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De-interlacing and Scaling Explained


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#101 CoopersPale

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Posted 30 June 2006 - 03:01 PM

Hi Guys,

Nice debate.

Now, I do actually have some n00b questions related to the topic, but not so related to the "aftermath". :blink:
I'd really appreciate some help with this kind of information, as (I hope) would other newbies.



I'd like to start by taking the simple example of a HD set top box, connected to some LCD screen.
Please tell me if I'm thinking about this correctly:
- You can recieve through broadcast, interlaced and progressive digital formats at different resolutions. Can you recieve in Australia, some 50Hz interlaced signal where there is motion between each interlaced frame, i.e. 50i native? Are the broadcast sources in Oz only the ones that are orignally 25p broadcast as 50i?
- What sources are 50i native? Camcorders? VHS?
- What hardware can deinterlace 50i native? Is it assumed hardware that can deinterlace your 25p at 50i will also do the native?


- So, lets say my HD reciever is getting a signal, and I'm watching TV (funny, that). How can I tell if the source is interlaced (or native interlaced!) or progresssive? Are there set top boxes or display options on any screen/HD box that will tell you? Anyone got a link to one?

- Where is the de-interlacing and scaling performed? Is it in the HD set top box, or is it done by the screen? Anyone got an example of a HD box or screen that can perform deinterlacing using something other than bob? I take it some products are better at scaling/deinterlacing than others, is it typical that you can muck around with the settings of your HD box to let the signal through to the screen unmolested, so the screen may do the job? And the reverse, is it typical you can force the screen not to do this stuff, and let the HD box do it?
- Anyone know of any products that are good examples of this?




Now... let's delve into a more complicated situation, the HTPC.
Again, please set me straight if I'm wrong here.

Typically, your DVB-T card will decode the input signal, to get the streamed video, and the player software you are using will read the input buffer, and shove the data into the video card, for output to the screen.
Alternatively, if I'm playing some pre-recorded file, DVD or whatever, we have a similar process, the player is decoding the DVD/xVid/divx/mpeg/whatever, and giving it to the video card.

Now come some questions:
- Can you/should you perform signal deinterlacing scaling at which level? Are the input decoder cards capable? Any card examples?
- Can you do it in software, through the player with something like FFDshow (not that I can find a manual, that would be great, btw, a ffdshow guide...)? FFDshow seems to have multiple deinterlacing options, with freak-assed names I have never heard about... and no doco.
- Can the video card be doing the work? I take it video cards can do better than just bob, thesedays? Anyone got an example of a card that does this?
- Should you just let the screen do it?

- How can you tell if a source is interlaced or not?
- What about detecting interlacing inside xvid files, how do you know if a source is interlaced or not? I take it that the hardware is just smart enough not to attempt to deinterlace or scale something that is already the right size and progressive...

#102 Stephen Dawson

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Posted 01 July 2006 - 09:27 PM

I've seen it quite often on news graphics, weather graphics and other graphics, and also is easily visible on the World Cup footage which is shot at 1080i, where you can see the white lines against the green background.

On problem with a lot of TV overlay graphics (not all, but much of it) is that it is produced in composite video format. The Bug Brother Up late games graphics are a prime example. You can see plenty of dot crawl, which is a dead giveaway, and incipient moire in the tiny horizontally scrolling 'games conditions' lettering.

#103 Stephen Dawson

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Posted 01 July 2006 - 09:54 PM

Often the quality of the deinterlacing in a good quality digital display will be superior to that in cheaper progressive DVD players.

I have learnt a huge amount from this discussion. Thanks Darklord.

I'm presently using a very expensive ($30,000) 3 chip DLP projector and thanks to this discussion I've noticed something I probably wouldn't have previously. Elsewhere you recommend a test DVD, but I'm reluctant to purchase it because it has limited relevance to Australia. I checked it out and it looks interesting, but I've already been through the whole Video Essentials thing of finding that NTSC test patterns aren't of very much use when what we mostly watch is PAL.

Instead I've gradually been capturing program material which seems to illustrate various points, and all have the advantage of being in PAL.

One I've been using a lot lately is a snippet from a Sunday night movie, which being film sourced only requires weave deinterlacing, in which the station the station has run a horizontally scrolling public service message across the bottom of the screen. I've kept this on my Topfield and copied it to a DVD for convenience.

