Non-text Content:
Understanding SC 1.1.1
[begin change][end change]1.1.1 Non-text Content: All non-text content has a text alternative that presents equivalent information, except for the situations listed below. [1992] (Level A)
Controls, Input: If [begin add]it[end add] [begin delete]non-text content[end delete] is a control or accepts user input, then it has a name that describes its purpose. (See also Guideline 4.1.)
Media, Test, Sensory: If [begin add]it[end add] [begin delete]non-text content[end delete] is [begin delete]any of the following[end delete] [begin add](1) [end add] synchronized media, [begin add](2) [end add] live audio-only or live video-only content, [begin add](3) [end add]a test or exercise that must be presented in non-text format, [begin add](4) [end add] [begin delete]content [end delete]primarily intended to create a specific sensory experience, then text alternatives at least [begin change]provide descriptive identification of the non-text content[end change] [begin add], or (5) a media alternative to text that is clearly labeled as such [2290] [end add]. (For synchronized media, see also Guideline 1.2.)
[end change]Note: Prerecorded audio-only and video-only files would be covered under Success Criterion 1.1.1, which requires text alternatives that present equivalent information.
[2082]CAPTCHA: If [begin add]it[end add] [begin delete]the purpose of non-text content[end delete] is to confirm that content is being accessed by a person rather than a computer, then text alternatives that identify and describe the purpose of the non-text content are provided[begin add], and alternative forms of CAPTCHA using output modes for different types of sensory perception[end add] [begin delete]and alternative forms in different modalities[end delete] are provided to accommodate different disabilities.
Decoration, Formatting, Invisible: If [begin add]it[end add] [begin delete]non-text content[end delete] is pure decoration, or used only for visual formatting, or if it is not presented to users, then it is implemented [begin change]in a way[end change] [begin delete]such[end delete] that it can be ignored by assistive technology.
Intent of this Success Criterion
The intent of this success criterion is to make information conveyed by non-text content accessible through the use of a text alternative. Text alternatives are a primary way for making information accessible because they can be rendered through any sensory modality (for example, visual, auditory or tactile) to match the needs of the user. Providing text alternatives allows the information to be rendered in a variety of ways by a variety of user agents. For example, a person who cannot see a picture can have the text alternative read aloud using synthesized speech. A person who cannot hear an audio file can have the text alternative displayed so that he or she can read it. In the future, text alternatives will also allow information to be more easily translated into sign language or into a simpler form of the same language.
Note on CAPTCHA
CAPTCHAs are a controversial topic in the accessibility community. As is described in the paper Inaccessibility of CAPTCHA, CAPTCHAs intrinsically push the edges of human abilities in an attempt to defeat automated processes. Every type of CAPTCHA will be unsolvable by users with certain particular disabilities. However, they are widely used, and the Web Content Accessibility Guidelines Working Group believes that if CAPTCHAs were forbidden outright, Web sites would choose not to conform to WCAG rather than abandon CAPTCHA. This would create barriers for a great many more users with disabilities. For this reason the Working Group has chosen to structure the requirement about CAPTCHA in a way that meets the needs of most people with disabilities, yet is also considered adoptable by sites. Requiring two different forms of CAPTCHA on a given site ensures that most people with disabilities will find a form they can use.
Because some users with disabilities will still not be able to access sites that meet the minimum requirements, the Working Group provides recommendations for additional steps. Organizations motivated to conform to WCAG should be aware of the importance of this topic and should go as far beyond the minimum requirements of the guidelines as possible. Additional recommended steps include:
Providing more than two modalities of CAPTCHAs
Providing access to a human customer service representative who can bypass CAPTCHA
Not requiring CAPTCHAs for authorized users
Additional information
Non-text content can take a number of forms, and this success criterion specifies how each is to be handled.
For non-text content that is not covered by one of the other situations listed below, such as charts, diagrams, audio recordings, pictures, and animations, text alternatives can make the same information available in a form that can be rendered through any modality (for example, visual, auditory or tactile). Short and long text alternatives can be used as needed to convey the information in the non-text content. Note that prerecorded audio-only and prerecorded video-only files are covered here. Live-audio-only and Live-video-only files are covered below (see 3rd paragraph following this one).
