DefinitivePDF.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;

namespace Test.Utils
{
    public static class DefinitivePDF
    {
        public static Stream FromFile(string file)
        {
            var enc = Encoding.GetEncoding("latin1");

            var text = File.ReadAllText(file, enc);
            text = Regex.Replace(text, "/CreationDate\\([^\\)]+\\)", "/CreationDate(D:20000101000000+00'00')");
            text = Regex.Replace(text, "/ModDate\\([^\\)]+\\)", "/ModDate(D:20000101000000+00'00')");
            text = Regex.Replace(text, "/ID\\s+\\[<[^\\>]+><[^\\>]+>\\]", "/ID [<123><456>]");

            return new MemoryStream(enc.GetBytes(text));
        }
    }
}