Customizable Closed Captioning allows users to tailor the display of captions to their specific needs, improving readability and the overall user experience. All modern Closed Captioning must meet or exceed Enhanced Closed Captioning (ECC), specified in CEA 708-E, and allow users to customize the appearance of Closed Captioning.
1.1.2-A
Caption customization interfaces must provide a real-time preview of adjustments so users can immediately assess the changes without leaving the interface.
1.1.2-B
Customization options must include multiple levels of transparency for caption text, background, and window objects, allowing users to adjust captions based on their visual preferences and the content being displayed.
1.1.2-C
Platforms must provide a minimum of 22 color choices for text, background, and window objects, as outlined in CEA 708-E. These color options ensure that captions remain visible and clear in a wide variety of viewing conditions, accommodating users with different types of color blindness.
- Black – cea(0, 0, 0), rgb(0, 0, 0), #000000
- Gray – cea(1, 1, 1), rgb(85, 85, 85), #555555
- White – cea(2, 2, 2), rgb(170, 170, 170), #AAAAA – this is light gray
- Bright White – cea(3, 3, 3), rgb(255, 255, 255), #FFFFFF – this is white
- Dark Red – cea(1, 0, 0), rgb(85, 0, 0), #550000
- Red – cea(2, 0, 0), rgb(170, 0, 0), #AA0000
- Bright Red – cea(3, 0, 0), rgb(255, 0, 0), #FF0000
- Dark Green – cea(0, 1, 0), rgb(0, 85, 0), #005500
- Green – cea(0, 2, 0), rgb(0, 170, 0), #00AA00
- Bright Green – cea(0, 3, 0), rgb(0, 255, 0), #00FF00
- Dark Blue – cea(0, 0, 1), rgb(0, 0, 85), #000055
- Blue – cea(0, 0, 2), rgb(0, 0, 170), #0000AA
- Bright Blue – cea(0, 0, 3), rgb(0, 0, 255), #0000FF
- Dark Yellow – cea(1, 1, 0), rgb(85, 85, 0), #555500
- Yellow – cea(2, 2, 0), rgb(170, 170, 0), #AAAA00
- Bright Yellow – cea(3, 3, 0), rgb(255, 255, 0), #FFFF00
- Dark Magenta – cea(1, 0, 1), rgb(85, 0, 85), #550055
- Magenta – cea(2, 0, 2), rgb(170, 0, 170), #AA00AA
- Bright Magenta – cea(3, 0, 3), rgb(255, 0, 255), #FF00FF
- Dark Cyan – cea(0, 1, 1), rgb(0, 85, 85), #005555
- Cyan – cea(0, 2, 2), rgb(0, 170, 170), #00AAAA
- Bright Cyan – cea(0, 3, 3), rgb(0,255,255), #00FFFF
1.1.2-D
Closed Captioning options must have an adjustable text size between 50-200%, allowing users to comfortably read captions from various distances or devices.
1.1.2-E
Closed Caption text sizing must be calculated via a 16:9 display (720p/HD, 1080p/FHD, 2160p/4K UHD, 4320p/8K UHD). Closed captioning characters exist in a grid with 15 horizontal rows and 42 vertical columns, after calculating 5% padding from all edges of the screen. This is the latest iteration of the Safe Title Area as defined by RP 2046-2. Simply, this is 90% of the pixel-based height and width of the screen divided by 15 and 42 respectively. A 100% text size character must fit into a single cell of that grid. 50% would utilize 30 rows and 84 columns, whereas 200% is rounded down to 7 rows and 21 columns. When calculated as pixels, the minimum font sizes for the 10-foot experience (or 50% of the standard) are – 720p:21px, 1080p:32px, 2160p:64px, 4320p:128px. The standard, or default, font sizes (100%) are – 720p:42px, 1080p:64px, 2160p:128px, 4320p:256px.
1.1.2-F
Captions should not exceed four lines of text at once. This prevents overwhelming the viewer with excessive information and supports cognitive accessibility. Prerecorded assets with properly synchronized captions wouldn’t typically approach this limitation as four lines of CC represents an extreme amount of information. Live, transcribed captions that use the roll-up presentation style typically use all four lines and expire older captions as new content is added.
1.1.2-G
Closed Captioning options must have at least one font choice for each of the following styles: default (set by CC provider), monospaced with serifs (i.e. Courier), proportionally spaced with serifs (i.e. Times New Roman), monospaced without serifs (i.e. Helvetica Monospaced), proportionally spaced without serifs (i.e. Arial), casual (i.e. Impress), cursive (i.e. Coronet), small capitals (i.e. Engravers Gothic), and readability (i.e. Lexend – the readability-focused font used on the videoa11y.org website).
1.1.2-H
Custom fonts used for Closed Captioning (excluding monospaced) must use a minimum letter spacing (kerning) of 10% relative to the font size. Letter spacing is crucial for readability but varies by font, which is why a recommended font is the better choice.
1.1.2-I
Platforms, apps, and websites that support Variable Font Technology (VFT) must use VFT fonts for Closed Captioning and include options to control the width, weight, and letter spacing for each font; additional customizations are optional. While VFT enhances readability and comprehension for everyone, it is not ubiquitously supported.
1.1.2-J
All fonts that satisfy Enhanced Closed Captioning style requirements must also have special character (unicode) support to properly display all supported characters in curated Closed Captioning content. (more information at Cornell)
1.1.2-K
Closed Captioning options must have at least one font edge style for each of the following choices: no edge (no style), raised edges (up bevel/emboss style), depressed edges (down bevel/emboss style), uniform edges (stroke/outline style), and drop shadowed (shadow angle unspecified) edges. Additional edge style considerations include inner shadow and inner/outer glow.
1.1.2-L
Closed Captioning options should respect the default text presentation style (pop-on, roll-up, and paint-on) as set by the CC providers unless the user has chosen to override the text presentation style by selecting another option including, but not limited to, pop-on, roll-up, and paint-on. Additional presentation styles should not violate accessibility guidelines surrounding animations found in section 2.1.1.
1.1.2-M
Closed Captioning options should respect the default positioning as set by the CC providers unless the user has chosen to override the positioning by selecting another position including, but not limited to, the horizontal positions (left, right, and center), the vertical positions (top, bottom, or middle), or any viable combination.
1.1.2-N
The Closed Captioning options interface must have at least 5 user-customizable presets or the ability to add presets at will. These presets must make the customizations persistent, even if the device is turned off, the user exits and re-enters an app, or the user logs out, etc., until they change to another preset or apply the default settings. An additional option must always allow the user to enable the default Closed Captioning options, removing all customizations and rendering captions as intended by the CC provider.