a QR code reader, which works in conjunction with the
phone’s camera to decode the information.

13. Uses
13
 URL: A QR code can be used to encode the text of a URL, which
will be opened a web browser.
 Telephone Number: A QR code may also contain a phone
number. When a code is read the phone’s dialer will open with
the number filled in, and also the QR code can automatically
place the call by asking permission.
 SMS: A QR code may contain a number that is ready to receive a
text message. The QR code reader would promote the phone to
open the messing client, and would open a new message that
the user can compose and send.
 The QR code can store up to 4,296 alphanumeric or 7,089
numeric characters.

14. QR Code Readers Apps
14
QR Code Reader for Cell Phones:
 Kaywa
 Beetagg
QR Code Reader for Computers:
 NeoReader
 QuickMark

15. 15

16. Reference-
 http://en.wikipedia.org/wiki/QR_code
 http://whatis.techtarget.com/definition/QR-code-quick-responce-code
 http://www.qrstuff.com
16

17. 17