Change Captions preferences for accessibility on Mac
On your Mac, use the Captions pane of Accessibility preferences to control how subtitles are styled, and whether to use closed captions instead when they’re available. See Use subtitles and closed captions.
To change these preferences, choose Apple menu > System Preferences, click Accessibility , then click Captions.
Available built-in styles (Transparent Background, Classic, Large Text, Outline Text), and styles that you added.
To edit the settings for a style you added, select the style in the list, then click Edit.
Create a style.
Set background and text colours, and font settings. A new style inherits the settings of the style that’s selected when you click Add. If you like many of the settings of an existing style, select it before you click Add, then change just the settings you don’t like.
To have a setting always used, deselect its “Allow video to override” tickbox. In the bottom section, you can set the colour and size to use for a specific font whenever it’s used in subtitles. For example, set the font to use whenever Cursive is used in subtitles.
Delete a style that you added.
Prefer closed captions and SDH
If they’re available, use closed captions or SDH instead of standard subtitles for content played on your Mac.
Tip: The Outline Text style is especially useful for subtitles and captions that appear in Japanese.