C# utility function to convert an image to a PDF file using itextsharp.
public static void ConvertImageToPdf(string srcFilename, string dstFilename)
{
iTextSharp.text.Rectangle pageSize = null;
using (var srcImage = new Bitmap(srcFilename))
{
pageSize = new iTextSharp.text.Rectangle(0, 0, srcImage.Width, srcImage.Height);
}
using (var ms = new MemoryStream())
{
var document = new iTextSharp.text.Document(pageSize, 0, 0, 0, 0);
iTextSharp.text.pdf.PdfWriter.GetInstance(document, ms).SetFullCompression();
document.Open();
var image = iTextSharp.text.Image.GetInstance(srcFilename);
document.Add(image);
document.Close();
File.WriteAllBytes(dstFilename, ms.ToArray());
}
}