Adrian Caspersz
>Hmmm.... How API accessible is the EPG information from a DVB-T and
>DVB-S from these USB dongles?
>
>Reason I'm asking is, I've seen a few requests around these parts
>(err... Brian..) for a 'talking EPG', 'voice controlled remote', even
>'voice controlled PVR' for use by the blind / partially sighted.
>
>Don't seem to be those features available built into consumer
>electronics, something which the RPi could be knocked into doing?


It is basically easy, for example for DVB-T here, the basic  script to show
nl-1 is:
dvbstream  -c 0  -I 2  -qam 64  -gi 4  -cr 1_2  -crlp 1_2  -bw 8  -tm 8  -f
562000  -o 7011 7012 7013  | jpvtx 7013 | mplayer  -cache 8192  -vf yadif  -
that gets video (PID 7011), audio (PID 7012)  and ceefax (PID 7013).

If you however typed:
dvbstream  -c 0  -I 2  -qam 64  -gi 4  -cr 1_2  -crlp 1_2  -bw 8  -tm 8  -f
562000  -o 8192 > /root/q1.ts
then you record the whole transponder (the whole transmitter content for that
frequency) to file /root/q1.ts

Stop it with control C after a few minutes (file will get VERY big), and then
type:
mediainfo /root/q1, then you see this (maybe needs apt-get install mediainfo):

root@raspberrypi:~# dvbstream  -c 0  -I 2  -qam 64  -gi 4  -cr 1_2  -crlp 1_2 
-bw 8  -tm 8  -f 562000  -o 8192 > /root/q1.ts
dvbstream v0.5 - (C) Dave Chapman 2001-2004
Released under the GPL.
Latest version available from http://www.linuxstb.org/
Using DVB card "Realtek RTL2832 (DVB-T)"
tuning DVB-T (in United Kingdom) to 562000000 Hz
polling....
Getting frontend event
FE_STATUS:
polling....
Getting frontend event
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
Bit error rate: 757
Signal strength: 0
SNR: 221
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
Setting filter for PID 2
Setting filter for PID 1
Setting filter for PID 8192
Output to stdout
Streaming 3 streams
^C Caught signal 2 - closing cleanly.

Now typing:
mediainfo /root/q1.ts
shows this (I uploaded it to my website else this posting gets too long):
 http://panteltje.com/pub/info.txt

There is all the info about what happens on that frequency (transponder).
Using PID 8192 passes the whole transport stream, that is a feature of the
Linux driver.
Scroll down in that file and you have all the program info as ASCII text.

We see then for example menu 1 for program video 7010, it specifies menu ID
1101

It should be possible to filter and decode only the 1101 stream or is it 7010
stream text part?

There is of course also videotext, or for the English ceefax with program and
other info.
I did write a decoder for that,
this script filters out only the ceefax (the Dutch call it teletext) for nl1
for example:
 dvbstream -c 0 -I 2 -qam 64 -gi 4 -cr 1_2 -crlp 1_2 -bw 8 -tm 8 -f 562000 -o
7013 | jpvtx 7013  > /dev/zero
-------------------------------------------------------------------------------
------^^^^^^^^^^

'jpvtx' is the ceefax decoder I wrote, its stores all pages in directory
/video/vtx/1/
jpvtx is here:
 http://panteltje.com/pub//jpvtx-0.2.1.tgz
is easy to compile with gcc.

To view those pages I wrote xvtx-p, it reads that directory /video/vtx/1/ and
display it in X,
4 pages at the time, you can click on page numbers, save pages too:
 http://panteltje.com/panteltje/satellite/jpvtx-0.2.1.tgz
should be no problem connecting some voice synthesizer to it.
I use 'festival' sometimes for other things like spoken alarms etc.

You can combine jpvtx with normal video viewing like this for example
(screenshot taken just now):
  http://panteltje.com/pub/xvtx-p-nl_now.gif

I do not know much about voice control,
I had some voice control to show things, scripts like you can say:
show BBC1
for the PC but have not tried voice recognition on the rapi.
One problem with voice control is false positives, so I stopped using it.
Can look up some old code if you want.
But maybe a simple joystick with talking menu could also work.

Ask if you need more specific info, been playing with video a long time.

Maybe I could help.

--- SoupGate-Win32 v1.05