[linux-dvb] RFC - XML channel listings

[Dave Chapman <dave@dchapman.com>]

As far as I can tell, there is no standard format for storing lists of 
satellite channels, so I've been working on an XML-based solution.

I am working on two related formats - one to store the raw information on 
channels (i.e. satellite, transponder, frequency, polarity, vpid, apid) and 
another to represent how these are shown to the users - i.e. grouping and 
ordering of a subset of channels.

An example (listing one TV station with multiple audio streams) is:

<xmlsat>
<location id="0070">
<satellite name="Eutelsat W3" id="EUT0W3">
<transponder name="C9" freq="11387" pol="h" beam="KW">
<channel name="Euronews" pnr="4" sr="27500" fec="5/6" type="tv" ca="0">
<video pid="2221" />
<audio lang="fr" pid="2231" />
<audio lang="en" pid="2232" />
<audio lang="de" pid="2233" />
<audio lang="it" pid="2234" />
<audio lang="es" pid="2235" />
<audio lang="pt" pid="2236 />
<audio lang="en" pid="2237 />
</channel>
</transponder>
</satellite>
</location>
</xmlsat>

As you can tell the (strict) hierarchy of the elements is:

Location (orbital position)
Satellite
Transponder
Channel
Video/Audio pid(s)

I'm only concentrating on digital broadcasts, but the principle could be 
applied to analogue broadcasts if there was a reason to.  I've also chosen to 
use attributes instead of elements - it seems cleaner to me

The above example is not complete - other information could be stored, for 
example: the type of programming, the hours of broadcast for a channel, it's 
country of origin, a web address for listings etc.  The principle is that it 
stores information about broadcasts, not about your receiver's settings.

I have written a filter (in awk) that processes the HTML files from 
www.satcodx.com into this format, and also a C parser (using libxml) that 
reads these files from disk to memory.  I'll release these under the GPL if 
anyone wants them.  

Filters could easily be written to convert channel listings to/from any other 
format in common use.  The "pscan" program couldalso usefully be modified to 
output listings in this format. 

The second issue is how to map this (huge) master list of channels into a 
user-defined list of channels in an application like VDR.   My initial 
thought is to use another XML file containing lists of channels (just the 
satellite and pnr for each channel) arranged into a set of hierarchical 
namedgroups, but this issue needs more thought.

Comments are welcome.  Am I wasting my time?

Regards,

Dave Chapman.


--- 
Info:
To unsubscribe send a mail to listar@linuxtv.org with unsubscribe as subject.