FF_LAYOUT2COUNT.FF_LAYOUT2COUNT

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
template FF_LAYOUT2COUNT(int l)
extern (C) @nogc nothrow
enum FF_LAYOUT2COUNT = (((l) & 0x8000000000000000) ? ((l) & 0x7FFFFFFF) : 0);

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