Now this projector uses Faroudja DCDi, which of course is highly reputable. In the projector's setup menu you can choose 'on' or 'auto' for cinema mode. With video-sourced interlaced TV material, fed via S-Video, neither is particularly satisfactory. In 'Auto' mode the interlacing is simply not recognised and weave deinterlacing is implemented. The result is extremely heavy combing, especially on the Aussie Rules footy match showing on TV at the moment. That forces you to select 'Off' for cinema mode. But what does 'Off' do?

That's where my little test snippet proved useful. As it happens, it seems that 'off' forces the projector into bob deinterlacing mode. This wasn't obvious for what I speculate are two reasons. First, the picture itself was not especially sharp in any mode. Second, I think bob deinterlacing somehow tricks the eye into seeing most of the full resolution, turning the sequential delivery into spatial resolution.

BUT, having read this forum entry, I was able to recognise a giveaway of bob deinterlacing: moire pattern. At one point in the clip, a character moves vertically on the screen and his patterned jacket exhibited this moire, although it didn't with the cinema mode set to 'Auto'. Rewinding the Topfield with cinema set to 'Auto' and a similar moire pattern was shown. The reason is that in pause, fast forward, and rewind the Topfield drops one of the fields to avoid combing problems.

So in this implementation at least, the Faroudja DCDi is doing a pretty poor job, failing to detect interlaced PAL (so we're not even talking HD here) and using bob when forced into non-film mode. Maybe Faroudja DCDi can do better in other implementations. I'll be paying very close attention from now on.

#104 pneu

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Posted 02 July 2006 - 12:49 AM

Can you recieve in Australia, some 50Hz interlaced signal where there is motion between each interlaced frame, i.e. 50i native? Are the broadcast sources in Oz only the ones that are orignally 25p broadcast as 50i?


Some examples of native 1080i50 programmes are the Today show, Mornings With Kerry-Anne, 9am with David and Kim, Fresh Cooking With The Australian Women's Weekly, Totally Wild, and The Young And The Restless (probably 60i to 50i conversion though).


- What sources are 50i native? Camcorders? VHS?


HD 50i/60i is exclusive to video cameras as there is no such thing as interlaced film, however 25p is not exclusive to film sources as HD video cameras can also shoot 1080i/25p (examples: The Great Outdoors, Home and Away, All Saints).


- What hardware can deinterlace 50i native? Is it assumed hardware that can deinterlace your 25p at 50i will also do the native?


Yes.


- So, lets say my HD reciever is getting a signal, and I'm watching TV (funny, that). How can I tell if the source is interlaced (or native interlaced!) or progresssive? Are there set top boxes or display options on any screen/HD box that will tell you? Anyone got a link to one?


The HD STB will tell you of the resolution (576p, 1080i etc.) but they won't necessarily be able to detect if 2 fields correspond to the same frame. If you need to tell the difference between native 50i and 25p as 50i, just spot the frame rate difference. 25fps and 50fps are easily discernable.


- Where is the de-interlacing and scaling performed? Is it in the HD set top box, or is it done by the screen?


The HD set top box can scale it to another resolution if you wish, but it's better to pass the signal through natively and let the display scale as they generally do a much better job.


I take it some products are better at scaling/deinterlacing than others, is it typical that you can muck around with the settings of your HD box to let the signal through to the screen unmolested, so the screen may do the job?
- Anyone know of any products that are good examples of this?


Most HD boxes will allow you to force it to pass through the native video signal for that particular channel at all times.


Anyone got an example of a HD box or screen that can perform deinterlacing using something other than bob?


The only screen I'm aware of that doesn't use bob all of the time for 1080i is the Panasonic 60A plasma (if it detects 25p as 50i it will use weave de-interlacing). Apparently the Sony Bravia LCD's are using something other than bob de-interlacing, but nobody seems to know exactly what it uses (from what I can gather, it's something better than bob but not quite as good as "per pixel" deinterlacing).

But there are more displays on the horizon that should use more than just bob (hopefully) :blink:

#105 cwt

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Posted 03 July 2006 - 02:39 AM

[quote name='Stephen Dawson' date='Jul 1 2006, 09:54 PM' post='436221']
I have learnt a huge amount from this discussion. Thanks Darklord.

but I've already been through the whole Video Essentials thing of finding that NTSC test patterns aren't of very much use when what we mostly watch is PAL.

uote]
Stephen ; The pal edition of Video Essentials can be picked up on ebay.Its authored by the cinematographer of empire of the sun so should be good. :blink:

#106 CoopersPale

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Posted 03 July 2006 - 07:22 PM

Some examples of native 1080i50 programmes are the Today show, Mornings With Kerry-Anne, 9am with David and Kim, Fresh Cooking With The Australian Women's Weekly, Totally Wild, and The Young And The Restless (probably 60i to 50i conversion though).
...
HD 50i/60i is exclusive to video cameras as there is no such thing as interlaced film, however 25p is not exclusive to film sources as HD video cameras can also shoot 1080i/25p (examples: The Great Outdoors, Home and Away, All Saints).

