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SD DVD Players and Discs A place to discuss DVD players and discs including SD movie DVDs with the emphasis on upscaling to 720p/1080i. Please do not discuss Blu-Ray or HD DVD technology here.

Is it really better?

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Old 02-09-2005, 07:50 PM   #1  
How can anyone watch standard def?
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Default Is it really better?

Hello,

I am considering getting a new DVD player with upconvertor capability. Just wondering, is it really better? I can't help relating it to my experience with digitial photos, and when I try to enlarge them, they start to look pixelated. They say you can't add pixels where there aren't any....I am assuming that the broadcasters have upcoverters that cost thousands when they show a DVD. My guess is the upconvertor in the $250 DVD player must be a mass-produced chip, so I would really like to hear from someone who bought one of these and hear what their impressions are..thanks.
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Old 02-09-2005, 09:33 PM   #2  
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Thumbs up Crash course on "HD DVD"

DVDs today are recorded at 480i. ALL DVDs. Even the extra-expensive ones sold under various marketing names such as "Superbit". DVDs that say they are recorded in high definition mean that better quality equipment was used in digitizing the original film content. But the actual data that gets put on the DVD is 480i nonetheless. In fact it is "compressed" 480i like the digital cable or satellite signals.
Too much compression (because the marketing guys want to save space for putting "extras" on the DVD) damages the image. The "Superbit" DVDs and their ilk use less compression -- putting a movie on 2 DVDs instead of 1 for instance -- and thus yield a less damaged image.
Additional care is taken in the digitizing process as well. But the data on the DVD is still only 480i. DVDs are also designed for 4:3 shaped images. Various tricks are used to put wide screen (16:9) or "wider than wide screen" cinematic movie content on the DVDs. The most important of these is "anamorphic" enhancement which deliberately distorts the wide image so that it fits in the squarer shape without wasting pixels on the top and bottom as unused black bars. DVD players automatically sense and remove this built-in distortion and produce the original wide screen image with better fidelity because there was no such wasted resolution.

So here comes the 480i signal from your source -- complete with color data coming in at only half that resolution or less. Your DLP now wants to scale it up to 720 (really 768p). First the signal goes through the de-interlacer and comes out as 480p. Then the scaler extrapolates the extra resolution it needs -- inventing the intermediate pixels by kind of averaging the real pixels around them. And then the pixels light up. If you paused that image it would not look all that great -- certainly not as good as a photograph. But here comes the next 480i frame and the next and your eye does the final bit of processing by smoothing it all together so that you see an attractive moving image.


The next bit comes when DVD player manufacturers figured out they could sell players for more money if they put a de-interlacing circuit in the players. They could then send a 480p signal to the TV.
They could do this because their cronies (another division of the same company) producing the TVs set them up to take a 480p signal as input, thus by-passing the internal de-interlacing circuit. The logic behind all this was that the DVDs that were being recorded also include special information as to how to do a better job of de-interlacing which the player could see as part of it's processing to produce an analog TV image from the digital data recorded on the DVD. Thus, and this is the important bit, THE DVD PLAYER COULD DO A BETTER JOB OF DE-INTERLACING!

So now you had "progressive" DVD players that would take 480i DVDs -- the only kind that exist -- and produce 480p analog TV signals. The TVs still had their own de-interlacers to handle regular TV signals (which they needed to de-interlace to make their "line doublers" work).

So people would now pay for TWO de-interlacing circuits, plus the extra profit built into bleeding edge technology. And bleeding-edge it was. The idea was fine but the execution was often dreadful. The net result was that the de-interlacing in the DVD players was often WORSE than what the TVs could do on their own. For a variety of technical reasons, de-interlacing the wide range of DVD content out there is a tough job, and on top of that the engineering was often shoddy.
So folks would spend the money for a progressive scan DVD player and then turn off the progressive option and use it like a 480i DVD player because that produced a better picture. The picture was "better" because some data was effectively being filtered out -- discarded -- and thus the TV's de-interlacer produced less noticeable glitches. In fact, many DVD players were having trouble just decoding the digital data on the DVD properly.
If you'd like to see the sorts of problems that can occur, check out the remarkably detailed information in the DVD benchmarks section of the Secrets of Home Theater web site.

Nevertheless the progressive scan DVD players had one big advantage -- they sold like hotcakes. Most buyers assumed they MUST be better and thus any problems they were seeing must be due to faulty DVD content and not the players.

