34 if (
_buffer.rbegin()->first < timestamp)
return _buffer.rbegin()->second;
35 if (
_buffer.begin()->first > timestamp)
return _buffer.begin()->second;
37 Buffer::const_iterator ub =
_buffer.upper_bound(timestamp);
38 Buffer::const_iterator lb = ub;
40 if (fabs(lb->first - timestamp) < fabs(ub->first - timestamp))