Why I haven't taken the plunge -yet. My take on all this. (1 Viewer)

[Lew Crippen]

And how many 1080P Blu-Ray disks can you currently view?

 

[Levesque]

I am looking at 1080p HD-DVDs in my system since 1 month already.

My scaler (Gennum VXP) is properly putting 1080i back to 1080p w/o any problems, and my projector is showing "1080p" in the input info tab. And since it's a 1080p projector, I'm looking at 1080p for real...

 

[Dave Moritz]

You have only heard one the new formats yourself that was decoded from your basic decoder in your player and sent to your reciever. So in fact you have not heard or compaired them yourself! Especially since the HD-DVD player does not have the capability of decoding DTS-HD.

 

[DaViD Boulet]

Is your scaler/deinterlacer applying 3-2 pulldown reversal for your film-based HD DVD content that's coming out the Toshiba in 1080i60?

If not, it's not "real" 1080P. If so, then it is!

dave

 

[Lew Crippen]

Considering that your claim that HD-DVD is not 1080P because one cannot view 1080P (currently) on HD-DVD, it follows that since one can also not view 1080P on Blu-Ray, it too (at least in the States) is not 1080P

Of course both statements are not accurate, because both HD-DVD and Blu-Ray will deliver 1080P this year.

I just observe that your logic is flawed in your claim that HD-DVD is not 1080P because there is currently no 1080P player.

 

[Cees Alons]

It's still beyond me why some people think they will prefer a 1080p image above a 1080i one. There is no difference in the 1080 image once it's safely on your monitor.

There may be differences in conversion logic when converting 180i to 180p or vice versa (and the results from that conversion, please don't call this a "scaler"), but not in any image that is either properly built from a 1080i source or properly built from a 1080p source.

Why would there be?


Cees

 

[RobertR]

I'd say the chances of that happening are....remote.

 

[Dave Moritz]

My question is if you are viewing 1080p at 1080i resolution. How can you say it is real or true 1080p just by applying 3-2 pulldown? The input to the scaler is still 1080i and is not a true native 1080p picture. I am not trying to say that it the end product is not 1080p resolution and I am not trying to imply that it does not look great. I would like to understand how it is that it makes it a true 1080p picture?

true 1080p: able to accept, process and losslessly output a 1080p source input (i.e., HD-DVD, Blu-Ray, 24p camcorders), as opposed to merely creating a 1080p output by deinterlacing 1080i source or upscaling 720p source.

 

[Dave Moritz]

I would love to know where you are getting your information that HD-DVD will be delivering 1080p players this year. I have been asking retailers in my area when 2nd gen HD-DVD player with 1080p output will be available. I have gotten only one answer from retailers here in Phoenix, they don't know when and they have not recieved any release dates on the next gen HD-DVD players!

At this point in time when compairing standard DTS to Dolby Digital I feel confindent in saying IMHO DTS is better. You must have selective hearing as well or do I have to post something 50 times before it counts? While I support DTS I have posted that I would like to hear the new formats and am willing to give Dolby a chance. So your claim that I am so biased that my sig says I am prejudging. Your claim is rediculous and obsured!

Now if my sig read "DTS-HD Supporter or DTS-HD the surround solution" Then your claim that I am prejudging would have merit and would be accurate! Dont confuse DTS with DTS-HD they are not the same animal. Just as Dolby Digital and Dolby True HD are not the same animal.

Almost forgot, as far as the blind test I dont doubt he got the results he claimed he got. I have come across other so called biased results that Dolby claimed they got as well. This does not change that I feel DTS provieds a better sounding product. If I like what I hear in the new Dolby formats once I have the ability to hear them. Then I will give Dolby credit where credit is due.

 

[DaViD Boulet]

Cees,

The key word there is "safely"...in the case of film-based 1080I that means having applied 3-2 pulldown to deinterlace back to 1080P.

there is a difference. Only when a 1080I picture has been deinterlaced using 3-2 pulldown (when the HD feed is 1080i60 as it is from the 1080i output of most consumer devices)...then and ONLY THEN will the '1080P' image on your screen look like the real-orginal 1080p on the disc.

Using any other method to "fill in the lines" of the 1080i signal won't restore it back to the original.

Just like with 480i going to 480p...only using 3-2 pulldown reveral gets you back the real/original 480p.

This is because with film each frame is split into two fields...but that gets you 48 fields per second (from 24 fps film). In order to format that for 60-Hz TV sets...they repeat every 3rd field twice in a row so the fields will "spread out" to fill the 60-field-per-second cycle of american TV sets.

That's call 3-2 pulldown. That's how all 24 fps material is "scan rate converted" if you will for 60Hz NTSC TV.

Now...ideally to create a progressive scan signal from the interlaced signal...you'd just take the two fields that originally represented a single frame and "zip them back up" again. The problem is that since every 3rd field is repeated twice it would throw off any simple "zipper"...that's what Faroudja was able to fix back in the 1990's with their first-ever 3-2 regognition algorithm so it could strip out the extra fields used to pad the 48 fields out to 60 and then it could just zip back the originals.

That's true for any 24 fps film-based signal that's been "interlaced" for 60Hz...you've got to reverse the 3-2 pulldown first, then zip back the fields into their original frames.

If you do this, you get back the EXACT original progressive-scan signal used before the whole interlacing thing took place.

That's now routine for DVD players and TV sets with 480I filmbased material.

However, because it takes more math, it's very rare for film-basd 1080I to get properly deinterlaced back to 1080P using 3-2 reversal and field-zipping. Most 1080I is just converted to 1080P by "filling in the gaps" between the lines. I still looks good...but not as sharp or detailed as real 3-2 deinterlacing would look.

