The document discusses QR codes, including: - QR codes were created in 1994 by Denso Wave to track vehicle parts and became widely used in Japan in 2002 with mobile phones. - QR codes can store various data types and are read by smartphones. They consist of black square modules arranged in a pattern on a white background. - The error correction capability allows QR codes to be read even if dirty or damaged. It employs Reed-Solomon codes to generate error correction codewords. - QR code versions range from 1 to 40, with higher versions having larger matrix sizes and storage capacity. Structure includes data, error correction codewords, and format/version information.

1. QR CODES
DEPARTMENT OF ELECTRONICS AND TELECOMMUNICATION ENGINEERING
A SEMINAR ON
INDIRA GANDHI INSTITUTE OF TECHNOLOGY
SARANG, DHENKANAL, ODISHA
SUBMITTED BY-
NAME-PRANAB SRITAM SAHU
REGD.NO.- 2001105381
ROLL NO.- 398030
SCAN ME

2. CONTENT
1. INTRODUCTION
2. EVOLUTION
3. VESIONS OF QR CODE
4. STRUCTURE OF QR CODE
5. QR CODE ERROR CORRECTION
6. ENCODING
7. DECODING
8. TYPES OF QR CODES
9. REFERENCES

3. Introduction
Contents Here
• A QR code is a type of matrix bar code or
two-dimensional code that can store data
information and designed to be read by
smartphones.
• QR stands for “Quick Response”
indicating that the code contents should
be decoded very quickly at high speed.
• The code consists of black modules
arranged in a square pattern on a white
background. The information encoded
may be text, a URL and other data. [1,2]
01

4. Evolution
1994
1960
s
2002
QR Codes are created
by the Toyota
subsidiary Denso
Wave in 1994, and
was initially used for
tracking inventory in
vehicle parts
manufacturing.[1,2]
Traditional
barcodes and the
POS system, where
a cash register
displays the price
of an item after
the barcode was
scanned by an
optical sensor.[3]
In 2002, mobile
phones in Japan
were equipped with
a QR code-reading
prompting
widespread public
usage, so people
could access
websites and obtain
a coupon by

5. Versions Of QR Code
"Module configuration" refers to the number of modules
contained in a symbol, commencing with Version 1 (21 × 21
modules) up to Version 40 (177 × 177 modules) [4].
Figure 2:- Module configuration of the basic QR
codes.
The symbol versions of the QR Code range from Version 1
to Version 40. Each version has a different module
configuration or number of modules. (The module refers to the
black and white dots that make up QR Code).

6. Structure Of QR Code
Fig.3- Structure Of a QR Code[5]

7. VERSION MODULE
S
ECC
LEVEL
APPROX.
AMOUNT
OF
CORRECTIO
N
DATA
BITS
NUMERI
C
ALPHA
NUMERIC
BINARY KANJI
40 177*177 L 7% 23648 7089 4296 2953 1817
M 15% 18672 5596 3391 2331 1435
Q 25% 13328 3993 2420 1663 1024
H 30% 10208 3057 1852 1273 784
QR Code Error Correction
 QR Code employs error correction to generate a series of error
correction codewords which are added to the data codeword
sequence which enable symbol to be read even if it is dirty or
damaged.
 The QR code achieves powerful error- correction capability by using
Reed-Solomon codes, a widely used mathematical error-correction
TABLE 1: ECC LEVEL & DATA CAPACITY OF QR CODE VERSION 40

8.  Data analysis:- to determine whether text can
be encoded in numeric, alphanumeric, byte, or
Kanji mode, and then select the most optimal
mode for the text.
 Data encoding:- it creates a string of bits that
is a codeword of 8 bits long.
 Error Correction Coding:- by using reed
Solomon process error correction codeword is
generated from the 8 bit codeword.
 Structure Final Message:- Data and error
Encoding
Fig.4- QR Code Encoding

9. 9
 Module Placement in Matrix:-The bits
are placed in QR code matrix & these
arranged in a specific way.
 Data Masking: The QR code
specifically defines eight mask
patterns, each altering the QR code
according to a particular pattern.
 Format and Version Information:
Pixels are added in particular areas .
The format pixels identify the error
correction level and mask pattern
Fig.4- QR Code Encoding
10/1/2023

10.  Recognizing Modules: Recognize dark and light
modules as an array of “1" and “0" .
• Extract Format Information: It identifies the
masking pattern and ECC level used in the QR
Code.
• Determine Version Information: It determines the
Specific version of QR Code which is used.
• Release Masking: XOR the encoding region bit
pattern with the Mask Pattern.[5,6]
Decoding
Fig.5- QR Code decoding

11. 11
• Restore Data and Error Correction
Codewords: it is done by reading the
symbol .
• Error Detection and Correction: it identifies
the errors and if found is corrected.
• Decode Data Codewords: Divide the data
codewords into segments according to the
Mode Indicators and Character Count
Indicators. And finally, decode the data
Fig.5- QR Code decoding
10/1/2023

12. Types Of QR Codes
Fig.7-
Different
types
of
QR
Codes

13. 1.Dong-Hee Shin, Jaemin Jung. Byeng-Hee Chang "The psychology behind QR
Codes: User experience perspective"Science Direct.
2.Phaisarn Sutheebanjard, Wichian: Premchaiswadi, "QR CodeGenerator", IEEE
2010 8th International Conference on ICT and Knowledge Engineering pp 89-92.
3. https://www.logmore.com/post/evolution-of-the-qr-code-history
4.QR Code Tutorial, http://www.thonky.com/qr-code-tutorial
5. ISO/IEC 18004:2000. "Information technology-Automatic identification and data
capture techniques Bar Code symbology- QR Code", 2000.
6.https://www.researchgate.net/publication/318125149_An_Introduction_to_QR_
Code_Technology
References

14. THANK YOU
For Your Patience Hearing
SCAN ME