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576p is not HD


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#1 bytheway

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Posted 07 April 2005 - 03:12 PM

Hello,

I would just like some feedback on this comment: 576p is not high definition, it offers no resolution difference with standard definition and anyone with a deinterlacer could deinterlace standard definition 576i to create what you call "high definition". USA, Japan and recently the UK have 720p and 1080i as their high definition formats, why has Australia added 576p? Australia should bring itselft into line with the rest of the world, otherwise broadcasters will not have to produce true high definition programs.

Ben

#2 bytheway

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Posted 07 April 2005 - 03:13 PM

Duplicate

Edited by Coral, 07 April 2005 - 07:51 PM.


#3 nexx

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Posted 07 April 2005 - 03:26 PM

You'll find just about everybody here agrees with you.
But the guys who set the dtv legislation obviously didn't :/

Personally I dont even bother with the 576p channels, the SD channels look better anyway.

#4 SPDF

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Posted 07 April 2005 - 03:59 PM

Hello,

I would just like some feedback on this comment: 576p is not high definition, it offers no resolution difference with standard definition and anyone with a deinterlacer could deinterlace standard definition 576i to create what you call "high definition".  USA, Japan and recently the UK have 720p and 1080i as their high definition formats, why has Australia added 576p?  Australia should bring itselft into line with the rest of the world, otherwise broadcasters will not have to produce true high definition programs.

Ben

<{POST_SNAPBACK}>


I Bloody well agree with you (sorry for swearing but I'm Not Happy Jan!)! I think it's an absolute disgrace ABC have abandoned their 1480x780 standard (think they were the numbers) to go to 576p! I have given ABC a big miss since they did this as I used to love their docos (particularly Richard Attenborough) in true HD.

I just hope others don't follow their lead!

#5 DavoNogo

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Posted 07 April 2005 - 04:06 PM

actually, there is a difference:

http://img94.exs.cx/...tarship43kg.gif

http://img207.exs.cx...tarship35qn.gif

http://img207.exs.cx...tarship29pd.gif

http://img203.exs.cx...tarship12iv.gif

#6 ChrisM

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Posted 07 April 2005 - 04:06 PM

I would just like some feedback on this comment: 576p is not high definition, it offers no resolution difference with standard definition and anyone with a deinterlacer could deinterlace standard definition 576i to create what you call "high definition".  USA, Japan and recently the UK have 720p and 1080i as their high definition formats, why has Australia added 576p?  Australia should bring itselft into line with the rest of the world, otherwise broadcasters will not have to produce true high definition programs.



The answer to this, IMHO, is yes and no. No, because the material that broadcasters currently transmit as 576P is no better than well de-interlaced 576i, and most of the time much worse.

Yes, because 576P should have resolution advantages over 576i for the following reasons:

1. Better temporal resolution if 576P is shot as 50 discrete progressive frames, i.e. true 576 50P

2. Better spacial resolution, for two reasons. Firstly, 576P does not suffer from interline flicker problems, so the full resolution of the medium can be utilised. For example, a typical SD camera can only resolve about 405 actual vertical lines in a picture, but a 576P image should have higher resolution, esp. as newer cameras use high definition chips and scale to 576P.
Secondly, with 576P all 576 lines can resolve a moving subject every 50th of a second. 576i can really only use 1 field (288 lines) to resolve a moving subject, as it's only when the two fields line up that the full 576 lines are available.

This should not be misconstrued to suggest I support 576P as an HD format. I think 720P is the go, and the current manifestations of 576P are a joke.

#7 jsmith

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Posted 07 April 2005 - 04:13 PM

I would just like some feedback on this comment: 576p is not high definition, it offers no resolution difference with standard definition and anyone with a deinterlacer could deinterlace standard definition 576i to create what you call "high definition".  USA, Japan and recently the UK have 720p and 1080i as their high definition formats, why has Australia added 576p?  Australia should bring itselft into line with the rest of the world, otherwise broadcasters will not have to produce true high definition programs.


The answer to this, IMHO, is yes and no. No, because the material that broadcasters currently transmit as 576P is no better than well de-interlaced 576i, and most of the time much worse.

Yes, because 576P should have resolution advantages over 576i for the following reasons:

1. Better temporal resolution if 576P is shot as 50 discrete progressive frames, i.e. true 576 50P

2. Better spacial resolution, for two reasons. Firstly, 576P does not suffer from interline flicker problems, so the full resolution of the medium can be utilised. For example, a typical SD camera can only resolve about 405 actual vertical lines in a picture, but a 576P image should have higher resolution, esp. as newer cameras use high definition chips and scale to 576P.
Secondly, with 576P all 576 lines can resolve a moving subject every 50th of a second. 576i can really only use 1 field (288 lines) to resolve a moving subject, as it's only when the two fields line up that the full 576 lines are available.

