1998 Conference Proceedings
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OPTIMIZING READING FOR VISUALLY IMPAIRED PEOPLE
James C. Bliss and Peter Young
JBliss Imaging Systems, 650 Saratoga Ave.,
San Jose, CA 95129 (408)246-5783
In today's world one encounters information from a variety of
sources, printed and electronic, and in wide range of type sizes,
type fonts, colors, and formats with pictures and graphics
imbedded in creative ways. While this variety makes the
presentation more interesting and information more readily
available for the viewer with normal eyesight, it can present
problems for people with visual impairments.
For years magnification has been the main remedy to help
people with low vision read. Optical magnifiers were the first
generation of low vision assistive products and video magnifiers
are the second generation. However, magnification is not the only
modification of print that can make it more readable for low
vision people. Research (1,2,3) has shown that type font, letter
spacing, and color can effect letter recognition in different
ways depending on the visual impairment. In addition, with
specific visual impairments reading speed can be significantly
improved if text is scrolled or moved across the field of view in
While magnification alone can make documents readable that are
otherwise unreadable with certain visual impairments, this
reading is often slow, tedious, and fatiguing. These realizations
led us to the development of a document reading system aimed at
making reading as fast and easy as possible by people with low
Since visual impairments vary widely, this goal requires the
reading system to be adjusted to accommodate the user's vision.
For example, optimal adjustment for a person with macular
degeneration can be very different than the optimal adjustment
for a person with central field tunnel vision.
The following video, which was shown on KRON TV in the San
Francisco Bay Area on December 3, 1997, illustrates the reading
system, called VIP(TM) (for Versatile Image Processor), which we
The VIP Reading System has the following design features:
- Text attributes of font, color, size, and letter spacing are
adjustable over wide ranges to provide an optimal viewing
configuration for most visual impairments.
- Any of the following views can be selected for optimal
reading speed given the visual impairment and the document:
- 1) Marquee View -- The text is reformatted into one long line
which scrolls across the screen at a rate controlled by the user.
Since there are not ends of lines and beginnings of next lines,
no time is lost changing lines, which can be very significant,
especially when large magnification is needed.
- 2) RSVP View (for Rapid Serial Visual Presentation) --The
text is presented one word at a time at the same location. The
location can be such that the word is left justified, center
justified, or right justified. Each word is presented for a equal
length of time controlled by the user, or if synthetic speech is
turned on, for a length of time equal to how long it takes to say
the word at the speaking rate determined by the user.
- 3) Word Wrap View -- For the chosen magnification and letter
spacing, a screen of text is presented with lines as long as
possible without splitting words, and as many lines as can fit on
the screen. This screen can scroll vertically, or stepped one
screen at a time. Speech can be turned on with the word or line
highlighted that is being spoken.
- 4) Image View -- This view shows an image of the document in
the upper part of the screen. An image of one line is magnified
an adjustable amount and scrolled across the bottom of the
screen. The corresponding line is highlighted in the upper part
of the screen. Line changes are automatic. Optical character
recognition is not used in this view, so the images presented are
direct views of the images acquired by the scanner, with image
processing to smooth the line strokes and to separate the
- 5) Locator View -- The purpose of this view is to locate and
reposition the starting point for any of the views above. It
consists of a full image of the page with a small magnifying
window superimposed. This magnifying window can be positioned
anywhere on the page and this position determines the starting
point for any of the views above.
- Up to 99 different user configurations can be stored and
quickly retrieved for multiple user situations or situations in
which different configurations are preferred for different
- There is a picture viewing function which allows full color
pictures to be displayed with adjustable magnification.
- There are three user levels to accommodate different needs,
available learning time, and abilities.
- 1) ezVIP(TM) -- At this level reading of scanned documents is
controlled with the two mouse buttons, one to scan and the other
to start and stop the scrolling and speech.
- 2) VIPinfoSoft(TM) -- This intermediate level adds a library,
locator screen, and picture viewing. Control is with the mouse
and the number pad on the keyboard.
