[Quidam67]

Hi all.


At some point I plan to purchase a PS3, mainly because of it's ability to play back blu ray, and it's potential to deliver great games in the future (I already own 2 360's).


Given my current knowledge about how existing DVD's work, I have a question or two about the Hi Def format that I'm hoping someone might be able to help me understand better.


So in no particular order:


For NTSC and PAL, we have 60 and 50hz respectively. I'm assuming the same holds true for 720p and 1080i/p signals? If this is so:


For Hi Def movies, are the same solutions required/used to map a 48hz film to a 60 or 50hz display device? (eg 3:2 pull down; 4% speed up or 2:2:2:2:2:2:2:2:2:2::2:3 pull-down)


How are Hi Def movies stored on Blu Ray? Are they stored in the native 24 fps? Or is it more like DVD, where they are they stored as interlaced fields that the Blu Ray player puts back together (eg. progressive scan)?


What does it mean when a Blu Ray (or HD DVD player) is advertised as being able to handle 1080p/24, as versus 1080p/60? I got the impression that 1080p/24 is better, but surely this still requires pull-down manipulation etc in order to be played on the small screen, so why is it better?


Many thanks

b

 

[CKNA]

No PAL or NTSC for Blu-ray. All films are stored at 24fps everywhere thus no speed up. 2:3 pulldown is used and newer displays can accept 24fps and display it at 72Hz or 120Hz. Of course player has to be able to output 24fps. Some do and some don't.

 

[Quidam67]



Quote:
Originally Posted by CKNA /forum/post/0


No PAL or NTSC for Blu-ray. All films are stored at 24fps everywhere thus no speed up. 2:3 pulldown is used and newer displays can accept 24fps and display it at 72Hz or 120Hz. Of course player has to be able to output 24fps. Some do and some don't.

OK, It's starting to make sense. 720p 1080i/p is universal. So if I play a movie at 720p on my hi def TV it is likely to be at 72hz -I know the TV is capable of that (via VGA).


So what do they mean when they say that the PS3 is 1080p/60? by the sounds of it, it means it takes a 24fps signal and performs pull-down on it so my TV would run 720p/1080i/p at 60hz (meaning 3:2 judder) rather than a smooth 3:3 72hz.


Thanks.

b

 

[YellowCows]

Film is shot at a framerate of 24 frames per second. ALL HD movies from all studios worldwide encode discs in 1080p/24 for both Blu-ray and HD-DVD.


PAL/NTSC is irrelevant - it only applies to SD formats (DVD, Laser, VHS etc.).


Frequency is a separate issue. The 60Hz vs. 50Hz discrepancies are related to the voltage specifications of different regions. For example, in North America, the voltage is 120V rated @ 60Hz. In Europe (and much of the rest of the world), it is 240v @ 50Hz; Japan's electricty is rated at 110V @60Hz. Because Pal and NTSC are delineated along the same regional variations as voltage, people often think that PAL means 50Hz and NTSC means 60Hz. That is not so. PAL can be rated at 60Hz, in fact nearly every TV model sold in the UK, Europe and the Middle East/Africa have a 'PAL 60' mode. HD broadcasts in Europe are either 1080i/50 or 720p/50, in 60Hz regions, they are rated at 60Hz.


As the HD discs are encoded at the framerate of the source material (the film), i.e. 24fps, and being that most displays on the market can neither accept nor display a 1080p/24 input, the players themselves (whether Blu-ray or HD-DVD) all perform internal frame rate conversion, to output 1080p (or 1080i, or 720p) at 60Hz or 50Hz (depending on the model's spec). It has nothing to do with PAL or NTSC.


Hope that helps.

 

[wildfire99]

So why are people complaining about PAL speedup on the audio with imported HDM discs?

 

[CKNA]



Quote:
Originally Posted by wildfire99 /forum/post/0


So why are people complaining about PAL speedup on the audio with imported HDM discs?

What are HDM discs? Do you mean some HD DVD tiltles form Studio Canal? These were screwed up at mastering.

 

[CKNA]



Quote:
Originally Posted by YellowCows /forum/post/0


Film is shot at a framerate of 24 frames per second. ALL HD movies from all studios worldwide encode discs in 1080p/24 for both Blu-ray and HD-DVD.


PAL/NTSC is irrelevant - it only applies to SD formats (DVD, Laser, VHS etc.).


