QR codes consist of black modules arranged in a square grid that can be read by a camera. They can store text, URLs, contact info, and other data. First created in 1994, QR codes use patterns and error correction to maximize data storage while allowing parts of the code to be damaged. They are widely used to link the physical world to digital information by encoding URLs or text that smartphones can read.

1. QR Codes
PRESENTED BY :
SIMRAN GUPTA
GUIDED BY:
MR. DISHANT AGRAWAL
MS. SONIKA GUPTA

2. A QR code consists of black modules arranged in a
square grid on a white background, which can be
readable by an imaging device.
A QR Code is a two-dimensional barcode that is
readable by smart-phones or other handheld devices.
WHAT IS A QR CODE?

3. BAR CODE VS QR CODE

4. HISTORY
 Created by Toyota subsidiary Denso-Wave in
1994.
 First used for tracking parts during vehicle
manufacture.

5. STRUCTURE OF QR CODE
VERSION 2
1. Finder Pattern
2. Separators
3. Timing Pattern
4. Alignment Patterns
5. Format Information
6. Data
7. Error Correction
8. Remainder Bits

6. 1. Finder Patterns : It enable the decoder software
to recognize the QR Code and determine the correct
orientation.
2. Separators : It improve the recognizability of the
Finder Patters as they separate them from the actual
data.
3. Timing Pattern : Alternating black and white
modules in the Timing Pattern enable the decoder
software to determine the width of a single module.
4. Alignment Patterns: It support the decoder
software in compensating for moderate image
distortions.

7. 5. Format Information: It consists of 15 bits next to
the separators and stores information about the error
correction level of the QR Code and the chosen masking
pattern.
6. Data : Data (bit stream) stored in 8 bit parts.
7. Error Correction : error correction codes are stored
in 8 bit long code words.
8. Remainder Bits : It consists of empty bits if data
and error correction bits can not be divided into 8 bit
code words without remainder.

8. How to Create QR Codes

9. How to Read a QR Code
• Mobile device must have
a camera.
• Start the QR reader
application.
• Point the camera at the
code ( orient code within
designated area ).

10. Text

11. SOME QR SCAN RESULTS

12. URL of my website

13. Phone Number

14. Email Address

15. V-Card

16. Uses and Applications
QR Codes may be used to display:
 Text
 URL(most common)
 Contact information
 Email
 V-Card
 Convenience-oriented applications ,etc.

17. Storage

18. Error Correction
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.
Codewords are 8 bits long and use the
Reed–Solomon error correction
algorithm with four error correction
levels. The higher the error correction
level, the lesser storage capacity.

19. Encoding
• The format information records two things:
-the error correction level
-the mask pattern used for the symbol
• Masking is used to break up patterns in the data area that
might confuse a scanner, such as large blank areas or
misleading features that look like the locator marks. The
mask patterns are defined on a grid that is repeated as
necessary to cover the whole symbol. Modules
corresponding to the dark areas of the mask are inverted.

20. •The format information is protected from errors with a
BCH code.
•Two complete copies
are included in each
QR symbol. The
message dataset is
placed from right to
left in a zigzag
pattern, as shown
below.
Fig: Meaning of format information

21. Advantages of QR code
• QR Codes are beneficial for both customers and
businesses. For example, a business saves money and
advertising costs by distributing a QR code to their
website or URL. A customer can scan this QR code
and this allows them to store the information for
future reference.
• Huge storage capacity.

22. Disadvantages of QR code
• Lack of familiarity of the QR code among people.
• Dependability on a mobile device or smart-phone.

23. Examples

24. Object hyperlinking
Object hyperlinking aims to extend the Internet to
the real world by attaching tags with URLs to tangible
objects or locations.
These tags can then be read by a wireless mobile
device and information about objects and locations
retrieved and displayed.

25. “Finally, the greatest importance of QR codes
could lie not in their specific use, which may be
superseded by newer codes and interpreters, but
in the opportunities they offer for moving away
from keyboards as input devices in learning
environments.”
Conclusion

26. References