2 State of the Art
Recent technological developments provide technical assistance that helps to support
visually impaired people in their daily tasks and improves their quality of life. In this
context, sensory substitution systems [1–4] are devices that allow information normally
acquired by a defective sensory organ and restored to another perceptive modality. For
the visually impaired, it consists of transmitting visual information via the auditory or
somatosensory system
First, the visuo-tactile substitution devices convert a visual image into tactile information. There are many devices such as the TVSS [5], TDU [6]. These tools are efficient in
the recognition of simple forms, the possibility of reading and localization [7].
Moreover, the visuo-auditory substitution devices are based on the transformation
of visual image into auditory information. Thanks to auditory system, visually impaired
people use sounds for navigation that inform them about the environment and protect
them from obstacles. There are many devices such as the Voice [7], PSVA [8], the Vibe
[9], and See Colour [10].
These visual substitution systems are using the translation of visual information
into another auditory sensory in order to assist visual impaired people. However,
existing system needs hard equipment and sometimes the visual impaired should
handle it in a backpack.
In addition, new technologies such as mobile phones or smartphones provide
technical assistance to support the visually impaired in their daily tasks and aim to
improve their quality of life. These devices are equipped with touch screens that ensure
better user experience. In fact, they are more adaptable to the visually impaired people
using a guiding system for way finding. So that, using a smartphone and its integrated
camera, the system is able to detect objects such as the panels [11].
Another technology was presented in literature, which is the Near Field Communication (NFC). NFC is one of the newest technologies in the communication area. It
has a rapid progress in mobile devices and an increase number of smartphones
equipped with NFC readers. This technology combines identification and interconnection and enables secure communication between electronic devices [12]. In fact, the
user has simply to touch the NFC tagged object in order to obtain detailed information.
Besides, there are other visual substitution applications based on voice and haptic
replication. The user receives information when entering or sliding the finger on the
screen using a screen reader that converts text to speech and ensure reading and
navigating through the contents [13].
In addition, haptic is a technology that provides tactile feedback. For tactile-based
interfaces [14], haptic can make the user feel and visualize the shape of an element
without looking at the screen. It can also provide comments when the finger reaches the
limit of an element or button.
The experiments results in literature [15] illustrate the ability of blind and visually
impaired people to use assistive mobile application in order to locate the guide signs
with an auditory feedback.
396
H. Jabnoun et al.
Recent technological developments provide technical assistance that helps to support
visually impaired people in their daily tasks and improves their quality of life. In this
context, sensory substitution systems [1–4] are devices that allow information normally
acquired by a defective sensory organ and restored to another perceptive modality. For
the visually impaired, it consists of transmitting visual information via the auditory or
somatosensory system
First, the visuo-tactile substitution devices convert a visual image into tactile information. There are many devices such as the TVSS [5], TDU [6]. These tools are efficient in
the recognition of simple forms, the possibility of reading and localization [7].
Moreover, the visuo-auditory substitution devices are based on the transformation
of visual image into auditory information. Thanks to auditory system, visually impaired
people use sounds for navigation that inform them about the environment and protect
them from obstacles. There are many devices such as the Voice [7], PSVA [8], the Vibe
[9], and See Colour [10].
These visual substitution systems are using the translation of visual information
into another auditory sensory in order to assist visual impaired people. However,
existing system needs hard equipment and sometimes the visual impaired should
handle it in a backpack.
In addition, new technologies such as mobile phones or smartphones provide
technical assistance to support the visually impaired in their daily tasks and aim to
improve their quality of life. These devices are equipped with touch screens that ensure
better user experience. In fact, they are more adaptable to the visually impaired people
using a guiding system for way finding. So that, using a smartphone and its integrated
camera, the system is able to detect objects such as the panels [11].
Another technology was presented in literature, which is the Near Field Communication (NFC). NFC is one of the newest technologies in the communication area. It
has a rapid progress in mobile devices and an increase number of smartphones
equipped with NFC readers. This technology combines identification and interconnection and enables secure communication between electronic devices [12]. In fact, the
user has simply to touch the NFC tagged object in order to obtain detailed information.
Besides, there are other visual substitution applications based on voice and haptic
replication. The user receives information when entering or sliding the finger on the
screen using a screen reader that converts text to speech and ensure reading and
navigating through the contents [13].
In addition, haptic is a technology that provides tactile feedback. For tactile-based
interfaces [14], haptic can make the user feel and visualize the shape of an element
without looking at the screen. It can also provide comments when the finger reaches the
limit of an element or button.
The experiments results in literature [15] illustrate the ability of blind and visually
impaired people to use assistive mobile application in order to locate the guide signs
with an auditory feedback.
396
H. Jabnoun et al.