Frequency is a separate issue. The 60Hz vs. 50Hz discrepancies are related to the voltage specifications of different regions. For example, in North America, the voltage is 120V rated @ 60Hz. In Europe (and much of the rest of the world), it is 240v @ 50Hz; Japan's electricty is rated at 110V @60Hz. Because Pal and NTSC are delineated along the same regional variations as voltage, people often think that PAL means 50Hz and NTSC means 60Hz. That is not so. PAL can be rated at 60Hz, in fact nearly every TV model sold in the UK, Europe and the Middle East/Africa have a 'PAL 60' mode. HD broadcasts in Europe are either 1080i/50 or 720p/50, in 60Hz regions, they are rated at 60Hz.


As the HD discs are encoded at the framerate of the source material (the film), i.e. 24fps, and being that most displays on the market can neither accept nor display a 1080p/24 input, the players themselves (whether Blu-ray or HD-DVD) all perform internal frame rate conversion, to output 1080p (or 1080i, or 720p) at 60Hz or 50Hz (depending on the model's spec). It has nothing to do with PAL or NTSC.


Hope that helps.

Technically PAL and NTSC are not even part of DVD. DVD is digital. PAL and NTSC refer to composite analog video. FYI Japan voltage is 100V at 50Hz and 60Hz. Northern part of Japan uses 60Hz, and southern part uses 50Hz.

 

[YellowCows]



Quote:
Originally Posted by CKNA /forum/post/0


Technically PAL and NTSC are not even part of DVD. DVD is digital. PAL and NTSC refer to composite analog video. FYI Japan voltage is 100V at 50Hz and 60Hz. Northern part of Japan uses 60Hz, and southern part uses 50Hz.

Actually, PAL when used in reference to DVD relates to everything but color spectrum encoding, unlike analog PAL. This is the same as when PAL is used to refer to DVB broadcasts (digital SD broadcasts) in PAL regions. It designates 576i (625-line picture) at 25 fields/50 frames per second of interlaced video. NTSC, however, does refer to the color encoding with regards to DVD.


I stand corrected about Japan's voltage.

 

[wildfire99]



Quote:
Originally Posted by CKNA /forum/post/0


What are HDM discs? Do you mean some HD DVD tiltles form Studio Canal? These were screwed up at mastering.

It's the new term for high-definition media!

I mean HD-DVD and/or Blu-Ray. I thought that the move to high-definition formats would end the PAL/NTSC catfight, but then I heard about people importing movies (like Total Recall) that had audio issues due to a speed-up. (24p->25p)


That would be Studio Canal though. So at least HDM is supposed to work. Thanks.

 

[Quidam67]



Quote:
Originally Posted by YellowCows /forum/post/0


Film is shot at a framerate of 24 frames per second. ALL HD movies from all studios worldwide encode discs in 1080p/24 for both Blu-ray and HD-DVD.


PAL/NTSC is irrelevant - it only applies to SD formats (DVD, Laser, VHS etc.).


Frequency is a separate issue. The 60Hz vs. 50Hz discrepancies are related to the voltage specifications of different regions. For example, in North America, the voltage is 120V rated @ 60Hz. In Europe (and much of the rest of the world), it is 240v @ 50Hz; Japan's electricty is rated at 110V @60Hz. Because Pal and NTSC are delineated along the same regional variations as voltage, people often think that PAL means 50Hz and NTSC means 60Hz. That is not so. PAL can be rated at 60Hz, in fact nearly every TV model sold in the UK, Europe and the Middle East/Africa have a 'PAL 60' mode. HD broadcasts in Europe are either 1080i/50 or 720p/50, in 60Hz regions, they are rated at 60Hz.


As the HD discs are encoded at the framerate of the source material (the film), i.e. 24fps, and being that most displays on the market can neither accept nor display a 1080p/24 input, the players themselves (whether Blu-ray or HD-DVD) all perform internal frame rate conversion, to output 1080p (or 1080i, or 720p) at 60Hz or 50Hz (depending on the model's spec). It has nothing to do with PAL or NTSC.


Hope that helps.

Yes, very much so, like more pieces of the jigsaw puzzle. Since I'm in a PAL region, I'll be buying a PAL PS3, so I assume it will take the 1080p/24 and convert it to 50hz -which is a shame, since my TV can handle 72hz (according to the PC mode specifications). And if it's going to 50hz, without temporal speedup, then it must surely do the 2:2:2:2:2:2:2:2:2:2::2:3 pull-down thing.


So am I right in concluding that the issue/requirement for pull-down or speed-up remains alive and well for the Hi Def era? It seems unfortunate that the new formats/hardware could not have put this issue to bed. I mean, it seems to me modern TV's can handle higher refresh rates (like 72hz) and HD/Blu Ray players should be able to detect/leverage off the features of the TV and only perform judder-inducing pull-down when they need to.