This should not be misconstrued to suggest I support 576P as an HD format. I think 720P is the go, and the current manifestations of 576P are a joke.

<{POST_SNAPBACK}>

The de-interlacing, or progressive scanning of the screen requires the scanning rate of the screen to be doubled also, otherwise the progressive scanning would be unwatchable and you would see the scanning lines. This does make the picture more stable, and yes does get rid of interline flicker. The problem is as I'm sure you will agree that the resolution is not increased, and thus is why it has been named "extra definition" everywhere else, except here. I really agree with your comment that ABC should go back to 1080i, even though the programs were upconverted standard anyway, as the other guy said the doco's looked excellent at 1080i...

JSmith

#8 BlueDusk

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Posted 07 April 2005 - 04:22 PM

Did you deinterlace the SD version? If you did that's not necessary (when its 25p film content) and it reduces the resolution by half.

#9 ChrisM

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Posted 07 April 2005 - 04:31 PM

The problem is as I'm sure you will agree that the resolution is not increased



No I don't agree, becasue as I explained, real 576 50P (not deinterlaced 576i) does have higher resolution than 576i. There's a differance between progressive display scanning and progressive origination.

I do agree, however, that it's not a big enough resolution difference to have the same impact as real 720P/1080i/P HD, and so deserves the title ED.

#10 DavoNogo

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Posted 07 April 2005 - 04:34 PM

sorry, i should've mentioned that i'm comparing HDTV to DVD.. and i've just re-read the first post, which makes my comparison invalid... me too :blink:

#11 Santa

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Posted 07 April 2005 - 04:38 PM

By the way bytheway ... please dont post the same thing half a dozen times in different threads! :blink:

#12 Neilwa

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Posted 07 April 2005 - 09:47 PM

HD ON ABC AND SBS IS CRAP AND THEY NEED TO KNOW NOW!!

Email your complaint direct to:

Jo Lindsay
ABC Transmission Public Relations

Advice.Reception@abc.net.au

Below is what I wrote - their reply - and my counter reply!
I may get an answer one day, but they must understand that the current HD image is so poor, IT IS NOT HIGH DEFINITION when it has such a SOFT FOCUS that it looks FUZZY and by all accounts (see http://www.dtvforum....showtopic=16581 ) it should not be classed as a true legal HD pixel rating if interpolation/interlacing is taking place! If I buy a 3Megapixel camera I want 3MP - not 1MP pretending to be 3!! HD should technically be superior to SD on a true pixel rating!


Email 31/3/2005 to ABC Transmission Complaints

I spoke with Troy on 1300139994 and he said to email so the problem can be addressed.

I have a Teac DV-B800 HD set top box and an Hitachi 42PD5000 HD plasma screen. When I turn on the ABC HD channel 20, I notice the picture quality is now very poor (fuzzy) compared to the SD channel 2 (which now appears sharper than the dedicated HD channel). It wasn't like this several weeks ago and I have since tried retuning the Teac STB but to no avail. The ABC HD picture used to be very very sharp and clear. Channel's 7, 9 and 10 all have very very sharp and clear HD channels. What has happened with the ABC HD signal???? Thanks for your help and time.


Reply from ABC

Thank you for your email.

The ABC has recently been required to move its high definition television service from the 1080 interlaced format to 576 progressive. Both formats meet the legislative requirements for digital television in Australia.

This change in format has been necessary to facilitate the introduction of ABC2, the ABC's second channel available to viewers like yourself with a digital receiver, as well as the digital audio streams DiG and DiG JAZZ, and the proposed ABC Electronic Programme Guide, which will appear on Channel 22 later this year.

Like all free to air broadcasters, the ABC is required to broadcast 1040 hours of high definition per year. However, we also have charter
obligations to provide programs of an educational nature, that promote the musical, dramatic and other performing arts, and that inform and entertain.

The ABC has taken a considered approach to this decision to introduce ABC2 and change the format of our high definition service, and it has been made to meet our competing editorial and technical requirements within the constraints of the digital bandwidth. Our high definition service continues to be delivered within the Australian standard of the format, however, by providing these additional services the ABC will also reinforce our charter obligations to the Australian audience.

I hope you understand the reasons the ABC has made this decision.

