Office Hours: Image Description
Presented by the DIAGRAM Center and the
WGBH National Center for Accessible Media (NCAM)
October 24, 2013
What to expect today
 Answers to questions regarding image descriptions
— questions and images collected beforehand
— examples of difficult-to-describe images and charts
— approaches that can be adapted
 multiple ways to describe
— Q+A
Question 1: schematic drawings
 Schematic drawings are often an issue to describe. What are
the best practices for these?
— similar to flow charts
 flow chart with complex paths
 process diagram as a flow chart
— provide a summary and then a list
— simple flow charts can be summarized without a list
Question 1: schematic drawings
A schematic diagram of a simple circuit with a switch.
 Three batteries form a power pack. Each battery is represented by a pair of long
(positive) and short (negative) lines.
 A wire, represented by a straight line, leaves the positive terminal of the power
pack and connects to a toggle switch, which is in the open position. The open
switch is represented as a break in the wire, lifted at a diagonal.
 The wire continues to a light, which is represented by a zigzag line with a circle
around it, and then back to the negative terminal of the power pack.
Question 1: schematic drawings
A schematic diagram of a simple circuit with a switch. The
circuit is composed of three batteries, a toggle switch and a
light. The switch is in the open position.
Question 2: complex image
 Many diagrams from biology texts are three-dimensional and
contain multiple steps. Do you have advice about how to
create audio descriptions or tactile versions of these?
Question 2: complex image
Question 2: complex image
 Summarize the illustration briefly, then provide details
 If color is used to convey information, include that in the
description
— otherwise, do not include information about color or design
 If appropriate, include information about shape and relative
size
 If the image includes data in the form of a chart or graph,
present that data in a data table
— ensure that proper markup is used (e.g., <th> on header
cells; @scope if necessary)
 Include the text of the photo caption if the text is contained
within the image (as opposed to being provided as true text)
Question 2: complex image
Question 2: complex image
The ribbon model resembles a tangle of string, connected in a
few places with yellow lines. One section is indented and
labeled “groove.”
The space-filling model is a grape-like cluster of grey spheres.
Some of the spheres are half red or half blue. One section is
indented and labeled “groove.”
Question 3: complex image
 How would
you describe
the following
image?
Question 3: complex image
 Summarize the illustration briefly
 If color or design are used to provide information, include this
in the description; otherwise do not include these elements in
the description
 Provide a description based on the intent of the image as well
as the intended audience
Question 3: complex image
 Complex illustrations can usually be broken down into data
tables or lists
— this illustration can be viewed as a flow chart
— follow the logical flow of the illustration
— use nested lists as a way to help organize information or
data progression
Question 3: complex image
An illustration shows tissues, cells and blood plasma separated
by interstitial fluid. Arrows of various thicknesses show CO2
moving from the tissue cells into the interstitial fluid and then into
the blood plasma. The reactions are listed.
— A medium arrow shows CO2 moving from the interstitial fluid into the
plasma, then it is dissolved in plasma.
— Narrow arrow shows CO2 moving from the interstitial fluid into the
plasma with the reaction, CO2 + H2O slow yields H2CO3 yields HCO3
negative + H positive which binds to plasma proteins.
— …and so on.
Question 4: complex flow chart
 What
approach
would you
take with
the following
image?
Question 4: complex flow chart
 Look at the context. Does the surrounding text cover this material with the
visual as a backup? If so refer to the text.
 Use common abbreviations if they make sense; check text for usage.
 This image is essentially a complex flow chart with multiple interactions at
each step.
 Begin with a brief overview that explains any distinctive visual elements
(major sections and branching points, for example)
 Provide a list that follows the numbered progression shown in the image
— use nested lists as a way to help organize information or data
progression
 Do not describe visual attributes (e.g., colors, shapes) unless there is an
explicit need to do so.
Question 4: complex flow chart
A diagram shows steps in a process. The diagram has four main sections: Wireless Client;
Wireless Access Point (WAP); Network Authentication and Authorization Service (NAAS); and
Network Resources. Each main section is divided into subsections.
