8) Channels and Feed in 4:2:2 format
Many broadcasting stations that transmit on satellite use standard MPEG-2.
For feeds, it is necessary make distinction among MPEG-2 "4:2:0" used by television chains and MPEG-2 "4:2:2" used more frequently for feeds (particularly those of EBU).
The first standard (4:2:0) is decoded on almost all the numerical receivers and allows to receive
majority of programs and feeds.
To visualize a transmission compressed in 4:2:2, an additional equipment is necessary: a devoted terminal, a DVB-S
card with decompression software or still a Nokia 9500/9600 with DVB2000 connected to PC with SCSI interface.
Fortunately
Skystar
2 is able to visualize without problems 4:2:2 format. Unfortunately only some codecs, as the Elecards and the Dscalers support this standard,
and so you must first set your DVB software on Codec Video = ELECARD.
From some tests has emerged that:
Elecard = Visualization OK
Dscaler = Visualization OK
Nvidia = it Visualizes only first image with altered colors but audio is active
Cyberlink = Visualization lines or
mosaic error
Intervideo = black Screen
Sonic = black Screen but active audio
Mainconcept = Crash
software
Further technical information on the compression 4:2:2:Link Engs -PDF Ita
Encrypted Feeds
Still today, the
big part of feeds are transmitted in clear.
Nevertheless sporting broadcasting stations of certain countries (France, Belgium.) are
encryipted (often in NTL) to protect their rights of diffusion.
The most important events are encoded in RAS and BISS for which we want correct underline this for avoid false hopes in whoever believes that in feedhunting all is simple and free.
RAS / NTL is for Remote Access System, NTL
is the English that develops the coding.
BISS = Basic Interleaved Scrambled System.
Probably you are asking "But
how i can say that a found frequency is a feed if cannot succeeds in viewing?"
Analysis of a encrypted feed, seen by the outside can result even also
incomprensive, .
In reality there is very more behind, very more terms
recognizable from various components that constitute nucleus of a feed.
First of all it is really the extreme complexity of the interlacements that brings to setup and lighting of a feed, correlated to the canons (and even simple because often repeated) "fundamental" (what frequency, pol, sr) to bring back the feeds and the feedhunting to a sort of mix among certain elements.
(the complete article of Stanley Cassidy on
encrypted Feed is available on
Digital-Forum)
9/9
NEXT >>
FEED INTRODUCTION
1)
What are "feeds"?
2) Feed Archive
3)
Requirement
4) Hunting?
SEARCHING METHODS
5) Direct insertion
6) Charts
based search
7) Blind search
8)
Feed in 4:2:2 format and encrypted
9)
Conclusions