FFMPEG C# Scan for commercial breaks

        static List<TimeSpan> scanForCommercialBreaks(string file, double threshhold, double wait)
        {
            Process proc = new Process();
            proc.StartInfo.FileName = ffmpeg_location;

            string fname_noext = Path.GetFileNameWithoutExtension(file);
            string fname_root = Path.GetDirectoryName(file);

            string filename = file;

            //get duration
            proc.StartInfo.Arguments = "-i " + "\"" + filename + "\"" + " -vf blackframe -an -f null -";
            AddLog("scanForCommercialBreaks:" + proc.StartInfo.Arguments);
            //proc.StartInfo.Arguments = "-i " + "\"" + filename + "\"" + " -vf select='gte(scene,0)' -an -f null -";

            proc.StartInfo.RedirectStandardError = true;
            proc.StartInfo.UseShellExecute = false;
            if (!proc.Start())
            {
                Console.WriteLine("Error starting");
            }
            StreamReader reader = proc.StandardError;
            List<TimeSpan> nums = new List<TimeSpan>();
            string line;
            string last_num = "";
            Console.WriteLine("Scanning for Commercial Breaks...");
            DateTime now = DateTime.Now;
            while ((line = reader.ReadLine()) != null)
            {
                if((DateTime.Now - now) > TimeSpan.FromSeconds(.5))
                {
                    Console.Write("_");
                    now = DateTime.Now;
                }
                int a = line.IndexOf("Parsed_blackframe");
                //AddLog(line.ToString());
                if (a >= 0)
                {
                    a = line.IndexOf(" t:");
                    int b = line.IndexOf(" ", a + 1);
                    string num = line.Substring(a + 3, b - a - 3);
                    //Console.WriteLine("NUM:" + num);
                    if (last_num != "")
                    {
                        //
                        if (Double.Parse(num) - Double.Parse(last_num) > 2) nums.Add(TimeSpan.FromSeconds(0));
                    }
                    last_num = num;
                    if (Double.Parse(num) > wait)
                    {
                        nums.Add(TimeSpan.FromSeconds(Double.Parse(num)));
                        Console.Write(".");
                    }
                    else
                    {
                        Console.Write("<");
                    }

                    //Console.WriteLine("blah:" + TimeSpan.FromSeconds(Double.Parse(num)));

                }
                else
                {
                    if (nums.Count > 0)
                    {
                        if (nums[nums.Count - 1].TotalSeconds != 0)
                        {
                            nums.Add(TimeSpan.FromSeconds(0));
                            Console.Write("^");
                        }
                    }
                    //Console.WriteLine("sigal:" + line);
                }
            }
            Console.WriteLine("#");
            Console.WriteLine("Confirming Breaks...");
            for (int i = 1; i < nums.Count; i++)
            {
                if (nums[i - 1].TotalSeconds == 0 && nums[i].TotalSeconds == 0)
                {
                    nums.RemoveAt(i);
                    Console.Write("-");
                }
            }
            List<TimeSpan> commerical_breaks = new List<TimeSpan>();
            commerical_breaks.Add(TimeSpan.FromSeconds(0));
            int last = 0;
            for(int i = 0;i<nums.Count;i++)
            {
                TimeSpan t = nums[i];
                //Console.WriteLine(i + " - " + t.ToString());
                if (t.TotalSeconds == 0) //start new count
                {
                    if (last != 0)
                    {

                        TimeSpan q = nums[last+1];
                        TimeSpan qa = nums[i-1];
                        //Console.WriteLine("Total: " + (qa - q).TotalSeconds + " - " + qa.ToString() + " - " + q.ToString());
                        AddLog("Total: " + (qa - q).TotalSeconds + " - " + qa.ToString() + " - " + q.ToString() + " ticks:" + (qa - q).Ticks + " thresh hold:" + TimeSpan.FromSeconds(threshhold).Ticks);
                        if ((qa - q).Ticks > TimeSpan.FromSeconds(threshhold).Ticks)
                        {

                            //Console.WriteLine("Found commercial break at " + qa.ToString());
                            AddLog("Found commercial break between (" + q.ToString() + "," + qa.ToString() + ")");
                            TimeSpan tdiff = qa - q;
                            AddLog("Using difference: " + (q + new TimeSpan(tdiff.Ticks / 2)).ToString());
                            commerical_breaks.Add((q + new TimeSpan(tdiff.Ticks / 2)));
                            Console.Write("*");
                        }
                        last = i;
                    }
                    else
                    {
                        last = i;
                    }
                }

                //Console.WriteLine(t.ToString());
            }
            Console.WriteLine("#");
            Console.WriteLine("Commercial breaks found: " + commerical_breaks.Count);
            AddLog("Commercial breaks found: " + commerical_breaks.Count);
            //Console.ReadKey();
            proc.Close();

            TimeSpan lt = new TimeSpan(0, 0, 0);
            List<TimeSpan> new_com = new List<TimeSpan>();
            foreach (TimeSpan t in commerical_breaks)
            {
                if (t.TotalMinutes - lt.TotalMinutes > 5 || lt.TotalMinutes == 0 || threshhold == 0)
                {
                    new_com.Add(t);
                    AddLog("New Found commercial break at " + t.ToString());
                    //Console.WriteLine("New Found commercial break at " + t.ToString());
                    Console.Write("+");
                }

                lt = t;
            }

            return new_com;

            //return commerical_breaks;
        }