1. Barcode and QR code
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Yuan Qu, Xuansheng Lu

2. Introduction to barcode Introduction to QR code
Content
Introduction to barcode
What is a barcode?
How barcode works?
The application of barcode in daily life.
Introduction to QR code
What is a QR code?
How to form a QR code from existing data？
How can QR code be applied to daily use?

3. Introduction to barcode
What is a barcode?
How barcode works？
The Application of barcode in daily life.

4. Introduction to barcode
What is a barcode?
How barcode works？
The Application of barcode in daily life.

5. What is a barcode? A machine readable representation of information
Consisting of a group of printed and variously patterned bars and spaces
An automatic identification technology
A patent for “Classifying Apparatus And Method” was filed by Woodland and Sliver in 1949 and it was issued as US Patent in 1952.
The first product with a bar code was scanned at a check-out counter in 1974.

6. Why use barcode?
Speed
Saving time that market clerks type in price when customers purchasing several items.
Cost Saving
Saving money to ask employees tracking merchandise.
Saving time to track more goods.
Error Prevention
Manual tracking leads to many human errors.
Barcodes can reduce the error rate to a low percentage, about one error for every three million entries.

7. Types of barcode
The type of barcode to use for a particular situation depends upon:
The use.
The data encoded in the barcode.
How the barcode will be printed.

8. UPC
Country: the US, the UK, Australia, New Zealand and other countries.
Industry: Retail
Variations: UPC-A, UPC-E
Encode: Numbers 0-9

9. EAN Country: mainly in Europe. Industry: Retail
Variations: EAN-13, EAN-8, JAN-13, ISBN, ISSN
Encode: Numbers 0-9

10. Code39 Country: Worldwide Industry: Automotive and Defense
Encode: Numbers 0-9, capital letters A-Z, symbols -.$/+% and space

11. Code128
Country: Worldwide
Industry: Supply Chain
Encode: ASCII

12. Introduction to barcode
What is a barcode?
How barcode works？
The Application of barcode in daily life.

13. The structure of barcode

14. The structure of barcode

15. The structure of UPC/EAN
3*( )+( )=116
Check digit = 10-6=4

16. The structure of UPC/EAN
Every character is encoded using 11 numbers
Left guard bar: 101
Center bar: 01010
Right guard bar: 101

17. Left hand encoding: OEOEOE
How UPC/EAN works
Encoding “ ”
Check digit is 9
Left hand encoding: OEOEOE
The first digit is 7

18. How UPC/EAN works Find encoding methods in the form.
Connect all together, we get
Left hand encoding: OEOEOE

19. The structure of code128
A start character has three types; "CODE-A", "CODE-B" and "CODE-C". The type of start character determines the character composition of subsequent characters.
"Modulus 103" is used as a check digit.
Every character is encoded using 11 numbers except for the stopcode, which is encoded in 13 numbers.

20. CHECKSUM = ( 35+51*2+37*3+19*4+23*5+16*6 ) mod 103 = 20 = 11001001110
How code128 works
Encoding “CSE370”
START A =
C = 35 =
S = 51 =
E = 37 =
3 = 19 =
7 = 23 =
0 = 16 =
STOPCODE =
CHECKSUM = ( 35+51*2+37*3+19*4+23*5+16*6 ) mod 103 = 20 =

21. Introduction to barcode
What is a barcode?
How barcode works？
The Application of barcode in daily life.

22. Application of UPC/EAN

23. Application of code39
AIAG(Automotive Industry Action Group)

24. Introduction to QR code
What is a QR code?
How to form a QR code from existing data？
How can a QR code be applied to daily use?

25. Introduction to QR code
What is a QR code?
How to form a QR code from existing data？
How can QR code be applied to daily use?

26. What is a QR code? Similar to barcode
Support more amounts and types of data
A kind of code restoring data
Created by Denso in Sept 1994
Just got popular in recent years.
Due to development of smart
phones and online platforms

27. More data contained in codes
Why QR code?
More chars supported
Numerical chars
1~9
Alphabets
a~z, A~Z
UTF-8 codes (decoder needs ECI)
Most chars are supported
Convenience
No direction requirements
High recognition speed
Good error correction ability
Easy to create when needed
More data contained in codes
Changeable size of the code
From 21*21 to 177*177
Smallest version supports 41 numbers at most
Largest version supports 1817 UTF-8 chars at most

28. Detailed Structure of QR code

29. Detailed Structure of QR code

30. Version of QR codes …… V1-L V2-L V3-L V40-H Version Range Numeric mode
Alphanumeric mode
Kanji mode
1~9
10 bits
9 bits
8 bits
10~26
12 bits
11 bits
27~40
14 bits
13 bits
Bits taken by a char indicator

31. Coding Mode and Error Correction Level
Original data
Mode
Mode Indicator
Max char numbers
Numeric
0001
7089
Hello
Alphanumeric
0010
4296
Γεια σου
Byte (ISO )
0100
2953
こんにちは
Kanji
1000
1817 你好
ECI
0111
~800
Error Correction Level
Error Correction Capability L
About 7% M
About 15% Q
About 25% H
About 30%
Version, EC level determines how many codewords are needed!

32. Introduction to QR code
What is a QR code?
How to form a QR code from existing data？
How can a QR code be applied to daily use?

