create bitmap with filestream

I need to create a bitmap with a filestream. So far I have this Code:

 using (FileStream bmp = File.Create(@"C:\test.bmp"))        {            BinaryWriter writer = new BinaryWriter(bmp);            int i = 0;          //  writer.Write((char*)&fileheader, sizeof(fileheader));          //  writer.Write((char*)&infoheader, sizeof(infoheader));            for (int rows = 0; rows < 160; rows++)            {                for (int cols = 0; cols < 112; cols++)                {                    writer.Write(CamData[i]);                    i++;                }            }            bmp.Close();        }

but I still need the header Informations for the bitmap. My Problem is, that I dont know how to implement they in C#. I know the resolution (320 x 240 ) and my pixeldata are 16 bit grayscale values given in a ushort array.

thanks