TSReader |
IP/DVB |
Introduction
MPEG-2 transport streams don't just contain video and audio streams - there are many data streams that can be carried along side the MPEG-2 components such as IP traffic. A classic example being private distance learning networks where the video and audio presentation is encoded at a low bitrate using MPEG-1 and then moved into UDP/IP packets which are then carried on a PID in the transport stream. At the other end, an IP/DVB router removes the headers used to transport the UDP/IP packet over the MPEG-2 network and then retransmits the packet onto the local area network. PC users can then watch the program at their desk by receiving the stream with a multicast player application like Cisco IP/TV or VLC.
TSReader 2.4.34 and later can save the data (the payload) that's carried in these packets and/or retransmit them as UDP/IP packets onto your LAN - in effect making TSReader act like an IP/DVB router.
Requirements
For the retransmit function you first need to install WinPcap - it's free and available from http://www.winpcap.org/
It's probably also a good idea to ensure you've got the latest version of VLC.
Using the save function
If you want to save the payload from an IP/DVB stream follow these steps. By payload we mean the data portion of the IP/DVB packet, i.e. the section minus the MPE, IP and UDP or TCP headers.
Using the retransmit function
This function makes TSReader act like an IP/DVB router by taking the packets from the MPEG-2 stream and re-transmitting them onto your LAN.
The retransmit function currently only supports multicast UDP streams - TCP is currently not supported.
Finding port numbers
For many playback applications likeVLC you need the UDP port number used for the transmission. Since TSReader can retransmit packets onto your LAN, you just use a packet sniffer program to decode the packets and show you the port number.
Ethereal is free and just happens to use the WinPcap interface you already got for TSReader. That's what we use to decode port numbers.