Barcodes and QR codes are machine-readable codes that contain information about an object. Barcodes use a pattern of bars and spaces that are scanned by light, while QR codes use a two-dimensional matrix that can be scanned by smartphones. Common barcode types include Code 39 for non-retail uses and Code 128 for shipping and retail, while QR codes are most commonly used with mobile devices to link to websites or send SMS messages. Both barcodes and QR codes require a quiet zone around the code and are interpreted by scanners or smartphone apps that convert the light reflection or image into readable digital information.

1. Barcode/QR Code
Technology

2. Definitions
• Barcode - a code consisting of a group of printed and variously patterned
bars and spaces and sometimes numerals that is designed to be scanned
and read into computer memory and that contains information (as
identification) about the object it labels.
• QR Code - a matrix barcode (or two-dimensional code), readable by QR
scanners, mobile phones with a camera, and smartphones.
• Scanner – a device that interpret different imagery, in this case: barcodes.

3. Different Codes
Code 39
• Defines 43 Characters.
• Typically used in non-retail areas.
• Arguably the simplest barcode.

4. Different Codes
Code 128
• Defines the entire 128
ASCII character set.
• Typically used in
shipping/retail.

5. Different Codes
QR Code
• Most commonly used
barcode as of recent
especially with mobile
phones.
• Has various numbers of
functions: linking to
websites, send SMS
functions, etc.

6. How does a
scanner/smartphone
interpret a barcode?
• Each barcode is interpreted similarly and yet also slightly
differently as well.
• Barcodes also happen to be less complex that QR Codes.
• Barcodes can use scanners, whereas QR Codes require
something else (i.e smartphones, computer, game machines)

7. No/Quiet Zones
• For all commonly used barcodes, each has a no or quiet zone.
Each one varies.
• In general, these must not be covered or the scan of the
barcodes will not work.
• For QR Codes, there are no zones as well as a quiet zone.
• With Codes 39 or 128, they have a quiet zone surrounding it.
Quiet Zone

8. No Zones
QR Code
• Position Markers
• Format
• Version Number
• Alignment Marker

9. Barcodes
• Barcode scanners are made of 3
different parts: an illuminator, a
convertor, and a decoder.
• The illuminator shoots out a line
of light (typically red) at the
barcode.
• Light will reflect from the barcode
(from anywhere that is not black)
in the form of a wave.
• The convertor converts the wave
into a readable form for the
device.
• Decoder reads the converted
information.
Light from Scanner
Barcode
Light Reflection

10. QR Codes
• Certain applications on a smart
phone / portable gaming device
can scan QR codes (i.e ZXing on
Android)
• Instead of bouncing off an image
via light, QR Codes are interpreted
from a picture skipping the light
wave process.

11. QR Codes
• Interpretation of the code is that
excluding the no zones, each
black module is a 1 bit and a
white one is a 0 bit.
0 1

12. QR Codes
• 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.

13. QR Codes
• Error Correction
• This allows other images to
be placed into the code
without any issues.
Still works!

14. Conclusion
• What barcodes and QR codes are.
• A brief history of barcodes.
• The different kinds of barcodes.
• How they work.

15. Questions
?