For non-text content that is a control or accepts user input , such as images used as submit buttons or complex animations, a name is provided to describe the purpose of the non-text content so that the person at least knows what the non-text content is and why it is there.
Non-text content that is synchronized media is made accessible through guideline 1.2. However it is important that users know what it is when they encounter it on a page so they can decide what action if any they want to take with it. A text alternative that describes the synchronized media and/or gives its title is therefore provided.
Live Audio-only and live video-only files - It is much more difficult to provide text alternatives that convey the same information as live audio-only and live video-only content. For these types of non-text content, text alternatives provide a descriptive label.
Sometimes a test or exercise must use a particular sense. Audio or visual information is provided that cannot be changed to text because the test or exercise must be conducted using that sense. For example, a hearing test would be invalid if a text alternative were provided. A visual skill development exercise would similarly make no sense in text form. And a spelling test with text alternatives would not be very effective. For these cases, text alternatives should be provided to describe the purpose of the non-text content; of course, the text alternatives would not provide the same information needed to pass the test.
Sometimes content is primarily intended to create a specific sensory experience that words cannot fully capture. Examples include a symphony performance, works of visual art etc. For such content, text alternatives at least identify the non-text content with a descriptive label and where possible, some descriptive text. If the reason for including the content in the page is known and can be described it is helpful to include that information.
Sometimes there are non-text exercises that are used to prove you are human. To avoid spam robots and other software from gaining access to a site a device called a CAPTCHA is used. These usually involve visual or auditory tasks that are beyond the current capabilities of web robots. Providing a text alternative to them would however make them operable by Robots, thus defeating their purpose. In this case a text alternative would describe the purpose of the CAPTCHA, and alternate forms using different modalities would be provided to address the needs of people with different disabilities.
Sometimes there is non-text content that really is not meant to be seen or understood by the user. Transparent images used to move text over on a page; a one pixel transparent "web-bug" that tells the author when the page is viewed; and a swirl in the corner that conveys no information but just fills up a blank space to create an aesthetic effect are all examples of this. Putting alternative text on such items just distracts people using screen readers from the content on the page. Not marking the content in any way, though, leaves users guessing what the non-text content is and what information they may have missed (even though they have not missed anything in reality). This type of non-text content, therefore, is marked or implemented in a way that assistive technologies (AT) will ignore it and not present anything to the user.
Specific Benefits of Success Criterion 1.1.1:
This success criterion helps people who have difficulty perceiving visual content. Assistive technology can read text alternatives aloud, present them visually, or convert them to braille.
Text alternatives may help some people who have difficulty understanding the meaning of photographs, drawings, and other images (e.g. line drawings, graphic designs, paintings, three-dimensional representations), graphs, charts, animations, etc.
People who are deaf, are hard of hearing, or who are having trouble understanding audio information for any reason can read the text presentation. Research is ongoing regarding automatic translation of text into sign language.
People who are deaf-blind can read the text in braille.
Additionally, text alternatives support the ability to search for non-text content and to repurpose content in a variety of ways.
Examples of Success Criterion 1.1.1
A data chart
A bar chart compares how many widgets were sold in June, July, and August. The short label says, "Figure one - Sales in June, July and August." The longer description identifies the type of chart, provides a high-level summary of the data, trends and implications comparable to those available from the chart. Where possible and practical, the actual data is provided in a table.
An audio recording of a speech (no video)
The link to an audio clip says, "Chairman's speech to the assembly." A link to a text transcript is provided immediately after the link to the audio clip.
An animation that illustrates how a car engine works
An animation shows how a car engine works. There is no audio and the animation is part of a tutorial that describes how an engine works. Since the text of the tutorial already provides a full explanation, the text alternative has a brief description of the image and refers to the tutorial text for more information.
