image to pdf conversion without using third party library in C#

I have an urgent requirement in my project that i need to convert image files to PDF without using third party libraries in C#. The images can be in any format like (.jpg,.png,.jpeg,.tiff).

I am successfully able to do this with the help of itextsharp. here is the code.

string value = string.Empty;//value contains the data from a json file
    List<string> sampleData;
    public void convertdata()
    {
        //sampleData = Newtonsoft.Json.JsonConvert.DeserializeObject<List<string>>(value);
        var jsonD = System.IO.File.ReadAllLines(@"json.txt");
        sampleData = Newtonsoft.Json.JsonConvert.DeserializeObject<List<string>>(jsonD[0]);
        Document document = new Document();

        using (var stream = new FileStream("test111.pdf", FileMode.Create, FileAccess.Write, FileShare.None))
        {
            PdfWriter.GetInstance(document, stream);
            document.Open();

            foreach (var item in sampleData)
            {
                newdata = Convert.FromBase64String(item);
                var image = iTextSharp.text.Image.GetInstance(newdata);
                document.Add(image);
                Console.WriteLine("Conversion done check folder");

            }
            document.Close();
        }

But now i need to perform the same without using third party library.

I have searched the internet but i am unable to get something that can suggest a proper answer. All i am getting is to use it with either "itextsharp" or "PdfSharp" or with the "GhostScriptApi".

please suggest...??