Principle 1: Perceivable

1.0: Principle 1: Perceivable

Information and user interface components must be presentable to users in ways they can perceive.

1.1 : Text Alternatives

Provide text alternatives for any non-text content so that it can be changed into other forms people need, such as large print, braille, speech, symbols or simpler language

http://www.w3.org/TR/UNDERSTANDING-WCAG20/text-equiv.html

1.1.1: Non-text Content:(A)

All non-text content that is presented to the user has a text alternative that serves the equivalent purpose, except for the situations listed below. (Level A)

1.2 : Time-based Media:

Provide alternatives for time-based media

http://www.w3.org/TR/UNDERSTANDING-WCAG20/media-equiv.html

1.2.1: Audio-only and Video-only (Prerecorded): (A)

For prerecorded audio-only and prerecorded video-only media, the following are true, except when the audio or video is a media alternative for text and is clearly labeled as such: (Level A)

1.2.2: Captions (Prerecorded): (A)

Captions are provided for all prerecorded audio content in synchronized media, except when the media is a media alternative for text and is clearly labeled as such. (Level A)

1.2.3: Audio Description or Media Alternative (Prerecorded): (A)

An alternative for time-based media or audio description of the prerecorded video content is provided for synchronized media, except when the media is a
media alternative for text and is clearly labeled as such. (Level A)

1.2.4: Captions (Live): (AA)

Captions are provided for all live audio content in synchronized media. (Level AA)

Sufficient Techniques for 1.2.4 – Captions (Live)

  • 1.G9: Creating captions for live synchronized media AND G93: Providing open (always visible) captions

1.2.5: Audio Description (Prerecorded): (AA)

Audio description is provided for all prerecorded video content in synchronized media. (Level AA)

Sufficient Techniques for 1.2.5 – Audio Description (Prerecorded)

  • 1.G78: Providing a second, user-selectable, audio track that includes audio descriptions

1.2.6: Sign Language (Prerecorded): (AAA)

Sign language interpretation is provided for all prerecorded audio content in synchronized media. (Level AAA)

Sufficient Techniques for 1.2.6 – Sign Language (Prerecorded)

  • 1.G54: Including a sign language interpreter in the video stream

1.2.7: Extended Audio Description (Prerecorded): (AAA)

Where pauses in foreground audio are insufficient to allow audio descriptions to convey the sense of the video, extended audio description is provided for all prerecorded video content in synchronized media. (Level AAA)

1.2.8: Media Alternative (Prerecorded): (AAA)

An alternative for time-based media is provided for all prerecorded synchronized media and for all prerecorded video-only media. (Level AAA)

1.2.9: Audio-only (Live): (AAA)

An alternative for time-based media that presents equivalent information for live audio-only content is provided. (Level AAA)

1.3.0: Create content that can be presented in different ways (for example simpler layout ) without losing information or structure

http://www.w3.org/TR/UNDERSTANDING-WCAG20/content-structure-separation.html

1.3.1: Info and Relationships: (A)

Information, structure,and relationships conveyed through presentation can be programmatically determined or are available in text. (Level A

1.3.2: Meaningful Sequence: (A)

When the sequence in which content is presented affects its meaning, a correct reading sequence can be programmatically determined. (Level A)

1.3.3: Sensory Characteristics: (A)

Instructions provided for understanding and operating content do not rely solely on sensory characteristics of components such as shape, size, visual location,
orientation, or sound. (Level A)

1.4.0: Make it easier for users to see and hear content including separating foreground from background

Advisory Techniques for Guideline 1.4

  • Using readable fonts
  • Making sure any text in images of text is at least 14 points and has good contrast

1.4.1: Use of Color: (A)

Color is not used as the only visual means of conveying information, indicating an action, prompting a response, or distinguishing a visual element. (Level A)

1.4.2: Audio Control: (A)

If any audio on a Web page plays automatically for more than 3 seconds, either a mechanism is available to pause or stop the audio, or a mechanism is available to control audio volume independently from the overall system volume level. (Level A)

1.4.3: Contrast (Minimum): (AA)

The visual presentation of text and images of text has a contrast ratio of at least 4.5:1, except for the following: (Level AA)

1.4.4: Resize text: (AA)

Except forcaptions and images of text, text can be resized without assistive technology up to 200 percent without loss of content or functionality. (Level AA)

1.4.5: Images of Text: (AA)

If the technologies being used can achieve the visual presentation, text is used to convey information rather than images of text except for the following: (Level AA)

1.4.6: Contrast (Enhanced): (AAA)

The visual presentation of text and images of text has a contrast ratio of at least 7:1, except for the following: (Level AAA)

1.4.7: Low or No Background Audio: (AAA)

For prerecorded audio-only content that (1) contains primarily speech in the foreground, (2) is not an audio CAPTCHA or audio logo, and (3) is not vocalization intended to be primarily musical expression such as singing or rapping, at least one of the following is true: (Level AAA)

1.4.8: Visual Presentation: (AAA)

For the visual presentation of blocks of text, a mechanism is available to achieve the following: (Level AAA)

  • 1.foreground and background colors can be selected by the user

1.4.9: Images of Text (No Exception): (AAA)

Images of text are only used for pure decoration or where a particular presentation of text is essential to the information being conveyed. (Level AAA)