A traffic Web camera
A Web site allows users to select from a variety of Web cameras positioned throughout a major city. After a camera is selected, the image updates every two minutes. A short text alternative identifies the Web camera as "traffic Web camera." The site also provides a table of travel times for each of the routes covered by the Web cameras. The table is also updated every two minutes.
A photograph of an historic event in a news story
A photograph of two world leaders shaking hands accompanies a news story about an international summit meeting. The text alternative says, "President X of Country X shakes hands with Prime Minister Y of country Y."
A photograph of a historic event in content discussing diplomatic relationships
The same image is used in a different context intended to explain nuances in diplomatic encounters. The image of the president shaking hands with the prime minister appears on a Web site discussing intricate diplomatic relationships. The first text alternative reads, "President X of country X shakes hands with Prime Minister Y of country Y on January 2, 2009." An additional text alternative describes the room where the leaders are standing as well as the expressions on the leaders' faces, and identifies the other people in the room. The additional description might be included on the same page as the photograph or in a separate file associated with the image through a link or other standard programmatic mechanism.
An audio recording
The Web page described in the previous example includes a link to an audio recording of the leaders' press conference. The page also links to a text transcript of the press conference. The transcript includes a verbatim record of everything the speakers say. It identifies who is speaking as well as noting other significant sounds that are part of the recording, such as applause, laughter, questions from the audience, and so on.
An e-learning application
An e-learning application uses sound effects to indicate whether or not the answers are correct. The chime sound indicates that the answer is correct and the beep sound indicates that the answer is incorrect. A text description is also included so that people who can't hear or understand the sound understand whether the answer is correct or incorrect.
A linked thumbnail image
A thumbnail image of the front page of a newspaper links to the home page of the "Smallville Times". The text alternative says "Smallville Times".
- [begin add]
Different alternatives for an image of the world: An image of the world that is used on a travel site as a link to the International Travel section has the text alternative "International Travel". The same image is used as a link on a university Web site with the text alternative "International Campuses". [2331]
[end add]
Related Resources
Resources are for information purposes only, no endorsement implied.
Excerpts from the NBA Tape Recording Manual, Third Edition. Information on describing complex images to people who are blind.
Inaccessibility of CAPTCHA. Examines a number of potential solutions that allow systems to test for human users while preserving access by users with disabilities.
Techniques and Failures for Success Criterion 1.1.1 [Non-text Content]
Each numbered item in this section represents a technique or combination of techniques that the WCAG Working Group deems sufficient for meeting this success criterion. The techniques listed only satisfy the success criterion if all of the WCAG 2.0 conformance requirements have been met.
Sufficient Techniques
Instructions: Select the situation below that matches your content. Each situation includes numbered techniques (or combinations of techniques) that the Working Group deems to be sufficient for that situation.
Situation A: If a short description can serve the same purpose and present the same information as the non-text content:
G94: Providing short text alternative for non-text content that serves the same purpose and presents the same information as the non-text content using a short text alternative technique listed below
Situation B: If a short description can not serve the same purpose and present the same information as the non-text content (e.g. a chart or diagram):
G95: Providing short text alternatives that provide a brief description of the non-text content using a short text alternative technique listed below AND one of the following techniques for long description:
G92: Providing long description for non-text content that serves the same purpose and presents the same information using a long text alternative technique listed below
Situation C: If non-text content is a control or accepts user input:
G82: Providing a text alternative that identifies the purpose of the non-text content using a short text alternative technique listed below
Using HTML form controls and links (future link)
H44: Using label elements to associate text labels with form controls (HTML)
H65: Using the title attribute to identify form controls when the label element cannot be used (HTML)
Using (X)HTML according to spec (future link)
Situation D: If non-text content is synchronized media; live audio-only or live video-only content; a test or exercise that must use a particular sense; or primarily intended to create a specific sensory experience:
Providing a descriptive label using a short text alternative technique listed below
G68: Providing a descriptive label that describes the purpose of live audio-only and live video-only content using a short text alternative technique listed below
G100: Providing the accepted name or a descriptive name of the non-text content using a short text alternative technique listed below
Situation F: If the non-text content should be ignored by assistive technology:
Implementing or marking the non-text content so that it will be ignored by assistive technology using one of the technology-specific techniques listed below
[begin change] Short text alternative techniques for use in sufficient techniques above[end change]
H36: Using alt attributes on images used as submit buttons (HTML)
H24: Providing text alternatives for the area elements of image maps (HTML)
Providing text alternatives for strings where look-alike glyphs are used in place of letters (e.g. leetspeak) (future link)
Providing text alternatives for ASCII art (future link)
[begin change] Long text alternative techniques for use in sufficient techniques above[end change]
H45: Using longdesc (HTML)
Additional Techniques (Advisory)
Although not required for conformance, the following additional techniques should be considered in order to make content more accessible. Not all techniques can be used or would be effective in all situations.
