System level block diagrams

[techfreakz]

Hello everyone,

I'm interested in the concept of DVB-C reception, decoding and viewing in the UK using a dedicated PC platfrom (x86 rather than 64bit at the moment).

All of the descriptions of the various elements involved, (e.g. recieve/digitise, demod, decrypt (CI/CAM/CARD), decode & display etc) discribe the individual elements well, but not how they hang together or what data & streams flows between them.

Has anyone got a clear system level block diagram of the various elements? Perhaps showing things like the following:

CABLE--rf-->DEMOD--MpegTS-->CAM--MPegPS-->DECODE--a/v->DISPLAY
.............................................. |....................... |...........................
......................... CARD--keys---^........................ |-(EPG)-->CHANNEL SELECT
............................ ^------------------(Key AU)---|

I'm particularly interested in implementing all this (bar the tuner) in a Linux Virtual Machine that has the ability to compress & re-stream the video. Perhaps using VLC's functionality in this field. So video can be accessed as a stream from a media centre, remotely via a web browser and on mobile phone, perhaps using MPeg4/H263.

Best regards

TFZ

[TheCoder]

You can try taking a look at some of the ETSI dvb standards documents. There's bound to be a flow diagram in one of them somewhere explaining the basic concepts.

Quite a bit of the internals though (especially when to comes to the CSA descramblers) are still available only under NDA so you'll have to do quite a bit of digging to find usable details.

Generally though, you can think of a TS stream as a multi-program dvd where all the various channels are multiplexed together in a single fast bitstream (usually around 40Mbits/sec). If you extract a single program then its very easy to convert that streamset into a standard DVD datastream, so, if you have a program to play DVD's then your already a long way towards having a program to play DVB !