[mythtv] DVB EIT in mythtv-eit

jd mythdev at penyball.cix.co.uk
Thu May 4 17:47:00 UTC 2006

> The network ID i have to give the STB is 1111. The NIT which is 
> selected that way has a table id of 0x41 (other network).
> I guarantee though, that it is the valid NIT for my location.
> This is common cable behaviour. This was recorded on Essent in the 
> Netherlands.

I don't remember seeing anything in the dvb spec that precludes the 0x41 
NIT including transports from the current as well as other networks - and 
that may be what is happening

however ETSI EN 300-468 v1.6.1 (2004-11) - the european DVB spec - 
directly equivalent to the ISO spec, says that the following tables are 
mandatory in the DVB stream:  (C, S &T)

NIT Actual network pid=0x0010  table_id=0x40
SDT Actual transport pid=0x0011  table_id=0x42
EIT Actual transport present/following pid=0x0012 table_id=0x4E
TDT Time&date pid=0x0014  table_id 0x70

The following are optional
NIT Other network pid=0x0010 table_id=0x41
BAT Bouquet association pid=0x0011 table_id=0x4A
SDT Other transport pid=0x0011 table_id=0x46
EIT Actual transport - schedule pid=0x0012 table_id=0x50 to 0x5F
EIT Other transport - schedule pid=0x0012 table_id=0x60 to 0x6F
EIT Other transport - present/following pid=0x0012 table_id=0x4F
RST Running status pid=0x0013 table_id=71
TOT Time offset pid=0x0014 table_id=0x73
ST  Stuffing pid=0x0010 to 0x0014 table_id=0x72

try dvbsnoop with the appropriate values and see if they really are 
breaking the spec? Although I suppose there could be a later version that 
allows no 0x40 table - but that ought to break a lot of kit.

Section 5.2.1 of the spec:
5.2.1 Network Information table

The NIT (see table 3) conveys information relating to the physical 
organization of the multiplexes/TSs carried via a given network, and the 
characteristics of the network itself. The combination of 
original_network_id and transport_stream_id allow each TS to be uniquely 
identified throughout the ETS application area. Networks are assigned 
individual network_id values, which serve as unique identification codes 
for networks. The allocation of these codes may be found in ETR 162 [6]. 
In the case that the NIT is transmitted on the network on which the TS was
originated, the network_id and the original_network_id shall take the same 

Guidelines for the processing of SI at transitions between delivery media 
boundaries, e.g. from satellite to cable or SMATV systems, can be found in 
TR 101 211 [7].

IRDs may be able to store the NIT information in non-volatile memory in 
order to minimize the access time when switching between channels 
("channel hopping"). It is also possible to transmit a NIT for other 
networks in addition to the actual network. Differentiation between the 
NIT for the actual network and the NIT for other networks is achieved
using different table_id values (see table 2).

The NIT shall be segmented into network_information_sections using the 
syntax of table 3. Any sections forming part of an NIT shall be 
transmitted in TS packets with a PID value of 0x0010. Any sections of the 
NIT which describe the actual network (that is, the network of which the 
TS containing the NIT is a part) shall have the table_id 0x40 with the
same table_id_extension (network_id). The network_id field takes the value 
assigned to the actual network in ETR 162 [6]. Any sections of an NIT 
which refer to a network other than the actual network shall take a 
table_id value of 0x41 and the network_id shall take the value allocated 
to the other network in ETR 162 [6].

More information about the mythtv-dev mailing list