 

[gooki]



Quote:
I mean HD-DVD and/or Blu-Ray. I thought that the move to high-definition formats would end the PAL/NTSC catfight, but then I heard about people importing movies (like Total Recall) that had audio issues due to a speed-up. (24p->25p)


That would be Studio Canal though. So at least HDM is supposed to work. Thanks.

I believe what happened there, was the video master they had was 24fps, but their master audio files were 25fps. When they preformed the 25fps to 24fps audio adjustment the pitch didn't revert back to it's original pitch, most likely due to improved methods of pitch adjustment in audio processing tools.


Do be aware it's very minor and i'd be surprised if you can pick it up.


Hewever for non film HD sources there are still issues such as 25p/50i which some countries in europe use vs the 30p/60i which japan/usa use exclusively.

 

[CKNA]



Quote:
Originally Posted by Quidam67 /forum/post/0


Yes, very much so, like more pieces of the jigsaw puzzle. Since I'm in a PAL region, I'll be buying a PAL PS3, so I assume it will take the 1080p/24 and convert it to 50hz -which is a shame, since my TV can handle 72hz (according to the PC mode specifications). And if it's going to 50hz, without temporal speedup, then it must surely do the 2:2:2:2:2:2:2:2:2:2::2:3 pull-down thing.


So am I right in concluding that the issue/requirement for pull-down or speed-up remains alive and well for the Hi Def era? It seems unfortunate that the new formats/hardware could not have put this issue to bed. I mean, it seems to me modern TV's can handle higher refresh rates (like 72hz) and HD/Blu Ray players should be able to detect/leverage off the features of the TV and only perform judder-inducing pull-down when they need to.

Your PS3 will play Blu-ray disks at 60Hz. Speed up is done during mastering. Players can't speed up disks as audio would have to resampled on the fly.

 

[CKNA]



Quote:
Originally Posted by YellowCows /forum/post/0


Actually, PAL when used in reference to DVD relates to everything but color spectrum encoding, unlike analog PAL. This is the same as when PAL is used to refer to DVB broadcasts (digital SD broadcasts) in PAL regions. It designates 576i (625-line picture) at 25 fields/50 frames per second of interlaced video. NTSC, however, does refer to the color encoding with regards to DVD.


I stand corrected about Japan's voltage.

I am not sure what you are saying but color on DVD's for PAL and NTSC is encoded exactly the same way. DVD's use component video, so there is no color encoding as was used in analog video. The only difference is number of lines and refresh rate.

 

[YellowCows]



Quote:
Originally Posted by CKNA /forum/post/0


I am not sure what you are saying but color on DVD's for PAL and NTSC is encoded exactly the same way. DVD's use component video, so there is no color encoding as was used in analog video. The only difference is number of lines and refresh rate.

Yes, Mpeg2 video used in DVD's is encoded as YUV - with PAL designating 625-line and NTSC 525-line picture. CVBS encoding does not relate in this instance. Also, being that YUV-colorspace is used universally, there is no difference in colorspace, unlike with analog. What I am referring to is the fact that the phase issues with NTSC are still prevalent with analog output from DVD, necessating the need for 'tint' control/adjustment carried over from analog NTSC, which PAL does not suffer from. Further, the framrate conversion needed for 3:2 pulldown due to the 30fps/60 discrepancy, as compared to the simple speedup (2:2 pullup) from 24 to 25fps with regards to PAL.


But this is all old news, HD formats eliminate these issues - that's the bottom line.

 

[sneals2000]

YUV is incorrect terminology - U and V are specific colour difference signals weighted for PAL encoding. If you are talking about digital component signals then YCrCb is the correct terminology - something PC codec people seem ignorant of...

 

[sneals2000]



Quote:
Originally Posted by Quidam67 /forum/post/0



So in no particular order:


For NTSC and PAL, we have 60 and 50hz respectively. I'm assuming the same holds true for 720p and 1080i/p signals? If this is so:

Yes - and no.


1080/50i (and to a lesser degree 720/50p) are the HD BROADCAST formats used for transmission of HD in Europe, Australia and other 50Hz HD regions. (i.e. those that previously used 50Hz PAL or SECAM) Additionally there is an HD video production standard in 1080/25p (and 720/25p) which is used in production where previously 25fps film may have been used.