Yours sincerely,

Jo Lindsay
ABC Transmission Public Relations


MY REPLY BACK 'COS I DON'T LIKE NON-ANSWERS:

Dear Jo Lindsay,

Thank you for your email. However, it does not answer the main question I had concerning the fuzziness of the ABC HD signal.

I understand that the ABC has constraints and will need to transmit a lower signal count for HD, but why is the picture poorer than SD??

I have checked the picture quality of the ABC and SBS on both a HD STB and via a HD computer DTV card. The SD picture is perfect but both the HD pictures show poorly (e.g. fuzzier than SD). Channels 7, 9 and 10 all show perfectly in HD and SD. In particular, Channel 7 who also uses a lower HD signal count comes out crystal clear in HD.

So what's up with ABC and SBS?? I really want to get to the bottom of this issue.

Kind regards,


I AM STILL WAITING FOR A REPLY

#13 ChrisM

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Posted 07 April 2005 - 11:27 PM

Imagine a Lawyer arguing the 576P case in Court:

"Well your Honor, our client contends that the high definition standard does not actually require the broadcast picture to be of a higher image resolution than standard definition. In fact, it is perfectly legal for the HD signal to resolve less detail than the SD transmission when both the SD and HD transmissions originate from the same program source"

Judge: "But I thought HD was supposed to be sharper than SD, and anyway I though 576P was called enhanced definition"

"No, your Honor, we couldn't call it enhanced because that would be misleading. My client does not suggest that the resolution is enhanced in any way, it is simply reformatted to suit the legislative requirements, and that legislation requires us to call it HD, even though it is actually of a lower resolution than the original SD source."

Sounds pretty stupid, but it's true.

#14 gepm

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Posted 08 April 2005 - 07:58 AM

The problem is as I'm sure you will agree that the resolution is not increased


No I don't agree, becasue as I explained, real 576 50P (not deinterlaced 576i) does have higher resolution than 576i. There's a differance between progressive display scanning and progressive origination.

I do agree, however, that it's not a big enough resolution difference to have the same impact as real 720P/1080i/P HD, and so deserves the title ED.

<{POST_SNAPBACK}>


The quote above is true. 576p DOES NOT have more 'resolution' than 576i. Unless a program is shot on tape & 576p50, then it's a converted fudge. There are no 576p cameras, let alone production equipment. TV stations use converters to get 576p, however 576p will appear 'smoother' for those with average Plasmas/LCDs.

The first posting here is right on. GET RID OF 576p. Also 576p is not listed world wide any where as a world standard?????????????

#15 bytheway

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Posted 08 April 2005 - 03:10 PM

Hi everyone,

Sorry for multiple postings, it was my first visit to the forum and there were no posts under the High Definition Programs forum so I thought no one would check it.

The UK has recently released their HDTV standards and as with the rest of the world it is 720p and 1080i. I have a few questions:

1. Why 1080i and not 1080p? Do their HD cameras record an interlaced or progressive image? In any case, their deinterlacers would be better than those in our consumer products no matter how high end. Is it a bandwidth problem?

2. Are projectors, LCD and plasma progressive only displays ie if they receive an interlaced input they MUST convert to progressive?

3. Are there any DVD players that output upscaled video (720p or 1080i) over component cables?

4. The new high definition DVD successors will use outputs that current displays are not specified to accept, the Blu-Ray disc association states these outputs will be supported:
- 1920 x 1080 HD (50i, 60i and 24p)
- 1280 x 720 HD (50p, 60p and 24p)
- 720 x 576/480 SD (50i or 60i)
How will current displays cope with these signals or will the player need to convert these to eg 720p or 1080i?

Thanks, Ben

#16 Santa

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Posted 08 April 2005 - 03:17 PM

Hi everyone,

Sorry for multiple postings, it was my first visit to the forum and there were no posts under the High Definition Programs forum so I thought no one would check it.

The UK has recently released their HDTV standards and as with the rest of the world it is 720p and 1080i.  I have a few questions:

1.  Why 1080i and not 1080p?  Do their HD cameras record an interlaced or progressive image?  In any case, their deinterlacers would be better than those in our consumer products no matter how high end.  Is it a bandwidth problem?

1080p is too high bandwith (well, if you want to preserve the quality)

2.  Are projectors, LCD and plasma progressive only displays ie if they receive an interlaced input they MUST convert to progressive?

