Introduction
Different
assistive tools and facilities described in the previous section
have been designed for people with different kinds of disabilities.
Some of the facilities are purely external tools, such as hardware
and equipment designs which do not affect the design of web pages.
In general, tailoring of web pages is required for people with visual
and hearing disabilities. However, if such design considerations
are included in the initial design of web pages, tailoring in future
may not be required and the website will well serve ordinary customers
as well as those with disabilities.
To
make web contents accessible, one of the key factors is to put it
in text format or provide a text equivalent of the web content.
It is such text content / text equivalent that many of the assisting
software / hardware can operate on. Such assistive tools will transform
the text contents for presentation in other media e.g. sound, braille
pattern or visually displayable texts.
One
simple approach is to produce a separate text version of the web
pages. The text version will have no graphics and preferably all
text contents are arranged in a linear fashion. Another approach
is to enhance the existing pages so that text descriptions are supplied
and alternate text equivalents of multimedia contents are provided
on a need basis. (The section Tips for
making your web pages more accessible will discuss how such
features could be incorporated). Another emerging approach is to
maintain a single graphic version of the web content and use programs
to dynamically generate a text-only version on demand.
Pros and Cons of the various approaches
It
is evident from the above that some sites may choose to produce
a separate text version of their web contents while others may choose
to enhance their existing web pages and provide text equivalents
when needed. A separate pure text version can cater for the needs
of more Internet users while keeping one version of the site helps
to reduce the maintenance effort required. Each option has its pros
and cons including -
Separate
text version
| Pros |
Cons |
- The
text version is more accessible and meets the needs of more
people e.g. those with slow modems, less sophisticated browsers,
users with low-vision who rely on magnification and for
congnitively impaired users who receive information better
if it is in a less clustering and linear presentation. It
is also more convenient for the vision impaired as they
can just focus on the text version of the site.
-
Each web page of the site can be duplicated and converted
to its text equivalent more mechanically without identifying
which part of the site has to be modified. All graphic elements
can be dropped or translated. However, rendering of tables
and multi-media contents into its text equivalent are still
required.
- Other
multi-media features can be fully exploited on the graphic
version of the site without great concern for its accessibility.
|
- More
effort has to be spent on subsequent maintenance of the
pages. All update must be made both to the graphic and text-only
version of the site.
- Tailoring
of search function required otherwise each search result
may come back with 2 versions (graphic version and text-only
version) of the same page.
- Increase
the chance of asymmetrical contents due to omitted update
in the text-only version of the web page.
|
'Enhancement-in-place'
with separate text-equivalent on a need basis
| Pros |
Cons |
-
Save effort in producing a full version of the text equivalent
of the site. Text equivalent is required only for selected
sections of the site e.g. complicated tables, graphs etc
- Save
some effort in subsequent maintenance of the duplicate version
of the site
- Minimise
the chance of asymmetrical contents (due to omitted updates)
as compared to the 'separate text version' approach.
|
-
Need more understanding of the accessibility mechanism by
the web masters and the vendors to identify the type of
tailoring required.
|
Program
generated text-only version
| Pros |
Cons |
-
Only 1 version of the web content needs to be kept. This
will save subsequent effort in the maintenance of the site.
-
Minimise the chance of asymmetrical contents (due to omitted
updates) as the separate text version is generated dynamically
from the graphics version only when needed.
|
-
Programming effort is required. The provision of a separate
text-equivalent of some contents, e.g. complex tables, multi-media
contents with important information conveyed still need
to be addressed.
|
In
general, web sites that are already heavily text-based may consider
the use of the 'enhancement-in-place' approach while websites with
heavy multi-media contents may consider the use of a separate text
version of the site. Website designers may decide which option to
use depending on the characteristics of the web contents.
|
|