is 540p "true" High Definition?

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scatpack

Limp Gawd
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If a 16:9 monitor supports 1080i and 540p is it a "true" high def? Or does it need to support 720p to be "true"?
 
No, not really. The HDTV formats are 720p, 1080i, and 1080p.

http://electronics.howstuffworks.com/hdtv1.htm

...not that it matters. There isn't an official standard, to my knowledge. You can call it HD if you feel better doing so. "High definition" is a vague and relative term, nothing more.
 
540P us not HD, there is a massive thread discussing this on the AVS forums. Basically its coming out that 720P sets are taking a 1080i stream and converting it to 540P for the picture.
A large group is considering a class action law suit because they feel they have been lied to. The processing power to convert a 1080i -> 540P is much less than converting 1080i->720P.
 
NugeRules said:
I thought 480p was EDTV :confused:
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Nah....480p is standard U.S. resolution, just with progressive scan...the "P" only represents progressive scan, which draws the whole image in one go rather than every other line. It displays a brighter, not necessarily clearer, but more "veiwable" picture. This is reason for many people choosing 720p over 1080i...1080i is flickery (tons of scan lines) as to where 720p is still high def (and still looks great) and is progressive scan. 720 and above is high definition.
 
I personally like 720p better... but it is all taste. I don't even prefer it because of direct experience either. I just detest the idea of interlacing as a concept. :)
 
Exactly.

- Less than 480p is SDTV
- Less than 720p is EDTV
- 720p and up is HDTV

Code: 
<<----480i----|----480p----|----540p----|----720p----|----1080i---->>
<<====SDTV====|==========EDTV===========|==========HDTV============>>
 
i prefer 720p as well. hopefully 1080p will become widely supproted one day.
 
There are a few new 1080p sets, well they were introduced but I'm not sure if anyone can really buy them yet.

Anyone know if the next generation of dvd (hd-dvd or blu-ray) will be able to handle 1080p, or will it just be a 720, 1080i thing.
 
Anyone know if the next generation of dvd (hd-dvd or blu-ray) will be able to handle 1080p, or will it just be a 720, 1080i thing.
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Sony developed 1080p and Blu-ray was definitely capable and HD-DVD most likely could have supported it but Toshiba never would have gone with 1080p. But now with both groups merging their tech, 1080p as a standard may actually emerge and that would be our only hope because you won't see it through broadcast in a very long time.

There are 18 ASCT Accepted formats:

HDTV
1080p 1080x1920 16:9 Progressive 24
1080p 1080x1920 16:9 Progressive 30
1080i 1080x1920 16:9 Interlaced 30
720p 720x1280 16:9 Progressive 24
720p 720x1280 16:9 Progressive 30
720p 720x1280 16:9 Progressive 60

]EDTV
480p 480x704 16:9 Progressive 24
480p 480x704 16:9 Progressive 30
480p 480x704 16:9 Progressive 60
480p 480x704 4:3 Progressive 24
480p 480x704 4:3 Progressive 30
480p 480x704 4:3 Progressive 60
480p 480x640 4:3 Progressive 24
480p 480x640 4:3 Progressive 30
480p 480x640 4:3 Progressive 60

SDTV
480i 480x704 16:9 Interlaced 30
480i 480x704 4:3 Interlaced 30
480i 480x640 4:3 Interlaced 30
 
How did Sony develop 1080p if it was an ATSC standard?

BTW Sharp has been selling 40 and 46inch 1080p LCD TVs for a while now. The new sets are 3rd gen DLP-chip based sets which, with some luck, will be a lot cheaper than Sharp's offerings.
 
The problem with HD is there are two camps. Some networks have chosen 720p standard while others have chosen 1080i. 720p is supposed to be better at displaying sports. Unfortunately, TVs are the same thing, they are either 720p or 1080i. As mentioned in this thread, the TVs have to convert the images to display on the screen if its in a different format. LCDs and DLPs pretty much are 720p, except the previously mentioned 45" Sharp Aquos, while CRTs are 1080i.
I'm looking to get an HD TV by the end of the year. Unfortunely it won't be a flat panel. Sticking with the tried and true CRT. CRTs still offer a better picture (no flames please)and the price is much better.
Hres a link to the article concerning the 720p conversion to 1080i.

http://www.hdblog.net/index.php/2005/05/02/when-is-720p-not-720p/
 
dualityim said:
How did Sony develop 1080p if it was an ATSC standard?
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Sony developed the tech, ATSC adopted it as the standard. They don't just make up numbers and say this is what you have to do. Someone has to design the working models first.