- 3) VIPinfoSoft Plus(TM) -- This advanced level adds e-mail,
address book, auto dial, memo editor, printing, and
cut/copy/paste commands to/from other application programs
through the clipboard. Control is with the mouse and full
- Information from the following sources can be accessed with
- 1) Printed documents -- a wide range of printed documents can
be successfully read: books, newspapers, magazines, etc.
- 2) e-mail -- messages can be received and read is the same
fashion as printed documents. Messages can be written with the
built-in large print/speech editor and sent as new, replies, or
- 3) CD -- text stored on CDs can be read in the same fashion
as printed documents, making scanning unnecessary.
- 4) Camera -- with the video camera accessory, the system
operates as a video magnifier (CCTV) plus frames can be stored,
colors changed, and enlarged electronically. This accessory is
used to view three dimensional objects, such as prescription
bottles, cans, etc., and to provide magnified image feedback when
- 5) Internet -- with the VIPinfoNet(TM) program, web sites can
be read in the same fashion as printed documents. In addition
links can be downloaded, bookmarks placed, and tables viewed by
row and column.
- The user interface is designed to be easy to use by people
with visual impairments and with no previous computer experience.
No pointers, pull down menus, or radio buttons are used because
these components are difficult for many visually impaired
persons. Instead, menu selections are placed on large virtual
buttons labeled with large print in the four corners of the
screen. These virtual buttons correspond to the four real buttons
in the four corners of the number pad (7,9,1,and 3). Adjustment
of a menu item (e.g., size, letter spacing, etc.) is done with
the 4 and 6 keys.
- All standard hardware is used in VIP systems, so users can
purchase either software alone, or complete systems which can
also be used normally as a computer. VIP software programs are
application programs running under Windows 95.
- VIP scanned document reading programs include an Optical
Character Recognition (OCR) engine (Textbridge(R) by Xerox) and a
synthetic speech engine (Flextalk(R) by AT&T). VIPinfoNet
includes the Flextalk synthetic speech engine.
- The following Help systems are built into VIPinfoSoft,
VIPinfoSoft Plus, and VIPinfoNet:
- 1) Pressing the help key (number 5 on the number pad)
displays a large print screen picture of the number pad with the
keys active at that point in the program indicated. In this help
mode, a spoken and large print explanation what a key does can be
obtained by pressing the key. The second consecutive press of the
key performs the action.
- 2) There is on-line help available by pressing Function key
- 3) A full manual can be stored in the built-in Library and
viewed in the same way as any scanned document.
- 4) VIPinfoNet has a mode for learning the keyboard commands.
When a key is pressed in this mode, the function that key
performs is explained in speech without the action being
CONCLUSION AND FUTURE TRENDS
Even though VIP systems have been available only for a
relatively short time, there are already many VIP Reading Systems
being used in individual homes and offices, in libraries, in
schools, and in centers for people with visual impairments.
Compared to video magnifiers (CCTVs), VIP Reading Systems are
enabling faster and easier reading and much greater functionality
at a similar cost. By basing VIP Reading Systems on PC technology
rather than television technology, future developments and uses
of the hardware are unlimited, compared with the dead-end future
of video magnifiers.
Therefore, the future trend will be to replace video
magnifiers (CCTVs) based on television technology with PC based
reading systems which are becoming the third generation of
systems to assist low vision readers.
1. A. Arditi, K. Knoblauch, and I. Grunwald, "Reading with
fixed and variable pitch", J. Opt. Soc. Am. A, Vol. 7, No. 10,
pp. 2011-2015, Oct. 1990.
2. G. E. Legge, G. S. Rubin, D. G. Pelli, and M. M. Schleske,
"Psychophysics of Reading-II: Low Vision", Vision Res., Vol. 25,
No. 2, pp.253-266, 1985
3. J. S. Mansfield, G. E. Legge, and M. C. Bane,
"Psychophysics of Reading-XV: Font Effects in Normal and Low
Vision", Investigative Ophthalmology & Vision Science, July
1996, Vol. 37, No. 8, PP 1492-1500.
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