Stream Info

[regulator]

This has been bugging me, and I hope someone here can shed some light on it.

I've been doing some reading on MPEG-TS, PES structure etc and cannot figure out how my DM500 (I don't use it with a sub card) can figure out the resolution, frame rate etc of a stream even if it is scrambled (ie a F*x channel).

From what I understand, the TS header while transmitted clear does not include any stream specific info like the above and nor does the PES packet (but its scrambled anyway). The info seems to be in the MPEG stream itself, contained within the PES structure.

Is this info also carried someplace else like the PMT or does the box just guess based on bitrate or something like that?

Thanks for any info :-)

[agarol]

As you suspect, it would be impossible for the decoder to know if that data were encrypted.
Simply, most of the data is not encrypted.
The video and audio is encrypted on encrypted channels.
If you log the data, you will be able to recognize much of the info. For example you will be able to see satellite and transponder data, channel/epg lineups, etc.
Ag

[regulator]

My DM500 tells me the resolution etc even on encrypted channels, so this info is either being guessed or it is contained not only in the MPEG stream (which is not available as its encrypted) but also in descriptor streams like the PMT etc.

Can anyone confirm this?

[Mysterex]

that should explain it all...