General Techniques for Informative Non-Text Content (Advisory)
Identifying informative non-text content (future link)
Keeping short descriptions short (future link)
Describing images that include text (future link)
Providing a longer description of the non-text content where only a descriptive label is required using a technology-specific technique (for an accessibility-supported content technology) for long description listed above (future link)
- [begin add]
Providing different sizes for non-text content when it cannot have an equivalent accessible alternative (future link) [2269]
[end add]
General Techniques for Live Non-Text Content (Advisory)
Linking to textual information that provides comparable information (e.g. for a traffic Webcam, a municipality could provide a link to the text traffic report.) (future link)
Providing a transcript of a live audio only presentation after the fact (future link)
General techniques to minimize the barrier of CAPTCHAs
Providing more than two modalities of CAPTCHAs (future link)
Providing access to a human customer service representative who can bypass CAPTCHA (future link)
Not requiring CAPTCHAs for authorized users (future link)
HTML Techniques (Advisory)
Writing for browsers that do not support frame
Providing alternative content for iframe
H27: Providing text and non-text alternatives for object (HTML)
Not using long descriptions for iframe
Providing redundant text links for client-side image maps (future link)
CSS Techniques (Advisory)
Using CSS margin and padding rules instead of spacer images (future link)
Using CSS background, :before or :after rules for decorative images instead of img elements (future link)
Displaying empty table cells (future link)
ARIA Techniques (Advisory)
- [begin add]
Using the ARIA presentation role to indicate elements are purely presentational (future link) [1977]
[end add]
Metadata techniques (Advisory)
Using metadata to associate text transcriptions with a video (future link)
Using metadata to associate text transcriptions with audio-only content (future link)
EXAMPLE: Providing, in metadata, URL(s) that points to an audio description and a text transcript of a video.
EXAMPLE: Providing, in metadata, URL(s) that point to several text transcripts (English, French, Dutch) of an audio file.
Failures
The following are common mistakes that are considered failures of Success Criterion 1.1.1 by the WCAG Working Group.
Key Terms
- assistive technology (as used in this document)
- [begin add]
hardware and/or software that acts as a user agent, or along with a mainstream user agent, to provide [begin change]functionality[end change] to meet the requirements of users with disabilities that go beyond those offered by [begin delete]the [end delete]mainstream user agents [2140]
[end add][begin delete]provides services to meet the requirements of users with disabilities that go beyond those offered by the mainstream user agents. Such services include alternative presentations (e.g., as synthesized speech or magnified content), alternative input methods (e.g., voice), additional navigation or orientation mechanisms, and content transformations (e.g., to make tables more accessible), and
[begin change]may rely[end change] [begin delete]usually relies[end delete] on services (such as retrieving Web content and parsing markup) provided by one or more other mainstream user agents. Assistive technologies communicate data and messages with mainstream user agents by using and monitoring APIs
[begin add]Note 1: [begin change]functionality[end change] provided by assistive technology includes alternative presentations (e.g., as synthesized speech or magnified content), alternative input methods (e.g., voice), additional navigation or orientation mechanisms, and content transformations (e.g., to make tables more accessible). [2140] [2270]
[end add][begin add]Note 2: Assistive technologies often communicate data and messages with mainstream user agents by using and monitoring APIs. [2270]
[end add][begin add]Note 3: The distinction between mainstream user agents and assistive technologies is not absolute. Many mainstream user agents provide some features to assist individuals with disabilities. The basic difference is that mainstream user agents target broad and diverse audiences that usually include people with and without disabilities. Assistive technologies target narrowly defined populations of users with specific disabilities. The assistance provided by an assistive technology is more specific and appropriate to the needs of its target users. The mainstream user agent may provide important [begin change]functionality[end change] to assistive technologies like retrieving Web content from program objects or parsing markup into identifiable bundles. [2171]
[end add][begin delete]Note 4: In this definition, user agents are user agents in the general sense of the term. That is, any software that retrieves and presents Web content for users. The mainstream user agent may provide important services to assistive technologies like retrieving Web content from program objects or parsing markup into identifiable bundles.