Step 1: Certificate Enrollment: connects the Wireless Client’s Certificate Client to the NAAS’s
Certificate Authority, which is linked by a Certificate to a User in the Directory.
Step 2: Client Authentication: the Wireless Client’s Certificate Client passes a Certificate
through a TLS tunnel past the WAP’s Authentication and Key Management and into the NAAS’s
RADIUS (Network Authentication and Access Control). The RADIUS also gets input from the
User in the Directory.
Step 3: Authorization: with input from the NAAS’s Access Policy, the RADIUS provides
authorization to the WAP’s Authentication and Key Management.
Step 4: Key agreement: from Authentication and Key Management in the WAP to three places:
— Within the WAP, to the Crypto Module within the WLAN Bridge.
— To the WLAN Client section of the Wireless Client, and onto the Crypto Module of the
Wireless Client.
— To the RADIUS within the NAAS.
…and so on
Question 5: timeline
 How would you
describe this
graph?
Question 5: timeline
 These are two timelines, which are essentially line graphs
 Begin with a brief overview that conveys the timespan and
topic
— provide title and axis information
 Convert the data in each timeline into a data table OR a list,
as appropriate.
 Do not describe visual attributes (e.g., colors, shapes) unless
there is an explicit need to do so
Question 5: timeline
Figure 19.2, World Population Growth: 10,000 B.P. – 2000 A.D. Two graphs. In the first graph,
the horizontal axis measures years before present and the vertical axis measures estimated
population in billions. From 10,000 years ago the population is very small and gradually rises to
half a billion, until just before present when it suddenly shoots up to five billion. The second
graph shows details of the last 500 years. Events are marked on both graphs. For the first graph,
the events are listed below as a timeline.
10,000 years before present, population just above zero.
Ice age ends.
8,000 years before present.
Early humans in Patagonia.
Pyramids, approximately 4,500 years before present.
Confucius, approximately 2,500 years before present.
Christ, 2,000 years before present.
Fall of Rome.
Mohammed.
Crusades.
…and so on
Question 6: guidelines
 Where can I find a basic list for teachers to reference how to
create accessible images?
— for sciences, social science, arts, math
 Are there guidelines or recommendations on how to write the
descriptions for graphics?
 Are there stock or standard descriptions for mathematical
items such as coordinate planes, line plots, stem-and-leaf,
etc.?
 How to describe items such as political cartoons,
photographs, paintings, etc.?
Question 6: guidelines
 Effective Practices for Description of Science Content within
Digital Talking Books
 HTML5: Techniques for Providing Useful Text Alternatives
 WebAIM’s Creating Accessible Images
 DIAGRAM Center
— Webinars archive
 sessions about image descriptions as well as accessible math
— POET
 tool for describing images in DAISY books (EPUB 3 support coming soon)
 American Printing House for the Blind (APH)
— APH Tactile Graphic Image Library
Question 6: guidelines
 Math and MathML
—
—
—
—
MathML 3.0
MathSpeak Initiative at gh
What are the Technology Issues Involved in Making Math Accessible?
DIAGRAM Webinar: Tools for Creating Accessible Math
 Guidelines for Accessible Assessments Project (GAAP) (draft)
— methods for describing math and ELA in assessments
 math guidelines include symbols, numbers, charts/graphs, expressions,
plots, etc.
 ELA guidelines include information about maps, cartoons, timelines, etc.
Question 6: artwork
Contact information
 DIAGRAM Center
Julie Noblitt
julien@benetech.org
http://diagramcenter.org
DIAGRAM is funded by the U.S. Department of Education, Office of
Special Education Programs (OSEP)
 NCAM
Geoff Freed, Bryan Gould
National Center for Accessible at the WGBH Educational Foundation
geoff_freed@wgbh.org; bryan_gould@wgbh.org
http://ncam.wgbh.org