DLP, LCD and plasma convert to progressive (apart, perhaps from the pseuo-interlace plasma, whatever its called - name slipped my memory)

3.  Are there any DVD players that output upscaled video (720p or 1080i) over component cables?

Probably the famous momitsu, some denons etc

4.  The new high definition DVD successors will use outputs that current displays are not specified to accept, the Blu-Ray disc association states these outputs will be supported:
- 1920 x 1080 HD (50i, 60i and 24p)
- 1280 x 720 HD (50p, 60p and 24p)
- 720 x 576/480 SD (50i or 60i)
How will current displays cope with these signals or will the player need to convert these to eg 720p or 1080i?

Thanks, Ben

<{POST_SNAPBACK}>

Those outputs are supported currently, btw {1080i, 720p and 576i}!

#17 BlueDusk

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Posted 08 April 2005 - 03:19 PM

Most American primetime shows transmitted in 1080i can be viewed in 1080p@25hz w/out interlacing artifacts. I think the only way you can view it this way is through a computer though.

#18 nexx

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Posted 08 April 2005 - 04:21 PM

Most American primetime shows transmitted in 1080i can be viewed in 1080p@25hz w/out interlacing artifacts. I think the only way you can view it this way is through a computer though.

<{POST_SNAPBACK}>


That's because they are shot on film. Same with most movies shown here...looks damn good too.

#19 bytheway

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Posted 08 April 2005 - 07:50 PM

DLP, LCD and plasma convert to progressive (apart, perhaps from the pseuo-interlace plasma, whatever its called - name slipped my memory)

What method do they use: weave, bob or motion adaptive? Am I right that in most cases an external deinterlacer in the source or video processor will usually do a better job

Those outputs are supported currently, btw {1080i, 720p and 576i}!

1080 24p is not supported, and as most movies are shot on film, this will be the format used, so how will current displays support it?

#20 BlueDusk

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Posted 08 April 2005 - 08:14 PM

Most American primetime shows transmitted in 1080i can be viewed in 1080p@25hz w/out interlacing artifacts. I think the only way you can view it this way is through a computer though.

<{POST_SNAPBACK}>


That's because they are shot on film. Same with most movies shown here...looks damn good too.

<{POST_SNAPBACK}>


Yup, either film or a digital video camera capable of doing 24/25p (I think The 4400 was done this way?).

#21 rochford

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Posted 08 April 2005 - 08:22 PM

Yup, either film or a digital video camera capable of doing 24/25p (I think The 4400 was done this way?).

<{POST_SNAPBACK}>

Not sure about The 4400 (IMDB doesn't have any tech specs), but this is definitely the right way to do 1080@50i - it is then capable of being 'cleanly' deinterlaced for progressive display, and 'degrades' gracefully to 1080@50p (albeit at half the possible frame rate).

- Miles.

#22 Morn

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Posted 08 April 2005 - 10:57 PM

actually, there is a difference:

http://img94.exs.cx/my.php?loc=img94ℑ=starship43kg.gif

http://img207.exs.cx...tarship35qn.gif

http://img207.exs.cx...tarship29pd.gif

http://img203.exs.cx...tarship12iv.gif

<{POST_SNAPBACK}>


Well which is which? :blink:

#23 DavoNogo

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Posted 09 April 2005 - 12:49 PM

actually, there is a difference:

http://img94.exs.cx/my.php?loc=img94ℑ=starship43kg.gif

http://img207.exs.cx...tarship35qn.gif

http://img207.exs.cx...tarship29pd.gif

http://img203.exs.cx...tarship12iv.gif

<{POST_SNAPBACK}>


Well which is which? :blink:

<{POST_SNAPBACK}>


if you haven't opened them up yet, they're animated gif's set to alternate between the two every half a second or so

the one with the high definition logo on the bottom right corner of each shot is the one that's high definition (sorry.. "enhanced definition" as they say in this forum)

and the one without the logo is the dvd

i got lazy and couldn't be bothered labelling each screenshot with either a HDTV or DVD logo for 8 different shots

#24 Morn

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Posted 09 April 2005 - 06:25 PM

Interesting, the ED channels are clearly higher in definition. I wonder if ED really is that much better or it was crappy dvd mastering. One presumes they would have ot master it again especially for the HD broadcast. Another problem is that many DVD's are reencoded from the 480p US dvd's. So try do this again, comparing 7's SD and HD transmission. :blink:

#25 DavoNogo

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Posted 09 April 2005 - 07:14 PM

right, anyone have the SD transmission of this? so we can compare? cuz i only record the HD channels, using DVR-MS (not enough hdd space for full .ts)