Re: DVB over RTP

[David Podeur <david@convergence.de>]

* @rtur Lugmayr <lartur@acm.org> [000616 10:46]:

> rtp provides 3 types of encapsulating an MPEG stream:
> payload based on encapsulating PS and TS

RFC2250.
2. Encapsulation of MPEG System and Transport Streams

> payload based on seperate packetisation of MPEG audio/video ES and

RFC2250.
3. Encapsulation of MPEG Elementary Streams

> payload based on joint packetization of mpeg2 audio/video ES =
> bundled MPEG format).

RFC2343.

> > Do you know if someone has already implemented this DVB-RTP gateway?
> > If so, can you give me some links?
> > Can we do it, using "Mpeg-2 TS over RTP" and linux driver?

"MPEG2 TS over RTP" from linuxtv.org is a raw implementation of
RFC2250-2. It packs the MPEG2 188bytes packets into RTP Packets (several
MPEG-2 packets per RTP packet, according to the MTUi defined).

DVB is directly compatible with MPEG-2 transport packets. As far as I
have understood it, DVB just adds a few FEC techniques so that the
transmission becomes almost QEF (Quasi Error Free) in spite of the
tranport step (satellite link, ...).

So the answer for the first item is yes: "MPEG2 TS over RTP" will
do the job, provided you have an MPEG-2 transport stream.

But then you have to get this TS... and for that purpose there is nothing
to exect from the siemens card. You will never get a full TS from it
(see previous mails from Ralph Metzler).

This does not means you will not be able to RTPize digital TV sessions
with the siemens card, as it gives you an AV_PES stream, wich is nothing
else than an MPEG-2 program stream limited to 1 video and 1 audio
canals (this is actually my thesis)

Moreover, with a full DVB stream, you will deal with something like a
38Mbit/s traffic. You may be able to handle it "on the fly", but i will
be harder to get such a bitrate from a storage unit (harddisk...).

Hope it helps,
David.

-- 
david@convergence.de