HDTV

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Andy G8SIK
Posts: 3
Joined: Sun Mar 02, 2008 4:38 pm

HDTV

Post by Andy G8SIK » Sun Mar 02, 2008 5:41 pm

Hi,
I have been trying to catch up on the jargon to do with HDTV, mostly by looking at Wikipedia, and want to ask some questions.

Here's one:- Sky Tx using both 1080i50 and 720p50, do BBC-HD and 4HD Tx both stds?

Also:- If a Blu-Ray player delivers 1080PsF25 and that is the same as 1080i25 but includes a code to tell the Rx that its odd and even fields are from the same "film" frame, do the broadcasters send the same code when they Tx a movie?

I wonder if any member working in TV knows the answers or can suggest where to look up the answers.

73 Andy G8SIK

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trevorb
Posts: 19
Joined: Fri Feb 22, 2008 5:16 pm

Re: HDTV

Post by trevorb » Sat Mar 08, 2008 3:42 pm

Here's one:- Sky Tx using both 1080i50 and 720p50, do BBC-HD and 4HD Tx both stds?
I thought that the moden flat screens we agile across all these standards I don't have HD, just the flat screen like most of the public. So can sky not just transmit the native standard and it gets sorted in the home?

If a Blu-Ray player delivers 1080PsF25 and that is the same as 1080i25 but includes a code to tell the Rx that its odd and even fields are from the same "film" frame, do the broadcasters send the same code when they Tx a movie?

The words are now 25p for pictures ie 2 scans on an i system 1 scan on a P system although all the flat screens are progressive

Blur Ray I have not read up but since
HD DVD received fatal blow :-

HD DVD has received a fatal blow with the impending announcement that Toshiba is pulling out of the war between Blu-ray and HD DVD.
Shares in Toshiba gained 5.7% as speculation intensified that the electronics giant is to scrap its high definition DVD format. Toshiba confessed that it was reviewing its business strategies but added it had made no decision over HD DVD's future.
HD DVD has suffered over recent months. A number of major US film studios announced their support for Blu-ray – leaving just Universal Pictures and Paramount favouring HD DVD. Last week, Wal-Mart, the world's largest retailer, announced it would only sell high-definition DVDs in the Blu-ray format at its 4,000 US stores.
John Lewis said that it did not expect to order more supplies of HD DVD players and the video rental firms, Blockbuster and Netflix, have said they will phase out the Toshiba-backed format.
Despite the benefit of HD DVD being relatively backward compatible and the recent approval by DVD Forum of the evolutionary HD DVD China format – which sweeps away any data capacities currently offered by standard HD DVD or Blu-ray, it seems that brand perception has won the war for Blu-ray in the video market sector.

Lets see if that sparks some debate

Andy G8SIK
Posts: 3
Joined: Sun Mar 02, 2008 4:38 pm

Re: HDTV

Post by Andy G8SIK » Sat Mar 15, 2008 6:00 pm

Thanks for your reply Trevor.

I must be more careful when referring to the 1080 interlace std. It is 1080i25 and not 1080i50 which could mean it has a field rate of 100Hz.

Since I posted my questions I have visited BBC.CO.UK/HDTV and read two docs for guidance for producers. The producer may choose the production std, either 1080p25 or 1080i25, but the Tx tape must be recorded with the 1080i25 std for delivery to the BBC. 1080p25 is said to have the "film look".

When the two types of signal arrive at the Sat set top box they are sent down the HDMI cabel to the TV. If it has a 720p LCD display then the 1080i25 signal has to be converted to 720p50. If it has a 1080p LCD display then both the 1080i25 and 720p50 signals have to be converted to 1080p50. A salesman in John Lewis told me that only some HD Ready TVs could accept the 1080p25 signal from a BluRay player. Those that did accept it must have converted it to 1080p50 or maybe they can display it direct, if LCD screens do not suffer from flicker.

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