AVCaptionMediaSubTypeKey

Static AVCaptionMediaSubTypeKey 

Source
pub unsafe static AVCaptionMediaSubTypeKey: Option<&'static AVCaptionSettingsKey>
Available on crate feature AVCaptionSettings only.
Expand description

Indicates the output media subtype of a caption conversion operation. For example, [NSNumber numberWithInt:kCMClosedCaptionFormatType_CEA608].

Both numeric and string forms of media subtypes are accepted for caption conversions, so you could, for example, use “ c608“ instead of [NSNumber numberWithInt:kCMClosedCaptionFormatType_CEA608].

See also Apple’s documentation