Function vdef_transfer_function_from_str 

pub unsafe extern "C" fn vdef_transfer_function_from_str(
    str_: *const c_char,
) -> vdef_transfer_function

Get an enum vdef_transfer_function value from a string. Valid strings are only the suffix of the transfer function name (eg. ‘BT709’). The case is ignored. @param str: transfer function name to convert @return the enum vdef_transfer_function value or VDEF_TRANSFER_FUNCTION_UNKNOWN if unknown