The document provides a comprehensive overview of QR codes, highlighting their history, design, storage capacity, encoding process, and usage. It outlines the advantages and disadvantages of QR codes, emphasizing their versatility and effectiveness in linking mobile users to online content. Key technical details include error correction levels and different versions that affect the storage capacity and design characteristics of QR codes.

1. QR Code
Presented By
Ajay Verma
M.Tech CSE

2. What is QR Code
• Type of matrix barcode (or two-dimensional barcode)
• First designed for the automotive industry in Japan.
• It is a special type of matrix barcode that can encode
information like numbers, letters, and Kanji characters.
• Greater storage capacity compared to standard barcodes.

3. History
• 1952 Patent of first barcode device
• 1966 Begins commercial use; lack of standard
• 1970 UGPIC established to make industry standard
• 1973 UGPIC turns into UPC (today’s standard barcode)
• 1974 Barcodes implemented in a supermarket for the first
time
• 1988 Intermec Corporation creates the first 2D barcode
• 1994 Denso Wave creates the QR Code for manufacturing
vehicles
• 2010 QR Readers appear as apps for Smart Phones
• 2011 QR Codes become mainstream advertisements

4. Its uses
• URL
• vCard
• YouTube Video
• Facebook
• Twitter Follow
• Google Maps:
• Plain text:
• Email Address:
• Application URL:
• And much more…

5. QR Code Design
• Position Markers
• Format
• Version Number
• Alignment Marker

6. QR Codes Versions
• There are also different versions (currently up to 40).
• These are determined by a numeral in a chart, followed by a
error correction level. By following the two, the version number
is reached.
Version 1
(21×21) Version 3
(29×29).
Version 40 (177×177)

7. Storage capacity
The amount of data that can be stored in the QR code symbol
depends on the datatype (mode, or input character set), version (1,
…, 40, indicating the overall dimensions of the symbol), and error
correction level. The maximum storage capacities occur for 40-L
symbols (version 40, error correction level L)
Input mode Max. characters
Possible characters, default
encoding
Numeric only 7,089 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
Alphanumeric 4,296
0–9, A–Z (upper-case only),
space, $, %, *, +, -, ., /, :
Binary/byte 2,953 ISO 8859-1
Kanji/kana 1,817 Shift JIS X 0208
Maximum character storage capacity (40-L)
character refers to individual values of the input mode/datatype

8. Back

9. Error Correction
Still works!
•Use the Reed–Solomon error
correction algorithm with four
error correction levels.
•The higher the error correction
level, the less storage capacity.
•Due to error correction, it is
possible to create artistic QR
codes that still scan correctly

10. Encoding
• Encoding of “ HELLO WORLD ” string.
• Step 1: Choose the Error Correction Level
• Step 2: Determine the Smallest Version for the Data
• Step 3: Add the Mode Indicator
• Step 4: Add the Character Count Indicator
• Step 5: Encode Using the Selected Mode
• Step 6: Break Up into 8-bit Codewords and Add Pad Bytes if
Necessary:
• 00100000 01011011 00001011 01111000 11010001
01110010 11011100 01001101 01000011
01000000 11101100 00010001 11101100

11. • Now in error correction coding section, we use Reed-Solomon
error correction algorithm to get data codewords and their
corresponding error correction codewords.
• the data and error correction codewords were interleaved,
and the final string of bits was obtained.
• The next step is to put them in the QR code matrix.

12. • The finder patterns are the three
blocks in the corners of the QR code at
the top left, top right, and bottom left.
• The separators are areas of
whitespace beside the finder patterns.
• The alignment patterns are similar to
finder patterns, but smaller, and are
placed throughout the code. They are
used in versions 2 and larger, and their
positions depend on the QR code
version.
• The timing patterns are dotted lines
that connect the finder patterns.
• The dark module is a single black
module that is always placed beside
the bottom left finder pattern.
Overview of Function Patterns

13. Alignment Patterns

14. Place the Data Bits

15. Data Masking
• masking simply means to toggle the color of the module.
• Mask patterns must ONLY be applied to data modules and error
correction modules.

16. Format Information

17. Version Information
If the QR Code is version 7 or larger, you must include an 18-
bit version information string in the bottom left and top
right corners of the QR code.

18. Final Output
A 1-Q code of HELLO WORLD

19. Conclusion
Advantage:-
• The main advantage of a QR code is its versatility
• Easy way to send mobile users to online content
• They appeal to mobile users' curiosity
• QR codes can be cost effective
Disadvantage:-
• Users need to download a QR code reader
• Lack of awareness
• Security

20. References
[1]. QR Code https://en.wikipedia.org/wiki/QR_code accessed on
21/10/2017 at 10:30 AM.
[2]. Error Correction Feature
http://www.qrcode.com/en/about/error_correction.html
accessed on 22/10/2017 at 11:30 AM.
[3]. Data Encoding http://www.thonky.com/qr-code-tutorial/data-
encoding accessed on 22/10/2017 at 1:30 PM.

21. THANKYOU