The people with typical
vision get the data dynamically reliant on vision in everyday living. Unfortunately,
low vision people has a visual
impairment that interferes with their ability to perform daily activities so
that they obtain the
information by reading standard
print or enlarged print and through listening.
In a survey conducted by World Health Organization (WHO) in 2010, the statistical result showed that there were
approximately 1 ,
246 million people
A probable of 19 million of the low visual impaired were children
aged under 15. Every year, it grows by up to 2 million worldwide.
Because of low visual
disability, the abilities for performing daily tasks like reading, walking,
driving, or recognizing objects, finding
and interacting with surrounding world are limited or unfair. They
need assistance from their family members and friends. If the assistive
technologies can support low visually impaired people in at least one of daily
tasks, it is going to make a very relevant social impact 2.
For low visually impaired people, Large print type should be used,
preferably 18 point, but at a minimum 16 point. Scalable fonts on the computer
make this easy to do.
Corrective lenses are
glass or plastic worn on or in front of the eye that are used to improve the focus and correct the blur. They
are mainly used to treat myopia, hyperopia, presbyopia and
astigmatism3. However, those corrective lenses are only useful for low visually
Some of the technologies
have been developed for the solution of walking assistance in the following
aspects like obstacle avoidance, navigation and orientation, and accessing
environment. The most traditional mobility tools is the long cane (i.e., white
cane) which is used to detect obstacles in the path of the
Low vision is often defined as visual impairment that interferes with a
person’s ability to perform everyday activities. Most low vision is caused by eye diseases and health conditions such
as cataracts, glaucoma Some low vision is from birth defects or injuries. So
that they are unable to perform basic
everyday tasks such as reading, writing, driving and sitting in front of the
television or a computer screen.
number of devices have been developed to support the visually impaired to
access public places and locations. For example, audible indicators are used to
alert when doors open and cross the pedestrian26.
Recently, several aid
systems have been developed to help low vision
impaired people read text from natural
sceneries or product labels 29 – 35.
should be developed to increase the accessibility for verbal information like
books, newspapers, documents, bills, and menus. Magnification
method is useful only for low vision people and not for those who are
Information SYstem (DAISY) aims to provide digital audio books for people with
print disabilities 38. At present, eXtensible Markup Language (XML) and MP3
are recommended as DAISY standard to represent text content and audio content.
An XML format can be easily converted into another format, such as Braille,enlargetext
and audio format. A screen reader is an interface which bridges the computer
operation system and the user’s command 39 – 41. They are a form of assistive technology that allow
visually impaired people to read the content displayed on the computer screen
through a speech synthesizer or Braille display. Visually
impaired people to access the information
mainly through: (1) Enlarging, The text and Pictures. (2) hearing, the audio.
A printed book often
needs to be scanned and recognized before translating it into Braille, or
speech44. LookTel 47 is a software developed to detect and recognize
objects such as packaged goods, CD covers, bank notes and more.
The above mentioned
technologies are developed to assist the low vision impaired in navigation, reading,
and object recognition. The degree of visual disabilities and the level of
personal abilities, thus for different individuals their needs are very
Low visually impaired people, especially blind
people, are difficult to access visual information unless they are represented
non-visually, such as with speech and Braille.
Almost all of the
schools for the low visually impaired
need enlarged books for teaching and studying. However, in 80% of the blind
schools, there is no department for producing tactile graphic and enlarged
books for teaching and learning materials 48. Most of the work for producing
enlarged teaching materials is done by teachers while some of the work is done
by volunteers. Technologies developed for automatically reading scene text play
a key role in assisting people with visual impairment, especially low vision
people, to find locations.
Up to now, several
portable or wearable camera-based devices have been proposed for assisting the low
visually impaired to read text in scenery. It is necessary for us to develop a
technology for automatically reading text from scene images with high accuracy.
Our aim is to
(1) Develop a
technology that supports the translation of text into enlarged format and
(2) Develop a
technology for automatically reading text from natural scenery.
(3) Improve the
accessibility for textbooks to low visually impaired students.
(4) And To support the low
visually impaired to access text information in the surrounding environment.