Patrick Boettcher wrote:
> On Mon, 13 Jun 2005, Manu Abraham wrote:
>> What i had been doing was ca_zap was split up into 2 libs. One for
>> parsing si
>
> When I implemented PSIP-scanning to dvbscan I looked for a libsi to use
> for section parsing, but I didn't find anything useful. I wrote
> something for myself for scan (see atsc_psip_section* in utils/scan). In
Hmm, the same way i was when i started up with ca_zap. I ended up
writing a monolithic ca_zap which could not be modified at all for any
other applications/bug-fixing.. It took me around 2 to 3 months (?) to
get it to this state, since we had too much of a discussion.. ;-)
> fact it is a perl-script which generates c and header-files to have easy
> and transparent access (no bitshifting and -masking in scancode) to
> section-structures in scan. The current version lacks reading
> variable-length string-fields, but I think this is solvable (libsi
> should do the memory-management).
>
It is not a complete SI parser, at the moment it handles only PAT and
PMT tables..
What i do is the bit-shifting and masking is done by specific routines,
such that it look very clean indeed..
I think i should finish off ca_zap and libs such that you guys can take
a look at it at the earliest.. Actually i have some quite modular code
right now, thanks to the pressure Dominique put up..
> Parsing the section in the application looks like this:
>
> struct ATSC_service_location_element e =
> read_ATSC_service_location_element(b);
>
> accessing it:
>
> switch (e.stream_type) {
> case 0x02: /* video */
> s->video_pid = e.elementary_PID;
>
I parse the descriptors the same way.. But hand coded..
> and so on.
>
> What do you think? Could this be a way to go on for SI?
>
Hmmm.. i use quite some PAT and PMT parsing. I am doing a couple of
descriptors at the moment. I was planning to add in parsing NVOD
descriptors too for some stuff that i was working on for some NVOD
decryption for DVB-S (Actually the modularization really helps there, as
code duplication is really avoided)
I have quite some code there, if i happen to switch, that would make
myself to rewrite hell a lot of code. The way i worked it out,
liben50221 depends heavily on libsi, as CA_PMT objects are derived from
SI only.
So it does not make much sense for me to switch over. In fact that would
mean a complete rewrite ? If i am correct ..
Manu
