convert jpg to pdf by c#

jpg2pdf.cs

void ConvertJPG2PDF(string jpgfile, string pdf)
{
	var document = new Document(iTextSharp.text.PageSize.A4, 25, 25, 25, 25);
	using (var stream = new FileStream(pdf, FileMode.Create, FileAccess.Write, FileShare.None))
	{
		PdfWriter.GetInstance(document, stream);
		document.Open();
		using (var imageStream = new FileStream(jpgfile, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
		{
			var image = Image.GetInstance(imageStream);
			if (image.Height > iTextSharp.text.PageSize.A4.Height - 25)
			{
				image.ScaleToFit(iTextSharp.text.PageSize.A4.Width - 25, iTextSharp.text.PageSize.A4.Height - 25);
			}
			else if (image.Width > iTextSharp.text.PageSize.A4.Width - 25)
			{
				image.ScaleToFit(iTextSharp.text.PageSize.A4.Width - 25, iTextSharp.text.PageSize.A4.Height - 25);
			}
			image.Alignment = iTextSharp.text.Image.ALIGN_MIDDLE;
			document.Add(image);
		}

		document.Close();
	}
}

void ConvertJPG2PDF(string jpgfile, string pdf,string text)
        {
            var document = new Document(iTextSharp.text.PageSize.A4, 25, 25, 25, 25);
            PdfWriter pdfWriter;
            using (var stream = new FileStream(pdf, FileMode.Create, FileAccess.Write, FileShare.None))
            {
                //QR Code

                pdfWriter = PdfWriter.GetInstance(document, stream);
                document.Open();
                iTextSharp.text.Image image;
                using (var imageStream = new FileStream(jpgfile, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
                {
                    image = iTextSharp.text.Image.GetInstance(imageStream);
                    if (image.Height > iTextSharp.text.PageSize.A4.Height - 25)
                    {
                        image.ScaleToFit(iTextSharp.text.PageSize.A4.Width - 25, iTextSharp.text.PageSize.A4.Height - 25);
                    }
                    else if (image.Width > iTextSharp.text.PageSize.A4.Width - 25)
                    {
                        image.ScaleToFit(iTextSharp.text.PageSize.A4.Width - 25, iTextSharp.text.PageSize.A4.Height - 25);
                    }
                    image.Alignment = iTextSharp.text.Image.ALIGN_MIDDLE;
                    document.Add(image);
                    
                }

                //Adding text
                var textY = ((PageSize.A4.Height - image.ScaledHeight) / 2) - 5;
                var textX = PageSize.A4.Width / 2;
                var chunk = new Chunk(text, FontFactory.GetFont("Helvetica", 22.0f, BaseColor.BLACK));
                PdfContentByte cb = pdfWriter.DirectContent;
                cb.BeginText();
                ColumnText.ShowTextAligned(cb, Element.ALIGN_CENTER, new Phrase(chunk), textX, textY, 0);
                cb.EndText();

                document.Close();
            }
        }