1080/60i and 720/60p are the HD BROADCAST formats used for transmission of HD in North America, Japan and Korea, and other 60z regions. (i.e. those that previously used 60Hz NTSC or possibly 60Hz PAL in the case of Brazil) Additionally there are HD production standards of 1080/24p (and 720/24p) as well as the less-widespread 1080/30p (and 720/30p) which are used in production where previously 24fps film may have been used.


Additionally there are 1080/24p, 1080/50p and 1080/60p HD INTERCONNECT standards, that can be used to connect sources to displays via Component, VGA and HDMI/DVI cabling etc.

Quote:
For Hi Def movies, are the same solutions required/used to map a 48hz film to a 60 or 50hz display device? (eg 3:2 pull down; 4% speed up or 2:2:2:2:2:2:2:2:2:2::2:3 pull-down)

For BROADCAST - Yes.


In 50Hz territories, movies shot 24fps are BROADCAST at 1080/50i (or 720/50p) with 2:2 and 4% speed-up mainly. Original TV content shot on film or HD video with "a film look" is shot at 25p and broadcast in 1080/50i (or 720/50p) with no speed-up.


In 60Hz territories, movies shot at 24fps are BROADCAST at 1080/60i or 720/60p with 3:2 and no speed-up. Original TV content shot on film or HD video is usually shot at 24fps and with 3:2 pull-down and no speed up.


HOWEVER - things are different for HD DVD and BluRay. This is because most displays sold in 50Hz territories also support 60Hz video - in fact in Europe this is a demand to be licensed "HD Ready" - the Europe-wide HD licensing scheme.


This means that most (so far all?) 24fps movie material released in both 50 and 60Hz regions has been released as 24p "on disc". This can be output either in 1080/60i with 3:2 field pull-down, 1080/60p or 720/60p with 3:2 frame repetition - with some players and displays additionally supporting 1080/24p connections, with display refresh rates potentially at 48, 72, 96 or 120Hz. The 1080/24p material on-disc is NOT converted to 1080/50i or 1080/50p (or 720/50p)


On these discs a lot of the extras are still 480/60i - but again most 50Hz displays will accept these (and all EU "HD Ready" displays will)


My understanding is that 1080/60i and 1080/50i, 720/60p and 720/50p are all also valid HD-DVD and BluRay standards - though I'm not sure that 1080/25p is.

Quote:
How are Hi Def movies stored on Blu Ray? Are they stored in the native 24 fps? Or is it more like DVD, where they are they stored as interlaced fields that the Blu Ray player puts back together (eg. progressive scan)?

BluRay stores 1080/24p natively. I believe HD DVD does something slightly different to BluRay - but can equally cope with generating a 1080/24p output.


Some players cheat and generate a 1080/60i signal internally which is then de-interlaced back to 1080/24p.


The PS3 currently outputs 24p material at 60Hz - and doesn't offer 24p output - though this may come with a future update.

Quote:
What does it mean when a Blu Ray (or HD DVD player) is advertised as being able to handle 1080p/24, as versus 1080p/60? I got the impression that 1080p/24 is better, but surely this still requires pull-down manipulation etc in order to be played on the small screen, so why is it better?

24p output is only a benefit over 60p output if you have a display capable of displaying at a multiple of 24Hz - say 72Hz or 120Hz - as in doing so you remove the 3:2 cadence judder inherent in 60Hz rendition of 24p material, where one film frame is displayed for longer than the next, un-naturally weighting it. In Europe, where 2:2 cadence with speed up is more common, we're not used to this 3:2 judder - and it really sticks out the first time you see it - particularly on linear pans etc.


If you haven't got a display that will cope properly with 24p (i.e. not convert it back to 60Hz) - then there is no benefit over 60p interconnection AIUI.

 

[sneals2000]



Quote:
Originally Posted by YellowCows /forum/post/0


Actually, PAL when used in reference to DVD relates to everything but color spectrum encoding, unlike analog PAL.

"PAL" in this context, when used to describe DVDs, is a sloppy short-hand for 50Hz. Although it is in widespread use it doesn't make it correct.


PAL = Phase Alternate Lines / Phase Alternating Lines - which is a precise definition of the way the chroma subcarrier alternates phase on a line-by-line basis to reduce the visibility of phase errors (which are mapped to saturation changes in PAL, rathe than hue changes as in NTSC)


Given that there are both 50 and 60Hz versions of PAL - as Brazil uses 525/60 with PAL (aka PAL-M) - it is a particularly poor way of using it.

Quote:
This is the same as when PAL is used to refer to DVB broadcasts (digital SD broadcasts) in PAL regions. It designates 576i (625-line picture) at 25 fields/50 frames per second of interlaced video.

