AV_CH_LAYOUT_7POINT1

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
@nogc nothrow extern (C)
enum AV_CH_LAYOUT_7POINT1 = (AV_CH_LAYOUT_5POINT1 | AV_CH_BACK_LEFT | AV_CH_BACK_RIGHT);

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