AV_CH_LAYOUT_5POINT1_BACK

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_5POINT1_BACK = (AV_CH_LAYOUT_5POINT0_BACK | AV_CH_LOW_FREQUENCY);

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