33. Overview Decide Version & Error Correction Level & Coding Mode
Original Data Encoding and Partition
Generate Error Correction Code
Codewords Placement
Masking
Format and Version Information Placement

34. Overview Decide Version & Error Correction Level & Coding Mode
Original Data Encoding and Partition
Generate Error Correction Code
Codewords Placement
Masking
Format and Version Information Placement

35. Version, EC level determination
Version, EC level, Coding mode
Bit length for a char
Number of groups
Number of blocks in a group
Number of codewords in a block
EC codewords per block
&
EC Gen Poly
Alignment pattern numbers
Version and EC Level
Total Number of Data Codewords
EC Codewords Per Block
1-L 19 7
1-M 16 10
1-Q 13
1-H 9 17
2-L 34
2-M 28
2-Q 22
2-H

36. Overview Decide Version & Error Correction Level & Coding Mode
Original Data Encoding and Partition
Generate Error Correction Code
Codewords Placement
Masking
Format and Version Information Placement

37. Encoding Original Data
Add a terminator
Add 0s to satisfy digit number mod 8 =0
Determine required number of bits for code
Padding
Select a suitable mode to encode.
Check table for the block numbers
To satisfy bit requirement for the indicator.
Required block numbers *8
To meet the required bits for code

38. Encoding Original Data
134
554 3
101 …
Every 3 numbers a group
Numeric mode: 10 bits
Add mode code (0001)
&
Add the length of original data (7)
Terminator up to 4 bits
&
Add 0s till length mod 8 = 0
Add until it arrives 104(13*8) bits.

39. Overview Decide Version & Error Correction Level & Coding Mode
Original Data Encoding and Partition
Generate Error Correction Code
Codewords Placement
Masking
Format and Version Information Placement

40. Error Correction Coding
Original Data Codewords
Message Polynomial
Repeat for N times
Divided by
Check table
Version, Error Correction Level
Generator Polynomial =
Error Correction Code
RS code Polynomial
Original Data Codewords:
N: codeword numbers for a block

41. Overview Decide Version & Error Correction Level & Coding Mode
Original Data Encoding and Partition
Generate Error Correction Code
Codewords Placement
Masking
Format and Version Information Placement

42. Module Placement in Matrix
Place Finder Patterns
Place Alignment Patterns &
Add timing patterns
Reserve Areas &
Add Dark Module
Place Data Bits

43. Module Placement in Matrix
Two cols per line
Notes
1.Ignore reserved positions
2.Skip the alignment patterns

44. Overview Decide Version & Error Correction Level & Coding Mode
Original Data Encoding and Partition
Generate Error Correction Code
Codewords Placement
Masking
Format and Version Information Placement

45. Masking 𝐷 𝑖𝑗 = 𝐷 𝑖𝑗 XOR 𝑀 𝑖𝑗
Calculate the penalty respectively for 8 Mask Patterns
Choose the one with least penalty, record the pattern reference

46. Masking
Masking mainly for devices better recognize the QR code

47. Overview Decide Version & Error Correction Level & Coding Mode
Original Data Encoding and Partition
Generate Error Correction Code
Codewords Placement
Masking
Format and Version Information Placement

48. Format and Version Information
Format info
1~2:Error Correction Level bits
3~5: Mask Pattern Reference bits
6~15: Error correction bits
Version Info
V1~V6:0
V7~V40: corresponding binary number, totally 6 bits
7~18: Error correction bits

49. Included in format info
Decoding the QR codes
Included in format info
Codeword’s position is determined for certain version and correction level

50. Decoding the QR codes Outer side with white paddings for recognition
Alignment Patterns are for helping determine direction of the QR code

51. Introduction to QR code
What is a QR code?
How to form a QR code from existing data？
How can a QR code be applied to daily use?

52. QR Code’s Application in Daily Life
Detailed Product Information/Instruction
Providing apps for the products
Products
Personal Information
Personal
Social network friend adding
Online payment
Other Uses

53. How are these applications realized?
URL
App download link
Homepage
API Link
Account Number
Deduction
Further operation

54. Wechat QR code Applications
Website login QR code
Personal QR code
Receipt QR
code
wxp://f2f0DkCOPXre

55. Outlook of QR codes Security Preservation
Increasing user engagement in museum-like spaces/Teaching quality
Using QR codes to increase user engagement in museum- like spaces.
Further application in Share Systems
Improvement in smart phone’s camera
Security improvement in QR code uses
Distributed Secret Sharing Approach With Cheater Prevention Based on QR Code.

56. Assignments for you
Generate a QR code on a website, including a brief self introduction, try to include your age, nationality, major, gender etc.
Is there any way to restore your self introduction in a simpler QR code?
Try to add some hobby introduction to the previous introduction
Generating a new one is good, but you need to republish your QR code to others.
Is it possible to add or change your data without changing your QR code?

57. Types of QR Codes in Application
Contain determined data
If you need to do changes to original data, a new QR code needs to be generated
Static QR code
Contain a URL pointing to a website
The data are well organized on the website
The certain website can also redirect devices to a new website
Dynamic QR code
Dynamic Code
Static Code

58. References and Q&A QR code online generation:
chanism/
<Distributed Secret Sharing Approach With Cheater Prevention Based on QR Code.> IEEE Trans. Industrial Informatics-2016
<Using QR codes to increase user engagement in museum-like spaces.> Computers in Human Behavior
QR code online generation:
(static QR codes)
Note almost all the dynamic QR codes online generation requires you to register on certain websites.