1080p/24 was developed by sony to replace 35mm film for feature films.
 
1920 by 540 is still a pretty godamn nice picture.

Its worth noting that the majority of 1080i content you see is 1440x1080i. Not 1920. many high-end cameras dont bother. Why? Its not necessary. the 1080 spec is, in my opinion, an abortion.

Its way too big. Broadcasters could never hope to broadcast 1920x1080p60 with their current amount of bandwidth (19.39mbits/sec), and their amount of bandwidth wont change. After everyone gets their set-top boxes and such, they wont be able to change the encoding (mpeg2) to something more efficient.

At least, they couldn't broadcast 1080p60 RIGHT. most broadcasters multiplex other channels into their DTV streams, and this will only become more common.

1920x1080 bandwidth is wasted, because like I said about cameras above, no one can tell the difference between 1440 and 1920. I believe that even Sonys high-end videotape format, HDCAM-SR, only supports 1440. 1080i Interlacing looks like ass.

1280x720p60 is the perfect solution for broadcasters today. It doesnt require the whole DTV steam so space is available for multiplexed streams, looks awesome with 60FPS, and is high (enough) resolution.

The reason some of the networks have went with 1080i is their stated desire to get to 1080p. This isn't happening for a while, and I dont believe it'll happen for a long while.

One GOOD thing for 1080 is film. It's a good match, and there is a 1080p24 spec created by sony.
 
CrimandEvil said:
540p is a PAL res.
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Actually there were 18 digital formats ratified for broadcast use in the US, 540P was in fact listed as the “starting resolution” of High def. A few stations even used it for a bit. Now most (HD) broadcast is 1080i and 720p.
 
i for one still think 1080i was a big waste.

whats the point of creating another interlaced res, when everyone else is moving towards the progressive signal? now the market is flooded with all these crappy 480p/1080i "HDTV's" that dont support 720p. its funny that 2 years ago i saw Sharp displaying their 50' 1080p LCD at CES.

the tech is there, why wont they use it?

btw,
1080p 1080x1920 16:9 Progressive 30
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is that 30 the refresh rate? I dont see how you can have a progressive signal if its not running at 60hz. something is odd about that standard. anyone?
 
is that 30 the refresh rate? I dont see how you can have a progressive signal if its not running at 60hz. something is odd about that standard. anyone?
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The 1080p ATSC defined is not the 1080p 60fps that is usually referred to. ATSC's 1080p is much more like 1080i transmitted in a non-interlaced manner, with two fields combined into one to make 30fps.
 
right. backwards compatibility will continue to be an issue. 720p60 is actually 59.94 fps. I forget the exact number. 1080p30 will be 29.97. Same as DV drop-frame.
 
Methodical said:
right. backwards compatibility will continue to be an issue. 720p60 is actually 59.94 fps. I forget the exact number. 1080p30 will be 29.97. Same as DV drop-frame.
Click to expand...

So you can tell a 0.1% change in frame rate =P
 
Methodical

one issue that you brought to light but forgot to include for 720 is bandwidth.

720p take up more bandwidth up than 1080i. If i remember it is about 1/3 more bandwidth required for 720p broadcast than 1080i. Now here is a dilema that the cable/satellite companies have (not really as they want to squeeze as many DTV streams they can per transponder).

A cable/satellite provider will want to conserve bandwidth so they can eek out more channels. Of course the user wants quality coming dow..... who the hell am i kidding. The people that actually care are in the minority. The rest of the people. They eat what they get fed and leave it at that. So if it is craptacular 1080i with mpeg artifacts all over the place. As long as they see it is 1080i. They will not bitch.
 
figgie said:
Methodical

one issue that you brought to light but forgot to include for 720 is bandwidth.

720p take up more bandwidth up than 1080i. If i remember it is about 1/3 more bandwidth required for 720p broadcast than 1080i. Now here is a dilema that the cable/satellite companies have (not really as they want to squeeze as many DTV streams they can per transponder).