[end delete][begin delete]Note 5: Mainstream user agents may also provide services directly that meet the requirements of users with disabilities.
[end delete][begin delete]Note 6: This definition is based on User Agent Accessibility Guidelines 1.0 Glossary.
[end delete]Example: Examples of assistive technologies that are important in the context of this document include the following:
screen magnifiers, and other visual reading assistants, which are used by people with visual, perceptual and physical print disabilities to change text font, size, spacing, color, synchronization with speech, etc. in order to improve the visual readability of rendered text and images;
screen readers, which are used by people who are blind to read textual information through synthesized speech or braille;
text-to-speech software, which is used by some people with cognitive, language, and learning disabilities to convert text into synthetic speech;
voice recognition software, which may be used by people who have some physical disabilities;
alternative keyboards, which are used by people with certain physical disabilities to simulate the keyboard[begin add] (including alternate keyboards that use head pointers, single switches, sip/puff and other special input devices.)[end add];
alternative pointing devices, which are used by people with certain physical disabilities to simulate mouse pointing and button activations.
- CAPTCHA
initialism for "Completely Automated Public Turing test to tell Computers and Humans Apart"
Note 1: CAPTCHA tests often involve asking the user to type in text that is displayed in an obscured image or audio file.
Note 2: A Turing test is any system of tests designed to differentiate a human from a computer. It is named after famed computer scientist Alan Turing. The term was coined by researchers at Carnegie Mellon University. [CAPTCHA]
- live audio-only
a time-based live presentation that contains only audio (no video and no interaction)
- live video-only
a time-based live presentation that contains only video (no audio and no interaction)
- media alternative to text
media that presents no more information than is already presented in text (directly or via text alternatives) [2250] [2290]
Note: A media alternative to text is provided for those who benefit from alternate representations of text. Media alternatives to text may be audio-only, video-only (including sign-language video), or audio-video.
- must be presented in non-text format
would be invalid if presented in text
Example: Color blindness test, hearing test, vision exercise, spelling test.
- name
text by which software can identify a component within Web content to the user
Note 1: The name may be hidden and only exposed by assistive technology, whereas a label is presented to all users. In many (but not all) cases, the label and the name are the same.
Note 2: This is unrelated to the name attribute in HTML.
- non-text content
any content that is not a sequence of characters that can be programmatically determined or where the sequence is not expressing something in human language
- pure decoration
serving only an aesthetic purpose, providing no information, and having no functionality
Note: Text is only purely decorative if the words can be rearranged or substituted without changing their purpose.
Example: The cover page of a dictionary has random words in very light text in the background.
- specific sensory experience
a sensory experience that is not purely decorative and does not primarily convey important information or perform a function
Example: Examples include a performance of a flute solo, works of visual art etc.
- synchronized media
audio or video synchronized with another format for presenting information and/or with time-based interactive components
- text alternative
programmatically determined text that is used in place of non-text content, or text that is used in addition to non-text content and referred to from the programmatically determined text
Example: An image of a chart is described in text in the paragraph after the chart. The short text-alternative for the chart indicates that a description follows.