T2-MI — packed DVB-T2 programmes
Updated 25 Oct 2026Some satellite transponders (and some distribution networks) carry the programmes of a terrestrial DVB-T2 network packed into T2-MI (ETSI TS 102 773) on a single PID — the feed that goes to the terrestrial transmitters. Without decapsulation, such a mux shows a single data service and no picture.
Castreon extracts the inner stream (the TS of one PLP), and the programmes in it become ordinary services: you scan them, make channels from them, and the TV guide, descrambling and alerts work the same.
Available from Castreon 1.9.0, in all plans, on any adapter: a local card or a SAT>IP server.
Turning on decapsulation
In DVB adapters, open the adapter tuned to the transponder with T2-MI (or add it), then turn on T2-MI (decapsulation):
- T2-MI PID — leave the field empty and Castreon finds the PID that carries T2-MI by itself (usually
4096); you can also type it (32–8190). - PLP — leave the field empty for the first PLP found, or type the PLP number you want (0–255).
After saving, the adapter tunes again. Click Scan: the programmes from the T2-MI stream appear, and you make channels from them as from any other mux.
On a SAT>IP server with Requested PIDs → Only the ones in use, the T2-MI PID must be typed: the automatic search needs the whole mux.
What you see in the panel
The adapter panel shows:
- T2-MI PID — marked found automatically if Castreon found it;
- PLP — the chosen one, plus how many PLPs were found in the stream and their numbers (so you can pick another one if needed);
- Extracted T2 stream — the bitrate of the inner stream, with the transport mode: NM (normal) or HEM (high efficiency), and NPD if the transmitter side deleted the null packets;
- T2-MI errors — T2-MI packets with a wrong checksum and lost inner packets; shown only when there are some, usually because of losses in the satellite signal.
If Castreon finds no T2-MI stream a few seconds after tuning, the panel says so: either the transponder has no T2-MI, or the PID must be typed by hand.
Castreon rebuilds the packets in normal mode and in high-efficiency mode, with or without ISSY, and with NPD it puts back the null packets deleted at the transmitter side, so the bitrate and the timestamps of the programmes stay the original ones.
How much is verified: decapsulation is verified in automated tests: we pack TS streams into T2-MI ourselves (normal mode, high efficiency, ISSY, NPD, two PLPs, losses and corrupted data) and check that exactly the stream that went in comes out. In-band signalling is not used. If a real T2-MI feed shows errors all the time, open a ticket with the satellite and the transponder parameters.
What it does not do yet
- several PLPs from the same adapter at once — one adapter extracts one PLP (another PLP needs another tuner, so another adapter);
- T2-MI from IP sources (UDP, SRT, HTTP) — only from DVB adapters.