They sold so well that everybody else wanted to get in on the act. So now you had cable and satellite boxes and even tape players putting out 480p progressive signals, which was kind of silly unless the de-interlacer in your TV was particularly brain-dead -- in which case your TV probably had a whole bunch of other problems as well. The "better" picture that most people saw with such boxes was almost always just a result of them switching from "channel 3/4" or "composite" video cabling to "S-video" or "component" cabling, both of which include a higher bandwidth signal -- most notably an improved color signal.

Then came "high definition" TV.

From the standpoint of broadcast TV this was a big thing -- the real deal. This was content RECORDED in higher resolution, digital from inception, and in a wide screen aspect ratio. The industry settled on 720p and 1080i as the new broadcast standard resolutions -- not quite up to the eye-candy of the 1080p they were using for studio masters, but still looking much much better than conventional TV and at a cost the market could be made to bear.

TVs were manufactured that could handle these new signals -- originally expecting the signals to be converted to analog signals over component cables and then including true digital inputs (HDMI or DVI) and internal HDTV tuners. Of course since there was limited HDTV content out there, such sets were often used primarily to watch old, boring standard TV. So to help sell the sets, the marketing people thought up the bright idea of saying the sets would convert standard TV to high definition.
This was basically a new way of marketing the old line-doubling scalers (nothing really new here) plus some real advantage arising since the display element and electronics were engineered for higher bandwidth signals in case they were ever fed a real HDTV signal -- that is the TVs were built more to studio monitor standards.

As the "HDTV" buzzword grew, DVD content producers wanted to cash in. Of course their DVDs were still only 480i, but never let the facts get in the way of good marketing campaign. They discovered that 1080p professional digitizing equipment was being used to digitize the film content -- which was then down-scaled to 480i to be put on the DVD. And that was all they needed to know to call their new crop of DVDs "high definition" DVDs. This while they were compressing the heck out of them (damaging the image) to save space to put CD-ROM games on the same DVD. [I'm being a bit cynical here. Major studios have come a long way towards improving the transfer quality on their DVDs and are only occasionally tempted to let the movie be damaged because they know folks are more likely to buy "special" versions that include extras.]

he next big deal is the "up-scaling" or "up-converting" (a misused marketing term) DVD players. The idea is to get people to buy new DVD players for their new HDTV-ready TVs by doing the same trick they did with the progressive players. I.e., let's put the scaler in the player!

Now remember the TV still needs its own scaler for standard def TV. And fixed pixel displays need a scaler for HDTV as well because HDTV comes in different broadcast resolutions which need to be converted to the "native" resolution of the display.

But heck, if you are going to buy an HDTV-ready TV and "high definition" DVD discs, then you certainly don't want to screw up the vibe by playing them on an old "progressive" player. You want a high-tech, high definition, "up-scaling" player! Just in case you've lost track here, the content on the DVDs is *STILL* only 480i in all this.

The drooling from the hardware guys was so great that it took them a while to hear the screams from the content guys. The folks who make their money selling DVD discs don't want high-res content coming out of the players because folks will just make copies of movies and not buy their discs! The HDTV broadcast networks face the same dilemma but they are already resigned to a business model that makes money by selling commercial time and subscriptions. The DVD guys need to schlep discs.

So the boys in building "A" got together with the boys in building "B" and came up with a solution. We'll allow up-scaling DVD players but only if the high res output is limited to digital connections that we can control with a copy protection scheme. The bosses in building "C" got big grins.

Well it turns out there was a digital cabling standard already in place called DVI. It was used to connect computers to monitors and since HDTV-ready TVs now were built to the high bandwidth and sync-rates needed by computers, many already had DVI inputs so that folks could use them as computer monitors as well.

All that was needed was to clamp a copy protection boot on that DVI input. This rejoices in the name of "HDCP".

An HDCP-compliant source device will refuse to make a digital connection to a display or intervening device which is not also HDCP-compliant. Analog connections will work regardless -- but only at conventional, lower resolutions.

So voila you now had TVs with digital inputs and DVD players with fancy new, up-scaling, high-definition digital outputs. Of course there were some older TVs out there with DVI that was NOT HDCP compliant, but the industry had an answer to that. Buy a new TV. Or use your fancy new up-scaling DVD player just as if it were a previous generation progressive player by connecting it via analog cables at 480p resolution. Since it said "up-scaling" on the box the image must be better, right?

