:) Solved....
InkCollector ic = new InkCollector();
Stream s = File.OpenRead(@"C:\Users\indhukanth\Desktop\krish\123.isf");
Ink loadedInk = new Ink();
byte[] isfBytes = new byte[s.Length];
s.Read(isfBytes, 0, (int)s.Length);
loadedInk.Load(isfBytes);
ic.Ink = loadedInk;
ExtendedProperties inkProperties = ic.Ink.ExtendedProperties;
byte[] fortifiedGif = null;
string nameBase = @"C:\Users\indhukanth\Desktop\krish\";
using (FileStream gifFile = File.OpenWrite(nameBase + "jib.gif"))
{
fortifiedGif = ic.Ink.Save(PersistenceFormat.Gif);
gifFile.Write(fortifiedGif, 0, fortifiedGif.Length);
}