A cable/satellite provider will want to conserve bandwidth so they can eek out more channels. Of course the user wants quality coming dow..... who the hell am i kidding. The people that actually care are in the minority. The rest of the people. They eat what they get fed and leave it at that. So if it is craptacular 1080i with mpeg artifacts all over the place. As long as they see it is 1080i. They will not bitch.
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Not true. 1080i is actually technically 1920x1080i. It also comes in at 60 Hz. Scale it to 1920x540p effectively to square away refresh rate for 720p @ 30 Hz then you get 12.5% more bandwidth for 1080i. 1080i has the ability to produce a superior static image over 720p (things like LNWDL). However for action movies...it is teh suck.

-tReP
 
Trepidati0n said:
Not true. 1080i is actually technically 1920x1080i. It also comes in at 60 Hz. Scale it to 1920x540p effectively to square away refresh rate for 720p @ 30 Hz then you get 12.5% more bandwidth for 1080i. 1080i has the ability to produce a superior static image over 720p (things like LNWDL). However for action movies...it is teh suck.

-tReP
Click to expand...

apparently you are not reading.

the signal that we get via HD (namely on DirectTV and Dish) is NOT 1920x1080i but is in FACT 1440x1080i. Do the math once more. 720p needs more bandwidth at those compressed rate.
 
figgie said:
apparently you are not reading.

the signal that we get via HD (namely on DirectTV and Dish) is NOT 1920x1080i but is in FACT 1440x1080i. Do the math once more. 720p needs more bandwidth at those compressed rate.
Click to expand...


Thats because you are getting the shaft with DTV, they are transmiting whats called HD-Lite to save bandwidth and fit more channels on the same transponder.

DTV does NOT broadcast in full HD
 
Trepidati0n said:
So you can tell a 0.1% change in frame rate =P
Click to expand...

Its a pretty big issue actually, with sound/video sync. a pain in the ass as it is, doesn't need further complication.

1080 requires slightly more bandwidth than 720... but as someone else mentioned DirectTV is 1440x1080i (news to me).

almost all the 1080 content you see today is 1440x1080i. even if it is being received at the 1920x1080i resolution. Its a matter of equipment.

I work at a fox affiliate, and fox actually has a really super-badass distribution system for HD that about to go completely online with every affiliate. They have four transponders. Currently, the datarate is 55mbits/sec. Pretty high. They are about to jack it up to 73mbits a sec by upping the symbol rate and dropping the forward error correction rate. We have a fucking huge bad-ass dish fox installed just to get a decent signal (in alaska). our signal is marginal. Anyway, 73mbit x 4 transponders for the fox network, fox sends everything in HD....

The really cool thing about Fox is the equipment they gave us to manage the streams... Typically, when you need to change anything in mpeg it must be converted to baseband (decompressed), changed, and recompressed. We've got a little unit called a terayon bp 5100. Without decompressing to baseband, it can change the bitrate of streams, key information over streams (logos for station branding and such), and most amazingly - switch between streams without taking a hit.

bitrate changing ("grooming") is pretty freakin sweet. The terayon can accept a multiplexed ASI signal (say, two or three mpeg2 streams in a 19.39mbit total size), change the bitrate of any or all streams, change the stream identification data, etc ,etc. way cool.

When you think about the fact that a stream consists of closed captioning, PSIP (guide/program information), tons of extra information, and all the other stuff that goes on... its a lot of work. The stream switching is the most amazing though ("splicing"). we receive short-GOP mpeg2....(i think? might be long GOP)... the fact is, you cant switch during anything but a B-frame (I and P frames are dependent on surrounding frames). The terayon switches during any frame without taking a hit, without decompressing.

And its 1U in size.

73mbit x 4 isn't actually as much as it sounds, i should explain. one channel is for news distribution (for affiliates to use). One channel is for misc. things like promos and stuff, and two channels for the "main" feeds. One is a backup. Completely redundant. Primetime is big bucks. I believe fox currently sends down SD 4:3, SD 16:9, and of course the HD feed... at the same time, on the same transponder. redundant link is the same.

Normal HD distribution costs a lot more because as much bandwidth as possible must be sent up, to counter the quality losses at the station for decompressing/recompressing.

back on tangent... the thing with 1440x1080i is, it isn't a standard. Its a hack. Things will get better though. Hopefully (probably YEARS in the future) h.264 or something similar will get adopted and increase compression efficiency.
 
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