DVI had other problems as well due to it's computer-based heritage. It didn't carry audio for example. So new HDMI cabling was invented to deal with that and to remove some other confusions inherent in DVI. HDMI is, more or less, DVI plus digital audio plus HDCP and with connection standards and protocols more or less attuned to the home theater market.

the big news was that these players could put out glorious 720p or 1080i signals from a DVD disc via those HDMI or DVI connections! "Glorious" here being a marketing term of art. The important thing to remember, the thing I have to keep stressing because I see that buying frenzy gleam coming into your eye again, is that THE CONTENT ON THE DVDs IS ONLY 480i AND NO SCHEME CAN INVENT DATA THAT ISN'T THERE IN THE FIRST PLACE!

The 480i data decoded from the DVD first gets de-interlaced to 480p. Then it gets scaled up either to 720p or to 1080p. If the desired output signal is 720p then you are done. If the desired output signal is 1080i then the signal gets RE-interlaced to 1080i. The TV receives a digital 720p or 1080i signal from the player and SCALES IT AGAIN to match the native resolution of the display.

all but some, of these new generation "up-scaling" DVD players produce a significantly better image than the previous generation of "progressive scan" players. Why this is so is due to several factors.

First the scaler in the player may be better than the scaler in the TV. The closer the player can get the data to the native resolution of the TV the less work the TV's scaler has to do.

Second, engineering continues to advance. Other factors than scaling are likely to be better in a good "up-scaling" player than in the previous generation players.

But the most important reasons why folks get good results from some of these new players is that the data stays entirely in the digital domain.

A player connected by analog cabling, such as S-video or component cabling, has to convert the digital data present on the DVD into analog TV signals. It usually does this as the very last thing it does -- in the video output stage -- because it is so useful to keep the signal in digital form for any other processing it needs to do first. The TV set receiving that analog signal ALSO wants to do processing of various forms -- which are done more cheaply, and for the most part better, with a digital signal. So the FIRST thing the TV does is convert the analog signal BACK to digital form.


up-scaling player sends a digital signal to the TV which just leaves it in digital form. Thus no conversion noise and no filtering.

Given all that, it would seem natural that the best arrangement would be to use a digital connection for a *480* signal, and just leave it to the TV to do whatever scaling is needed -- once. Curiously, that is not often the best way to hook things up. HDTV-ready TV's are optimized for 1080i broadcast signals because that's how they are often judged in stores. That, plus any advantage that comes from having a better scaler in the player suggests that having the player upscale the DVD data and then feed that to the TV will give a better result even though a second scaling pass may be needed. There are additional advantages if you watch movies filmed in older 4:3 shape in that the player can put pillar boxes around the movie content without loss of movie resolution because the player is sending a higher resolution signal.

But just as with the progressive players, there are some up-scaling players out there which are nothing but hype. Engineered by the school of shoddy, they are just not worth the money. And there are undoubtedly folks who will buy up-scaling players and find they end up preferring the signal they get hooking the thing up via S-video at 480 resolution, simply because their TV does a better job doing what they paid to have the DVD player do.

That's because there are two competing technologies lining up to fight the battle to become the new -- TA DAH! -- high resolution DVD format. HD-DVD and Blue Ray differ from current DVD technology in that the data on the disc is actually encoded in high resolution. Such discs won't be compatible with current DVD players. You'll need to buy a new DVD player that truly deserves the moniker "high definition" -- applause from the boys in building "C".

Such a player will output a 720p or 1080i signal -- possibly even a 1080p signal -- but that signal will reflect much more what's actually on the disc and much less the art of the scaler engineer.

But again, this is for the future. Up-scaling players for conventional DVD discs are the hot item right now. They are at price points from a hundred bucks to a few thousand.you can get a fine player for a few hundred if you do your homework. You can also get some real crap,
So DO please do your homework.

copied from Mr.Pariseau
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Old 02-10-2005, 12:16 AM   #3  
How can anyone watch standard def?
 

