This document discusses gesture recognition, including what gestures are, types of gesture recognition like facial, hand, and sign language recognition. It covers the basic working of gesture technology and types of gesture sensing technologies such as device, electrical field, and vision-based sensing. Some applications of gesture recognition discussed include controlling devices, sign language translation, and assisting with patient rehabilitation. Challenges to gesture recognition are also mentioned such as lack of standard gesture languages and issues with robustness due to lighting and noise factors.

1. By
Sandeepreddy

2. 
contents
 What are gestures
 Types of gestures
 What is Gesture Recognition ?
 Working
 Types of Gesture Recognition
 Types of Gesture Sensing Technology
 Technology Behind It
 Uses Of Gesture Recognition
 Gesture Recognition Challenges
 Conclusion

3. Military air marshals use
hand and body gestures
to direct flight
operations aboard
aircraft carriers.


4. What is Gesture Recognition ?

 Interface with computers using gestures of the
human body, typically hand movements.
 Gesture recognition is an important skill for robots
that work closely with humans.
 Gesture recognition is especially valuable in
applications involving interaction human/robot for
several reasons.

5. Basic working of Gesture Technology

6. Types of Gesture Recognition
Facial Gesture Recognition

 Facial Gesture Recognition
creates an effective non-contact
interface between
user and their machines
 The goal of facial Gesture
Recognition is to make
machine effectively
understand human
 emotions , regardless of
the countless physical
differences between
individuals

7. Hand Gesture Recognition

 Hand gesture recognition technology allows operations of
complex machines using only a series of fingers and
hand movements , eliminating the need of physical
contact between operator and machine

8. Sign Language Recognition

 Certain types of gesture
recognition software can
transcribe the symbols
represented through
sign language into text
 Effective sign language
recognition can help the
deaf people to
communicate with both
other people as well as
the machine

9. Types of Gesture Sensing Technology
Device sensing technology
 Device-based techniques
use a glove, stylus, or
other position tracker,
whose movements send
signals that the system
uses to identify the
gesture.
 The glove is equipped
with a variety of sensors
to provide information
about hand position,
orientation, and flex of
fingers.

10. Electrical Field Sensing Technology
 Proximity of a human
body or body part can be
measured by sensing
electric fields .
 These measurements can
be used to measure the
distance of a human hand
or other body part from an
object; this facilitates a
vast range of applications
for a wide range of
industries.

11. Vision based technology
There are two approaches to
vision based gesture
recognition:
 Model based techniques:
They try to create a three
dimensional model of the
users hand and use this for
recognition.
 Image based methods:
Image-based techniques
detect a gesture by
capturing pictures of a
user’s motions during the
course of a gesture.

12. 
Wired gloves:-
 These can provide input to the computer
about the position and rotation of the hands
using magnetic or inertial tracking devices.
 The first commercially available hand-tracking
glove-type device was the Data
Glove , a glove-type device which could
detect hand position, movement and finger
bending.
 This uses fiber optic cables running down the
back of the hand. Light pulses are created
and when the fingers are bent, light leaks
through small cracks and the loss is
registered, giving an approximation of the
hand pose.

13. 
Stereo cameras:-
 A Stereo camera is a camera that has
two lenses about the same distance
apart as your eyes and takes two
pictures at the same time. This
simulates the way we actually see
and therefore creates the 3D effect
when viewed.
 Using two cameras whose relations
to one another are known, a 3D
representation can be approximated
by the output of the cameras.

14. Depth-aware cameras.

 Using specialized cameras such
as structured light or time-of-flight
cameras, one can generate a depth
map of what is being seen through
the camera at a short range, and use
this data to approximate a 3d
representation of what is being seen.
 These can be effective for detection
of hand gestures due to their short
range capabilities.

15. Thermal cameras:
 An infrared camera is a device that
detects infrared
radiation(temperature) from the target
object and converts it into an
electronic signal to generate a thermal
picture on a monitor or to make
temperature calculations on it.
 The temperature which is captured
by an infrared camera can be
measured or quantified exactly, so
that not only the thermal behavior can
be observed but also the relative
magnitude of temperature related
problems can be recognized and
noted.

16. 

17. Controller –based gestures:-
 These controllers act as an extension of the body so that when
gestures are performed, some of their motion can be
conveniently captured by software.
 Mouse gestures are one such example, where the motion of the
mouse is correlated to a symbol being drawn by a person's
hand, as is the Wii Remote, which can study changes in
acceleration over time to represent gestures.

18. 
Socially assistive robotics:-
By using proper sensors worn on the body of a
patient and by reading the values from those
sensors, robots can assist in patient
rehabilitation. The best example can be stroke
rehabilitation.
Sign language
recognition:-
Just as speech recognition can
transcribe speech to text,
certain types of gesture
recognition software can
transcribe the symbols
represented through sign
language into text.

19. For systems where the act of finding or

acquiring a physical controller could require
too much time, gestures can be used as an
alternative control mechanism. Controlling
secondary devices in a car, or controlling a
television set are examples of such usage.
Virtual controllers:-
Remote control:-
Through the use of gesture
recognition, remote control with the
wave of a hand of various devices is
possible.

20. Gesture Recognition Challenges

 Lack of Gesture Language
Different users make gestures differently, causing
difficulty in identifying motions
 Robustness
Many gesture recognition systems do not read motions
accurately or optimally due to factors like insufficient
background light, high background noise etc

21. Conclusion

 The importance of gesture recognition lies in
building efficient human machine interaction.
gesture recognition promises wide-ranging
applications in fields from photojournalism through
medical technology to biometrics.

22. 
Thank u