IC.CoolWatermark.dll vs Graphics - perfomance speed

Hi,
i need to watermark on images.
i did it in two way.
first method,
using IC.CoolWatermark.dll
string WaterMarkText = "Comp Name"; // watermark text                           System.Drawing.Image bitmap = System.Drawing.Image.FromStream(stream); // got image from database                     IC.CoolWatermark.Writer writer = new Writer(bitmap);                     writer.PositionStyle = PositionStyle.MiddleCenter;                     writer.Shadow = new Shadow(Color.Transparent, 0, 0);    ...