AV_CH_LAYOUT_7POINT0_FRONT

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_7POINT0_FRONT = AV_CH_LAYOUT_5POINT0 | AV_CH_FRONT_LEFT_OF_CENTER | AV_CH_FRONT_RIGHT_OF_CENTER;

Meta