Hope that helps explain!

 

[DaViD Boulet]

Since film is converted to interlaced by taking whole frames, splitting them in half, and then repeating every 3rd half twice in a row...if you just reverse the steps you get back the exact original progressive signal.

That's what it means to say using 3-2 reversal for deinterlacing film-based material.

This is ONLY TRUE WITH FILM-BASED MATERIAL...that's the only time you can actually "restore" the progressive original without loss. If you start out with a "1080i capture" like sports feed using 1080i cameras...the best you can do is interpolate since each field represents a different point in time.

With film, every two filds (ignoring the extra field you get every 3rd) represent the *same* moment in time...a single frame of film. Put them back together and you've got it.

 

[Cees Alons]

That's what I said, David.

The conversion between the two (and its product) may be flawed. But not the technique (interlaced vs progressive) itself. Some seem to think that.


Cees

 

[Rachael B]

Dave, I've already seen HD-DVD displayed as 1080p on a Sony set at Tweeters.

 

[DaViD Boulet]

Since film is converted to interlaced by taking whole frames, splitting them in half, and then repeating every 3rd half twice in a row...if you just reverse the steps you get back the exact original progressive signal.

That's what it means to say using 3-2 reversal for deinterlacing film-based material.

This is ONLY TRUE WITH FILM-BASED MATERIAL...that's the only time you can actually "restore" the progressive original without loss. If you start out with a "1080i capture" like sports feed using 1080i cameras...the best you can do is interpolate since each field represents a different point in time.

With film, every two filds (ignoring the extra field you get every 3rd) represent the *same* moment in time...a single frame of film. Put them back together and you've got it.

 

[Dave Moritz]

Thanks for the explanation David, very much appreciated

 

[DaViD Boulet]

Cees,

in that case you need to apply 2:2 pulldown to restore a 1080i50 signal to true 1080p.

The main point I'm trying to make for everyone is that "field zipping" the right fields back together into their original frame-pair is the ONLY WAY to properly take a film-based interlaced signal and turn it back into a progressive one.

However, this is exactly what most high-def progressive-scan displays do NOT do!

They just "fill in the lines" and nobody complains.

Time to complain!

Get your real 1080P. Buy a 1080P monitor that touts proper frame-reconstruction for 1080i film-source signal. Don't settle for "fill in the lines" deinterlacing for your film-based 1080i feed.


Why am I making such a big deal out of this? Because Cees you're right that interlaced-transmission is a valid way to send film-based 1080 from one device to another without loss...but this is ONLY TRUE if the receiving device zips the right fields back together to recreate the progressive scan. Since hardly any HD displays do this, it's misleading to cause people to think that "1080i is fine" since it most likely will not be in their own system.

If they have a display that can accept native 1080p and a device that can output it...then you bypass the whole deinterlacing step and that simplifies things. Once it become commonplace to see proper film deinterlacing on HD gear...it won't matter either way.

-dave

 

[Cees Alons]

That's what really puzzles me! Note that standard TV does it right for years and years already.
In fact, I never encountered a (healthy) device that didn't do it right.

Bad one for the HD manufacturers!


Cees

 

[DaViD Boulet]

Hey Cees,

The fields aren't really the same... One field is all the even lines, and one field is all the odd...but each pair of fields in a 50Hz PAL speed-up transfer do represent a complete frame when zipped back together. But it still takes a smart computer chip to try to anaylize them and figure out which ones "match" and zip back together to represent an original frame of picture information and which ones are next to each other but don't relate (ie, a field from one frame and then a field from the following frame). When mistaken fields get zipped you see combing.

Faroudja was really the company that made this all possible with standard-def 480I. They were the first guys who figured out how to program a computer chip to "recognize" 3-2 and 2-2 field-patterns and then figure out which fields are supposed to get zipped back (pairs) and which belong to different fields. It wasn't easy! They even took another scaling company (dwin) to court when Dwin figured out a way to do the 3-2 pulldown reversal thing too. Thank goodness they lost.

Faroudja used to charge $20,000 for a deinterlacer that could do this. That's what you would have paid in 1997 for the priviledge of properly zipping your film fields back into the orignial frames.

Once Faroudja lost the court case with Dwin (trying to say they had a patend on film-recognition and 3-2 reversal!), then they took another strategy to make $$. Instead of charging $20,000.00 for processors for high-end AV nuts, they decided to put that math on cheap chips that they'd sell to DVD player manufactures and display-device manufacturers and make money a different way...through volume.

It worked. And not only did Faroudja stay in business, but we all now can take 3-2 pulldown and film-pattern recognition (for 2:2 as well for PAL users) for granted in cheapo-gear.

All that math was constructed arouns 720 x 480 pixel fields/frames. The math is more complicated when going to 1920 x 1080 fields/frames. Plus, most people thing "interpolated" 1080P looks great and since they haven't seen true 1080P from film-reconstruction approaches they can't compare.

I'm hopefully that within a year Faroudja will put 3-2 for HD on their same chips...and we can start to take that for granted as well!

dave

 

[Levesque]

Gennum VXP, Realta HQV and the new NSC chips are the only one on the market right now able to do proper 3-2 pulldown reversal with 1080i. The Sony Ruby internal video processing (DRC) can also do it.

So it's "real" 1080p when using my Gennum VXP chip. And since I also have a Sony Ruby, I have 2 ways of getting back 1080p from my HD-DVD player...

 

[Nils Luehrmann]

So how many consumers out there have equipment with the Gennum VXP, Realta HQV and the new NSC chips or Sony's Ruby? Not bloody many.

Given that, I can understand the disappointment from those who do not but do have 1920x1080 displays and are so far only being offered players that output 1080i.