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NO, just wait untill dvd's are better quality and the format war is over
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Old 02-10-2005, 01:54 AM   #4  
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Quote:
Originally Posted by jojojojo57
DVDs today are recorded at 480i. ALL DVDs. Even the extra-expensive ones sold under various marketing names such as "Superbit". DVDs that say they are recorded in high definition mean that better quality equipment was used in digitizing the original film content. But the actual data that gets put on the DVD is 480i nonetheless...
NOT TRUE! All movie-title DVDs are in fact 480p! Place those discs in a PC's DVD drive and use a video analyzer software and it will always report the source video as 480 progressive. Whether the resulting image is 480i or 480p depends on the type of display and the type of connection used. If you are using a standard DVD player with component, s-video or composite connection, then you will get a D/A conversion that results in 480i video. If you use a progressive scan DVD player with a progressive component-video connection, you still get the D/A conversion but the deinterlacing hardware in the player will produce a 480p image. If you use a upconverting DVD player with a digital display like a DLP or LCD TV that has a DVI or HDMI connection, the 480p source is sent straight to the display without any D/A conversion. Then the upconverting player can be set to leave the signal at 480p or scale it up to 720p or 1080i.
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Old 02-10-2005, 02:15 AM   #5  
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As to the OP's question...upconverting DVD players do have advantages over progressive-scan and standard players when you are using large-screen digital displays (DLPs/LCDs and similar fixed-pixel displays.) that have DVI and/or HDMI connections. For example, if you have an HDTV with a fixed pixel display of 1280x720, an upconverting DVD player has a scaler chip that can take the 480p source signal from a DVD and convert it to 720p, allowing the image to be displayed natively on your screen. Keep in mind that all scaler chips use complex algorithms to "fill-in" the missing data needed to convert a 480p image to a 720p image. It will never be as good as a true HD source that was mastered in 720p or better 1080p. But nevertheless, it looks a hell of a lot better than displaying a 480p image on a 720p HDTV where the TV then usually "zooms" the image to fill the physical screen. I own an LCD front projector and with my Bravo D1 DVD player, you can definitely see the benefit of upconverting a 480p image to 1080i on a 102" screen! The misunderstanding takes place when someone buys one of these upconverting players for their 34"/36" or smaller HDTV. It's just too small of a screen to appreciate the scale-up, which is why many of those folks posting on this forum say they can't see a difference between component-video and DVI/HDMI when using an upconverting player.
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Old 02-10-2005, 06:30 AM   #6  
How can anyone watch standard def?
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Default Sounds like it's worth it

Thanks everyone for your input. I guess I need to figure out how to explain to my wife every 2 years that our DVD player is obsolete and that we need a new one.

To be very honest, I just bought a 42" Panasonic Plasma, HD7UY and I have Dish HD. I am in love with HD content on it. I am in a "suburbin fringe" area and cost of antenna plus install is around $300. For that I would get Fox, ABC, PBS maybe NBC too (I hear they have a really weak signal from NYC). Ya know, I just don't really give a s**** to watch any of that stuff and put up with constant commercials anymore.

I think I would rather take my $300 and get an upconverter DVD player than an OTA antenna. (of course I'll have to buy an HDMI input card for the plasma set as well, but that one is destiny anyway)..
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Old 02-10-2005, 11:21 AM   #7  
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Impressive post. Thanks for taking the time.
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Old 02-10-2005, 07:05 PM   #8  
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Thanks Eric ,the hardest part was cutting it up to make it fit with the space restrictions here,and still make sence.50% dident make it . jojo
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Old 02-11-2005, 01:01 PM   #9  
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Quote:
Originally Posted by borromini
NOT TRUE! All movie-title DVDs are in fact 480p! Place those discs in a PC's DVD drive and use a video analyzer software and it will always report the source video as 480 progressive. Whether the resulting image is 480i or 480p depends on the type of display and the type of connection used. If you are using a standard DVD player with component, s-video or composite connection, then you will get a D/A conversion that results in 480i video. If you use a progressive scan DVD player with a progressive component-video connection, you still get the D/A conversion but the deinterlacing hardware in the player will produce a 480p image. If you use a upconverting DVD player with a digital display like a DLP or LCD TV that has a DVI or HDMI connection, the 480p source is sent straight to the display without any D/A conversion. Then the upconverting player can be set to leave the signal at 480p or scale it up to 720p or 1080i.
If ALL dvd`s are progressive why is everyone wanting a fajourdia DE interlacer,Why would you even need a DE interlacer if all dvd`s are progressive,I`m missing something.
I know some NEW dvd`s are comming out progressive and WMP 9 and 10 are at the forefront.I know your into the PC home Theatre is that what your speaking of?
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Old 02-11-2005, 03:30 PM   #10  
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Because all DVD players have a DAC chip that takes whatever is on the disc and converts it from a digital to an analog interlaced signal so that analog connections like s-video and composite can pass that signal along to any display. On progressive-scan players, they add the deinterlace chip between the DAC and the component-video output so that it can be passed on to an ED or HD display as progressive. I wasn't referring to PCs. PC home theaters have a DVD-ROM drive that has a slightly different arrangement with the video card's DAC with the VGA connection being similar to a component-video in that it too supports a progressive signal. Most DVDs produced between 1997 and 2002 were 480i. However with the arrival of digital HDMI/DVI ports on DVD players around 2003, most DVD authoring companies that are contracted with studios now produce those titles in 480p so that you don't end up with an unecessary deinterlace process when using the DVI/HDMI connection.
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Old 02-11-2005, 04:53 PM   #11  
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Thanks borromini, so whats a good reference dvd that in 480p, I believe i`ve read D VE is 480i.
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Old 02-11-2005, 06:12 PM   #12  
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Good question...I'm assuming by using DVE as an example you're referring to calibration tools. I'm anxious for the HD format war to be settled so that one can buy a calibration tool specifically for HD displays.
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Old 02-11-2005, 07:20 PM   #13  
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I knew I had run across this subject before. In this excerpt from http://www.dvddemystified.com/dvdfaq.html#1.1 the situation is the DVD is recorded as interlaced video, but when 24fps film conversions are recorded, they are recorded as two interlaced field pairs at 48 hz from the same film frame. When the DVD player puts the two fields back together, the original frame is reconstructed same as if it were recorded as a progressive frame at 24fps.

