mixster

 function QueryPerformanceFrequency(out Frequency: Int64): LongBool; external 'QueryPerformanceFrequency@kernel32.dll stdcall';
 function QueryPerformanceCounter(out Counter: Int64): LongBool; external 'QueryPerformanceCounter@kernel32.dll stdcall';

procedure MarkTime(var Time: Int64);
var
  Freq: Int64;
begin
  if QueryPerformanceFrequency(Freq) then
    QueryPerformanceCounter(Time)
  else
    Time := GetTickCount;
end;

function TimeFromMark(Mark: Int64): Double;
var
  Freq, Now: Int64;
begin
  if QueryPerformanceFrequency(Freq) then
  begin
    QueryPerformanceCounter(Now);
    Result := ((Now - Mark) / Freq) * 1000;
  end
  else
    Result := (GetTickCount - Mark);
end;