Samsung PN51F4500AFXZA E-Manual page 37

Background Co,or: You can change the background color of the caption.
Options include Default, White, Black, Red, Green, Blue, Yellow, Magenta,
and Cyan.
Font Opacity: This adjusts the opacity of text.
Transparent, Translucent, Solid, and Flashing.
Options include Default
Background Opacity: This adjusts the opacity of the caption background,
Options include Default, Transparent, Translucent, Solid, and Flashing,
IRetum to IDefau_t: This option sets Size, Font Style, Foreground Color,
Background Color, Foreground Opacity, and Background Opacity to their
defaults.
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