Is there a standard way in which subtitling is sent on FTA
satellite?
Can someone suggest a good tutorial on the subject?
thank you,
Robert
>
>On analogue terrestrial TV we make a lot of use of subtitles/captions
>on text page 888. However, those same channels (BBC etc) broadcast
>of satellite do not seem to carry the text pages. At least my cheap
>FTA receiver (a Fortec Star Beta) does not seem to do it.
>
>Is there a standard way in which subtitling is sent on FTA
>satellite?
They are send on a different PID in the transport stream:
show: selected program=bbc1
show: using astra2
Read 44 bytes - Found 8 services
Found program number 0
Found program number 6301
Program number: 6301 PMT pid: 261 (0x105)
pid 5000 (0x1388) video type is mpeg2
Language = eng pid 5001 (0x1389)
Language = NAR pid 5002 (0x138a)
setting PIDS for program number 6301 (0x189d):
video_pid=5000 (0x1388)
found 2 audio channels, pid: 5001 (0x1389) 5002 (0x138a)
selected_audio_pid=5001 (0x1389) language=eng
no ac3 pid found
teletext_pid=5003 (0x138b)
found 7 subtitle channels, pid: 2306 (0x902) 2307 (0x903) 2308 (0x904) 2309 (0x905) 2311 (0x907) 2313 (0x909) 2314 (0x90a)
I dunno if all these PIDs are really subtitles, or even if all are used.
>Can someone suggest a good tutorial on the subject?
I _did_ know how it worked, you need a tutorial on digital TV and the ETSI docs.
There are programs around that will decode and display the subtitles in case of a sat PCI card,
like for Linux mplayer (should so it?), and ffmpeg too?
If all this sounds like Greek to you, then forget it anyways, I am sure modern receivers can
do the subs (I hope).
DarthVader
The Fortec star beta has "Teletext supported by OSD and VBI" according to their
website,
so VBI means you should be able to use the text function of your TV set, if the
inbuilt "OSD"
variant doesn't work.
I have had hanging VBI-processes happen occasionally with different receivers even
though everything else seemed fine. This could be cured by a reboot.
HTH, Miles
The same subtitles are also available in the digital version but the UK
uses a non-standard version of it that is not available on international
STBs due to the need to buy a special licence to distribute the s/w.
Dem
rather belateldly, thank you all for your helpful discussion of this.
I'll play some more woth the Fortec Star beta (FSB). I did at one
point manage to get the teletext pages displayed twice, one via my TV
and at the same time (slightly shofted sideways) as part of the video
image generated by the FSB. I did try 88 but got nothing. Maybe it
was a an unlucky choice of programme.
Robert
I think the BBC indicate subtitled programmes with a [S] in the EPG
data. Many (most?) are subtitled. There's also listings for BBC-1
and -2 in teletext on BBC-1 London and BBC-2 England.
BBC World carries the UK News on teletext page 101 on most broadcasts.
Hope that helps,
--
MJ Ray - see/vidu http://mjr.towers.org.uk/email.html
Cycling on Satellite TV: http://www.cyclingfans.net/satellite
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