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.
extern (C) @nogc nothrow
enum AV_CH_LAYOUT_7POINT1 = AV_CH_LAYOUT_5POINT1 | AV_CH_BACK_LEFT | AV_CH_BACK_RIGHT;

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