The entire article is well worth reading.

Quote:
[1.40] What's a progressive DVD player?
Quote:

A progressive-scan DVD player converts the interlaced (480i) video from DVD into progressive (480p) format for connection to a progressive-scan display (31.5 kHz or higher). Progressive players work with all standard DVD titles, but look best with film source. The result is a significant increase in perceived vertical resolution for a more detailed and film-like picture. Since computers use progressive-scan monitors, DVD PCs are by definition progressive-scan players, although quality varies quite a bit (see 4.1 and 2.12).

There's enormous confusion about whether DVD video is progressive or interlaced. Here's the one true answer: Progressive-source video (such as from film) is usually encoded on DVD as interlaced field pairs that can be reinterleaved by a progressive player to recreate the original progressive video. See 3.8 for further explanation of interlaced and progressive scanning.

You must use a progressive-scan display in order to get the full benefit of a progressive-scan player. However, all progressive players also include interlaced outputs, so you can use one with a standard TV until you upgrade to a progressive TV. (You may have to use a switch on the back of the player to set it to interlaced output.)

Toshiba developed the first progressive-scan player (SD5109, $800) in mid 1998, but didn't release it until fall of 1999 because of copy protection concerns. Panasonic also released a progressive-scan player (DVD-H1000, $3000) in fall of 1999. Many manufacturers have released progressive models since then at progressively cheaper prices (pun intended). It's also possible to buy an external line multiplier to convert the output of a standard DVD player to progressive scanning.

Converting interlaced DVD video to progressive video involves much more than putting film frames back together. There are essentially three ways to convert from interlaced to progressive:
1- reinterleaving (also called weave). If the original video is from a progressive source, such as film, the two fields can be recombined into a single frame.
2- Line doubling (also called bob). If the original video is from an interlaced source, simply combining two fields will cause motion artifacts (the effect is reminiscent of a zipper), so each line of a single field is repeated twice to form a frame. Better line doublers use interpolation to produce new lines that are a combination of the lines above and below. The term line doubler is vague, since cheap line doublers only bob, while expensive line doublers (those that contain digital signal processors) can also weave.
3- Field-adaptive deinterlacing, which examines individual pixels across three or more fields and selectively weaves or bobs regions of the picture as appropriate. Chips to do this used to cost $10,000 and up, but the feature is now appearing in consumer DVD players.
4- And there's also a fourth way, called motion-adaptive deinterlacing, which examines MPEG-2 motion vectors or does massive image processing to identify moving objects in order to selectively weave or bob regions of the picture as appropriate. Most systems that do this well cost $50,000 and up (aside from the cool but defunct Chromatic Mpact2 chip).

There are three common kinds of deinterlacing systems:
1- Integrated. This is usually best, where the deinterlacer is integrated with the MPEG-2 decoder so that it can read MPEG-2 flags and analyze the encoded video to determine when to bob and when to weave. Most DVD computers use this method.
2- Internal. The digital video from the MPEG-2 decoder is passed to a separate deinterlacing chip. The disadvantage is that MPEG-2 flags and motion vectors may no longer available to help the deinterlacer determine the original format and cadence. (Some internal chips receive the repeat_first_field and top_field_first flags passed from the decoder, but not the progressive_scan flag.)
3- External. Analog video from the DVD player is passed to a separate deinterlacer (line multiplier) or to a display with a built-in deinterlacer. In this case, the video quality is slightly degraded from being converted to analog, back to digital, and often back again to analog. However, for high-end projection systems, a separate line multiplier (which scales the video and interpolates to a variety of scanning rates) may achieve the best results.

