OfficeOpenXml.ExcelHeaderFooterText.InsertPicture C# (CSharp) Method

        public ExcelVmlDrawingPicture InsertPicture(FileInfo PictureFile, PictureAlignment Alignment)
        {
            string id = ValidateImage(Alignment);

            Image Picture;
            try
            {
                if (!PictureFile.Exists)
                {
                    throw (new FileNotFoundException(string.Format("{0} is missing", PictureFile.FullName)));
                }
                Picture = Image.FromFile(PictureFile.FullName);
            }
            catch (Exception ex)
            {
                throw (new InvalidDataException("File is not a supported image-file or is corrupt", ex));
            }

            ImageConverter ic = new ImageConverter();
            string contentType = ExcelPicture.GetContentType(PictureFile.Extension);
            var uriPic = XmlHelper.GetNewUri(_ws._package.Package, "/xl/media/"+PictureFile.Name.Substring(0, PictureFile.Name.Length-PictureFile.Extension.Length) + "{0}" + PictureFile.Extension);
            byte[] imgBytes = (byte[])ic.ConvertTo(Picture, typeof(byte[]));
            var ii = _ws.Workbook._package.AddImage(imgBytes, uriPic, contentType);

            return AddImage(Picture, id, ii);
        }