static ColourConversion const & p3_to_xyz ();
static ColourConversion const & rec1886_to_xyz ();
static ColourConversion const & rec2020_to_xyz ();
static ColourConversion const & p3_to_xyz ();
static ColourConversion const & rec1886_to_xyz ();
static ColourConversion const & rec2020_to_xyz ();