2001 Conference Proceedings
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Accessing Interactive Television: It's More than Meets the
Eye
Tom Wlodkowski
Project Manager, Access to Convergent Media Project
CPB/WGBH National Center for Accessible Media
WGBH Educational Foundation
125 Western Ave.
Boston, MA 02134
voice: 617 300-3486
fax: 617 300-1035
E-mail: tom_wlodkowski@wgbh.org
Background
The onset of digital television - with its capability to deliver
multiple programs and interactive services simultaneously - will
cause the most significant change to this medium since its launch
in 1939. Imagine accessing streaming data about a candidate for
President while watching the final in a series of presidential
debates a week before the election. If steps are not taken now to
address accessibility, the potential exists that people with
disabilities will loose ground in gaining access to all that the
information age has to offer.
This paper highlights existing roadblocks preventing individuals
who are blind or visually impaired from effectively using
convergent media technologies such as a digital cable set-top box
(STB) or stand-alone digital television receiver. Solutions to
improve usability of these technologies are also discussed. This
work is a product of the CPB/WGBH National Center for Accessible
Media (NCAM) Access to Convergent Media Project.
Introduction
Convergent media" refers to the growing body of programming and
services arising from the intersection of broadcast and cable
television, enhanced/advanced/digital television, computers, and
Internet technology. The evolution of digital television and
other broadband technologies will change the way people access
current information. While convergence technologies will open
many new doors, the potential exists that these technologies will
close as many doors for individuals who are blind or visually
impaired if steps are not taken to ensure some alternate means of
navigation in this graphic-rich environment.
The old paradigm of passive television viewing is rapidly
fading. Soon television will deliver an array of interactive
educational, civic, commercial, and entertainment services to the
homes, classrooms, workplaces, and communities of all Americans.
Television itself will be changing. In the analog world,
broadcasters are limited to one program stream. In the digital
world, up to four program sources can be aired simultaneously. In
order to make a selection from the wide array of available
programs and services, the user will be required to interact with
a graphics-rich electronic program guide (EPG). The EPG is an
integral component in digital set-top boxes and over-the-air
digital television receivers.
The Access to Convergent Media Project is focusing on the
set-top box and the electronic program guide for several reasons:
1) the STB is currently the most affordable option to access
convergent media, 2) cable STBs, due to their reliance on wires
to send and receive data, will offer more interactive services
than terrestrial systems and 3) many solutions developed for the
EPG are likely to enable blind users to successfully interact
with other services delivered through the set-top box such as
e-commerce, web browsing, program enhancements, and other
interactive features.
A Viewer's Experience
The profile below broadly paints what NCAM envisions as an
effective alternate user interface for an electronic program
guide. NCAM has developed a prototype audio-enabled EPG based on
this profile, Project staff will use this presentation to
demonstrate the prototype in order to generate feedback on our
approach from consumers and experts in the field of assistive
technology. The prototype will ultimately be used to demonstrate
conventions for designing a universally accessible EPG to
broadcasters, cable and direct broadcast satellite providers and
consumer electronics manufacturers.
It's 10 p.m. and Joe, who is blind, wants to watch television.
Joe's wife and son, both of whom are sighted, are not available
to read the local program guide. Even if they were available, Joe
thrives on being independent and doesn't want to rely on his
family to access this information. Sure, he could surf channel by
channel and wait at each stop to figure out by program audio what
the current program is. That is exactly what he and other blind
viewers have had to do for years because the traditional program
guide was purely visual. And in the 200+ channel universe, Joe
would spend all of his time surfing rather than enjoying a
specific program. But now Joe is no longer forced to surf
aimlessly, thanks to the enhanced services available through his
new digital set-top box (STB). Joe's cable company offers an STB
that can communicate the information displayed on the screen via
spoken audio. For the first time, the electronic program guide
(EPG) is accessible.
When Joe turns on his television, he discovers that the access
features on the STB have been turned off. Upon pressing the menu
key on the remote control, a voice prompts him to "select a
configuration." The assistive audio also mentions how to select
from the list of stored STB configurations. Joe selects Audio
Navigation, which puts the STB in a mode designed to allow blind
users to successfully interact with it. Because Joe is an
experienced user of voice navigation, his previously stored
personal configuration includes a setting to drive the speech
synthesizer in fast mode, to minimize the time it takes to read
text. (His mother, who is also blind, needs the audio to be
slower, so her configuration indicates a slow listening speed.)
Now the STB presents the main menu where a list of available
choices is read aloud. Using the STB remote control, Joe steps
through the menu and selects the EPG. Once inside the EPG, the
audio presents several options for interaction with EPG content -
Search, Read from current time (10 p.m.) forward, Read by date,
etc. Joe selects the current time option.