Most progressive DVD players use an internal deinterlacing chip, usually from Genesis/Faroudja. Some use MPEG decoders with integrated deinterlacing. Some, such as Toshiba's "Super Digital Progressive" players and Panasonic's progressive-scan player add 4:4:4 chroma oversampling, which provides a slight quality boost from DVD's native 4:2:0 format. Add-on internal deinterlacers such as the Cinematrix and MSB Progressive Plus are available to convert existing players to progressive-scan output. Faroudja, Silicon Image (DVDO), and Videon (Omega) line multipliers are examples of external deinterlacers.

A progressive DVD player has to determine whether the video should be line-doubled (bobbed) or reinterleaved (weaved). When reinterleaving film-source video, the player also has to deal with the difference between film frame rate (24 Hz) and TV frame rate (30 Hz). Since the 2-3 pulldown trick can't be used to spread film frames across video fields, there are worse motion artifacts than with interleaved video. However, the increase in resolvable detail more than makes up for it. Advanced progressive players such as the Princeton PVD-5000 and DVD computers can get around the problem by displaying at multiples of 24 Hz such as 72 Hz, 96 Hz, and so on.

A progressive player also has to deal with problems such as video that doesn't have clean cadence (as when it's edited after being converted to interlaced video, when bad fields are removed during encoding, when the video is speed-shifted to match the audio track, and so on). Another problem is that many DVDs are encoded with incorrect MPEG-2 flags, so the reinterleaver has to recognize and deal with pathological cases. In some instances it's practically impossible to determine if a sequence is 30-frame interlaced video or 30-frame progressive video. For example, the documentary on Apollo 13 is interlaced video encoded as if it were progressive. Other examples of improper encoding are Titanic, Austin Powers, Fargo, More Tales of the City, the Galaxy Quest theatrical trailer, and The Big Lebowski making-of featurette.

One problem is that many TVs with progressive input don't allow the aspect ratio to be changed -- they assume all progressive-scan input is anamorphic. When a non-anamorphic (4:3) picture is sent to these TVs they distort it by stretching it out! Before you buy a DTV, make sure that it allows aspect ratio adjustment on progressive input. Or get a player with an aspect ratio control option that "windowboxes" 4:3 video into a 16:9 rectangle by squeezing it horizontally and adding black bars on the side. Because of the added scaling step this degrades picture quality, but at least it gets around the problem.

Just as early DVD computers did a poor job of progressive-scan display of DVDs, the first generations of progressive consumer players are also a bit disappointing. But as techniques improve, and as DVD producers become more aware of the steps they must take to ensure good progressive display, and as more progressive displays appear in homes, the experience will undoubtedly improve, bringing home theaters closer to real theaters.

For more on progressive video and DVD, see part 5 and player ratings in the excellent DVD Benchmark series at Secrets of Home Theater and High Fidelity.

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Old 02-11-2005, 11:17 PM   #14  
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Thanks Rbinck,

So all the info is there on the dvd (480p)its just divided into two halves,hence all progressive dvd players need a deinterlacer to put the two halves back together again in the 480p format.

So in the future we will see true 480p dvd or will that come in the form of HD DVD?

"But sources which are truly progressive in nature are hard to come by right now. Movies on DVD are decoded by the player as interlaced fields. All of the film's original frames are there, but they are just divided into "halves". What we're going to talk about next is how we take the interlaced content of DVD and recreate the full film frames so we can display them progressively. The term commonly used to restore the progressive image is deinterlacing, though we think it is more correct to call it re-interleaving, which is a subset of deinterlacing."
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Old 02-12-2005, 09:24 AM   #15  
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Location: Katy, Texas
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But as the author says, it is better thought of as re-interleaving, because the two halves originated from the same frame of film, thus eliminating the "moton blur" distorton of true interlaced video.


So if you take a frame and divide it into the two halves for recording the even lines first then the odd lines, when you play back those and re-interleave you reform the original frame.

If the main basis for the progressive player being better is the elimination of "moton blur," the progressive player reconstructs progressive video when film is the source and therefore can be legitimately thought of as progressive video.

If the source is from an interlaced video source, TV tape from the Tonite show, etc. then the video will still have any "motion blur" that would occur shown interlaced even though it is output in a progressive format.
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