RtpSend.cs

using System.Diagnostics;
using System.IO;
using System.Net.Sockets;
using System.Threading;

namespace RtpTest
{
    class Program
    {
        static void AnnouncementThread()
        {
            byte[] announcement =
		    {
			    0x20, 0x00, 0x7E, 0x58, 0x00, 0x00, 0x00, 0x00, 0x61, 0x70, 0x70, 0x6C,
			    0x69, 0x63, 0x61, 0x74, 0x69, 0x6F, 0x6E, 0x2F, 0x73, 0x64, 0x70, 0x00,
			    0x76, 0x3D, 0x30, 0x0A, 0x6F, 0x3D, 0x2D, 0x20, 0x30, 0x20, 0x30, 0x20,
			    0x49, 0x4E, 0x20, 0x49, 0x50, 0x34, 0x20, 0x2D, 0x0D, 0x0A, 0x73, 0x3D,
			    0x45, 0x75, 0x70, 0x68, 0x6F, 0x6E, 0x0D, 0x0A, 0x63, 0x3D, 0x49, 0x4E,
			    0x20, 0x49, 0x50, 0x34, 0x20, 0x30, 0x2E, 0x30, 0x2E, 0x30, 0x2E, 0x30,
			    0x2F, 0x32, 0x35, 0x35, 0x0D, 0x0A, 0x74, 0x3D, 0x30, 0x20, 0x30, 0x0D,
			    0x0A, 0x6D, 0x3D, 0x61, 0x75, 0x64, 0x69, 0x6F, 0x20, 0x35, 0x30, 0x30,
			    0x34, 0x20, 0x52, 0x54, 0x50, 0x2F, 0x41, 0x56, 0x50, 0x20, 0x31, 0x30,
			    0x0D, 0x0A
		    };

            using (var client = new UdpClient("192.168.0.103", 9875))
            {
                client.Send(announcement, announcement.Length);
                Thread.Sleep(1000);
            }
        }

        static void Main()
        {
            new Thread(AnnouncementThread) { IsBackground = true }.Start();

            //var timer = new Timer(null, null, 0, 10);
            var buffer = new byte[2000];
            var sampleBuffer = new byte[2000];
            uint timestamp = 0;
            ushort seqNo = 0;
            var ssrc = 3L;

            buffer[0] = 0x80;
            buffer[1] = 0x8a;
            buffer[8] = (byte)(ssrc >> 24);
            buffer[9] = (byte)(ssrc >> 16);
            buffer[10] = (byte)(ssrc >> 8);
            buffer[11] = (byte)ssrc;

            using (var udpClient = new UdpClient("192.168.0.103", 5004))
            using (var input = File.OpenRead(@"foo.raw"))
            {
                const int frames = 441;
                
                var readTask = input.ReadAsync(sampleBuffer, 0, frames * 4);
                while (true)
                {
                    buffer[2] = (byte)(seqNo >> 8);
                    buffer[3] = (byte)seqNo;
                    buffer[4] = (byte)(timestamp >> 24);
                    buffer[5] = (byte)(timestamp >> 16);
                    buffer[6] = (byte)(timestamp >> 8);
                    buffer[7] = (byte)timestamp;

                    var len = readTask.Result;
                    if (len <= 0)
                        break;
                    var readFrames = len / 4;
                    for (var i = 0; i < readFrames; i++)
                    {
                        buffer[12 + i * 4] = sampleBuffer[i * 4 + 1];
                        buffer[13 + i * 4] = sampleBuffer[i * 4];
                        buffer[14 + i * 4] = sampleBuffer[i * 4 + 3];
                        buffer[15 + i * 4] = sampleBuffer[i * 4 + 2];
                    }

                    var sw = Stopwatch.StartNew();
                    var sendTask = udpClient.SendAsync(buffer, 12 + readFrames * 4);
                    sendTask.ContinueWith(t =>
                    {
                        if (sw.ElapsedMilliseconds > 5)
                            System.Console.WriteLine(sw.ElapsedMilliseconds);
                    });

                    seqNo++;
                    timestamp += (uint)readFrames;
                    buffer[1] = 0x0a;

                    readTask = input.ReadAsync(sampleBuffer, 0, frames * 4);
                    Thread.Sleep(10);
                }
            }
        }
    }
}