If a sighted user selected this option without the access
features enabled, they would be presented with a multi-column
display. The screen may have channels in a vertical column on the
left, a timeline (10:00, 10:30, etc.) across the top, and next to
the channel column, a second vertical column with program
information for each channel. If the audio output simply read
this display, Joe would hear information out of context. With
this in mind, the accessibility mode acquires the data and
presents it in linear format. The audio reads:
10 p.m. (brief pause)
Channel 2---CNN Larry King Live
Channel 3---FOX Baseball: Red Sox vs. Yankees
Channel 4--- ... (and so on)
Joe can interrupt the sequence at any time by simply hitting the
arrow keys on the remote. With no interruption by the user, the
STB continues reading linearly until the list of offerings is
complete, wrapping from 10:00 to 10:30 to 11:00, etc. A single
down arrow interrupts the audio output, and puts the STB into a
suspended state. A single down arrow would now read the next
channel entry, wherever the EPG was interrupted. Two down arrows
in quick succession moves to the next time slot (10:30, the next
major table discontinuity). Three down arrows in quick succession
repositions to the next date, etc. After a slight pause, the
voice continues announcing the list of offerings available at
that date, time, and channel.
[Note: this type of navigation is friendlier to all types of
users, not just blind users, since it allows the user to minimize
unnecessary data presentation during navigation.]
Joe decides to watch the Red Sox and interrupts the audio by
clicking the Enter key on the STB remote when channel 3 is
announced. After a while, Joe decides to watch another program.
This time he decides to search the EPG for a specific program
type. Joe is a musician and is curious if there are any music
related offerings. He enters the EPG, and selects "Search" from
the opening screen. The STB announces a list of program genres.
Using the STB remote, he steps through the list and selects
Music. Once the search results are in place, Joe is presented
with the same choices as before -- Read from current time (now 11
p.m.) forward, Read by date, etc. Read from Current Time Forward
is selected and the audio begins, first announcing the time, then
reading the channel and corresponding program information. Joe is
intrigued by a documentary on Charlie Parker airing on A&E.
Wanting more information on this program, he highlights the
program and double-clicks the "enter" key on the remote. In this
mode, Joe hears a detailed description of the program. He decides
to watch the program, and disables the EPG by clicking Enter for
that selection, A&E, Channel 33, on the EPG.
Key Components
Several components are necessary in order for an Electronic
Program Guide (EPG) delivered via a digital set-top box to be
accessible to a blind or visually impaired user:
Support of multiple user configurations
At it's highest level, the STB must be modal, allowing users to
easily toggle between the default "visual" mode and "access"
mode, the latter of which causes the STB to present data in a
non-visual manner (most likely audio). This type of support will
ensure the STB meets the needs of all members of the household.
Accessible navigation Scheme
Blind users must be able to step item by item through a menu of
choices to make a selection. The highlighted item must be
announced. Since virtually all current EPGs use the up, down,
left and right arrow keys on the remote control to step through
the list of available programs and services, this scheme should
work for blind or visually impaired users assuming the item that
has focus is announced. The active menu item should also have
visual focus in order to improve usability by low vision users.
One solution to illustrate visual focus is to draw a box around
the active item. Additionally, consistent shortcuts programmed
into the use of the few navigational buttons can greatly enhance
the usability of the remote for all users. A shortcut like
double-clicking to indicate movement through major table
sub-headings is a helpful navigation tool for blind and sighted
viewers alike.
Assistive audio
Implementation of assistive audio may be accomplished through any
combination of synthetic and digitized speech. The speech
component could be stored locally on the STB, or stored on a
cable "headend" server and loaded into the STB RAM as needed.
Whichever source type/delivery method is used, some audio native
to the STB will likely be required. This will insure that a blind
user has support for invoking the access features, from simply
turning accessibility features on, to selecting amongst multiple
user configurations which are customized to each of the several
members of a household.
When playing assistive audio, it is important for the STB to
temporarily fade or completely interrupt the conventional program
audio, so that the assistive audio can be clearly heard and
understood. Additionally, the ability to adjust the rate and
verbosity of the assistive audio can greatly enhance the
usability of this feature.
Presentation logic
In addition to providing assistive audio, the accessibility mode
needs to get at the underlying data of the EPG and render it in a
user-friendly manner. Simply announcing existing on-screen
textual information is not always the best way to make that
information accessible. For example, while a table format may be
the most efficient use of screen space for presenting program
guide content for sighted users, blind users benefit from a
linearized presentation. When thinking about audio presentation
of information, the software designer must endeavor to forget the
"look" of the data, and concentrate on the "feel" of the data.
Additional Efforts
NCAM through its DTV Access Project is also looking at
accessibility issues concerning the transmission and reception of
digital television content. The main focus of the DTV Access
Project is to encourage implementation of advanced closed
captioning and video description services in professional and
consumer digital television systems. the Project has created test
materials, authored standards and guidelines and participated in
recent FCC rulemakings in support of these services. With funding
from the Corporation for Public Broadcasting, the project also
assists the nation's public television stations in maintaining
and enhancing captioning and description services as they
transition from analog to digital broadcast facilities. A brief
overview of the DTV Access project will be provided at the
conclusion of this presentation.
Funding for NCAM's DTV Access and Access to Convergent Media
projects is provided by the National Institute on Disability and
Rehabilitation Research (NIDRR), U.S. Department of Education.
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