Vijay,

There is actually no simple and straightforward answer to any system
supporting Digital Video Broadcasting because it is a multilayer
architecture.

DVB uses MPEG-2 Transport Streams (MP2TS) as defined by ISO/IEC 13818-1
Systems with DVB-specific Service Information (SI) as specified in ETSI EN
300 468.

For transmission these streams are modulated onto a bearer. What the bearer
is depends on the transmission system. Hence, DVB specifies multiple
standards: DVB-S and DVB-S2 for satellite transmission, DVB-SH for satellite
transmission to handhelds, DVB-C and DVB-C2 for cable transmission, DVB-T
and DVB-T2 for terrestrial transmission, and DVB-H for terrestrial
transmission to handhelds. The standards use different modulation and
modulation schemes such as QAM, PSK, QPSK, APSK, etc. Most recently
DVB-compliant MP2TS are also used in IPTV and there the transmission is an
IP network using UDP unicast/multicast and/or TCP dependent on the
application. Sometimes for IPTV the streams are RTP-encapsulated and may
also use Quality of Experience (QE) technologies such as Cisco's VQE or
Alcatel-Lucent's FCC/RET.

Here starts the first layer of the problem. Dependent on how your MeeGo
system will receive the DVB MP2TS you will need hardware to do the
demodulation. For that you will obviously a driver, typically a character
device driver as kernel module. If your system receives the stream via IP
you are all set.

Once you got to MP2TS you will have to demultiplex it. MeeGo uses gstreamer
and one of the container formats it supports is MP2TS. After that the
elementary streams need to be decoded. Most importantly video and audio and
for that gsteamer supports a variety of codecs. If you need to be able to
decode the SI for EPG etc. in the DVB MP2TS then you will probably need a
plugin for gstreamer to decode it.

DVB television programs may be encrypted with a CA system. That adds another
layer of complexity since you wont be able to decode the elementary streams
unless they are decrypted. DVB systems mostly use transport scrambling
control meaning the payload of the MP2TS packets is encrypted. What packets
are encrypted is indicated by the 2 TSC (transport scrambling control) bits
in the MP2TS header.

Best regards,
Rudi



On Wed, Oct 27, 2010 at 10:43 PM, vijay singh <[email protected]> wrote:

> Hello,
> I want to know do we have support for DVB under MeeGo 1.0 or planned
> MeeGo 1.1 release.
>
> Bye--
>
> _______________________________________________
> MeeGo-dev mailing list
> [email protected]
> http://lists.meego.com/listinfo/meego-dev
>
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