I've never heard "PAL" used to describe DVB broadcasts in 50Hz territories. (And don't forget 50Hz DVB is extensively used in SECAM regions as well, not just PAL ones...)

Quote:
NTSC, however, does refer to the color encoding with regards to DVD.

NTSC, unlike PAL, defines not just a chroma standard, but also a line standard, so has more relevance to DVD, but this is semantics.


Describing any non-composite (or non-S-video) signal as "PAL" is just incorrect and sloppy. Just because the DVD labels do this doesn't make it right.


You will find most people in the industry refer to signals, territories etc. as 50Hz or 60Hz, as it is far less ambiguous, and works for HD, Digital Component etc. as well as composite.

 

[sneals2000]



Quote:
Originally Posted by YellowCows /forum/post/0


Japan's electricty is rated at 110V @60Hz.

Nope - Japan is 100V and the country is split between 50Hz and 60Hz regions, along roughly an East / West split.


Tokyo is in a 50Hz region - and if you've ever seen Japanese 60Hz video stuff shot at night in Tokyo you see 10Hz lighting flicker on discharge lights...

 

[YellowCows]

Sneals2000 - seriously, chill out. You seem on a personal mission to discredit over and above correction and semantics.


I shall resist the urge to argue with you (though I am tempted), as it would further hijack this thread, and I apologize for any offence caused to your delicate sensibilities by the use of common shorthand (e.g. YUV vs YCrCb, which I am aware of, thanks). Yes, we know what PAL stands for. Many of us know what it defines. We also know how it is commonly used, sloppy or not - take it up with the studios who label DVDs PAL or NTSC. FYI, 625-line interlaced video at 25fps/50Hz is commonly referred to and recognized as PAL, (even though PAL was developed as an analog broadcast format) whether you accept that or not. The same is true of NTSC and 525-lines, etc.


As for Japan, please read the posts through - the voltage issue was corrected before your helpful and pleasant diatribe.


There is a way of getting your point across without resorting to needless hostility or condescension. I think you'll find that can be a two-way street.

 

[sneals2000]



Quote:
Originally Posted by YellowCows /forum/post/0


Sneals2000 - seriously, chill out. You seem on a personal mission to discredit over and above correction and semantics.


I shall resist the urge to argue with you (though I am tempted), as it would further hijack this thread, and I apologize for any offence caused to your delicate sensibilities by the use of common shorthand (e.g. YUV vs YCrCb, which I am aware of, thanks). Yes, we know what PAL stands for. Many of us know what it defines. We also know how it is commonly used, sloppy or not - take it up with the studios who label DVDs PAL or NTSC. FYI, 625-line interlaced video at 25fps/50Hz is commonly referred to and recognized as PAL, (even though PAL was developed as an analog broadcast format) whether you accept that or not. The same is true of NTSC and 525-lines, etc.


As for Japan, please read the posts through - the voltage issue was corrected before your helpful and pleasant diatribe.


There is a way of getting your point across without resorting to needless hostility or condescension. I think you'll find that can be a two-way street.

Apologies - I meant neither to condescend nor to be hostile. If you felt that I was - then I do apologise, my posts were not meant in that manner, merely to highlight the correct terminology, so that people who weren't aware of the differences would be, and may cease to repeat them.


I DO get quite annoyed by the incorrect use of the "PAL" nomenclature - particularly by DVD publishers who should know better when describing digital component, not composite, material and using the shorthand of PAL=50, NTSC=60.


This may also be a Europe vs US issue. In Europe we have so many different standards whizzing around (BBC 1" and 2" VT labels had 405, 525, 625 and 819 tick boxes for line standards, as well as PAL, NTSC and SECAM boxes for chroma standard) we've probably had to be a bit more specific with our definitions. Certainly when you are working in a broadcast environment PAL = composite.


What is worse is that people are now referring to "PAL HDTV" and "NTSC HDTV" - which is completely bonkers. I also get a bit annoyed by the "PC-isation" of video - where U and V are used incorrectly when describing digital colour difference signals. You only have to look around at the misunderstandings when it comes to video levels in PC video applications to see how little heed is paid to standards (cf black and white levels) in some cases.


As for my comments about Japanese power - I missed the original post correcting - and did add something to the other correction - as I've seen quite a lot of 10Hz flicker on Japanese 60i video caused by 50Hz mains lighting.


Again apologies - I guess I can be a bit vociferous on the PAL vs 50Hz debate.


Sorry

(And I am pretty chilled out!)