So what you are saying is that in Oz, we have people shooting video (50i native) and people shooting film/HD video (25p native, broadcast at 50i) all over the shop.
Your HD tuner must be able to handle them all then.


The HD STB will tell you of the resolution (576p, 1080i etc.) but they won't necessarily be able to detect if 2 fields correspond to the same frame. If you need to tell the difference between native 50i and 25p as 50i, just spot the frame rate difference. 25fps and 50fps are easily discernable.

Easily discernable to the naked eye? No way... how do you tell?

And back to my HTPC example - if you open up some file, does anyone know of some software/setting you can use to show what format the file is in? (I don't mean what codec, I mean what interlacing/framerate/NTSC/PAL is used?)

The HD set top box can scale it to another resolution if you wish, but it's better to pass the signal through natively and let the display scale as they generally do a much better job.
Most HD boxes will allow you to force it to pass through the native video signal for that particular channel at all times.

Again, with the HTPC concept: Do you know a way of passing the video through to the screen for scaling/deinterlacing/etc without the video card doing it? Where can you set that?

The only screen I'm aware of that doesn't use bob all of the time for 1080i is the Panasonic 60A plasma (if it detects 25p as 50i it will use weave de-interlacing). Apparently the Sony Bravia LCD's are using something other than bob de-interlacing, but nobody seems to know exactly what it uses (from what I can gather, it's something better than bob but not quite as good as "per pixel" deinterlacing).

So... uh, how do you actually get weave or better - only through some high end video card?

#107 Stephen Dawson

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Posted 03 July 2006 - 09:49 PM

Stephen ; The pal edition of Video Essentials can be picked up on ebay.Its authored by the cinematographer of empire of the sun so should be good.

If you're talking about Digital Video Essentials, I purchased that soon after it came out. I've also made a number of my own static test patterns which I haven't seen elsewhere. For example, I have one where I have alternating black and white scan lines. When I first started using this, it was quite instructive on how vertical scaling affected detail, but most revealing of all was how a couple of displays simply found themselves unable to lock onto it! One was an Sony projector. That was a while ago, though, and the Sony projectors I've reviewed in the last year or two have had no problems with it.

I also find the patterns on the THX Optimiser included on quite a few commercial DVDs to be very useful. But for motion testing, I am gradually gathering snippets of movies and SDTV material which are revealing of various issues for compilation into a useful test DVD. It'll be a while, but I when I've finished I'll try to remember to make it know and could make it available for those interested.

#108 cwt

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Posted 04 July 2006 - 01:40 AM

If you're talking about Digital Video Essentials, I purchased that soon after it came out.
I also find the patterns on the THX Optimiser included on quite a few commercial DVDs to be very useful. But for motion testing, I am gradually gathering snippets of movies and SDTV material which are revealing of various issues for compilation into a useful test DVD. It'll be a while, but I when I've finished I'll try to remember to make it know and could make it available for those interested.

Left out the word digital Stephen ; my oversight.Digital Video Essentials is available in the original ntsc and now the Pal and also the Hd tv version.It was ages before the Pal version became available.The thx optimiser on Star wars etc is great for getting close to the optimum.Id love to know how the static test patterns you've developed sort out the next generation projectors that have HQV or possibly gennum scalers built in.The new Yamaha comes to mind - If its released out here of course :blink:

#109 pneu

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Posted 04 July 2006 - 08:45 AM

So what you are saying is that in Oz, we have people shooting video (50i native) and people shooting film/HD video (25p native, broadcast at 50i) all over the shop.
Your HD tuner must be able to handle them all then.


Yes, but remember it's purely a 1080i50 transmission, so none of the equipment along the chain needs to know whether or not 2 fields come from the same frame in order to display it correctly.

Easily discernable to the naked eye? No way... how do you tell?


Well...don't you notice how a movie looks different to sport on TV? 50fps is fluid, 25fps has a slight gating in between frames. Panning at 25fps is a dead give-away, it's quite unsmooth.

And back to my HTPC example - if you open up some file, does anyone know of some software/setting you can use to show what format the file is in? (I don't mean what codec, I mean what interlacing/framerate/NTSC/PAL is used?)
Again, with the HTPC concept: Do you know a way of passing the video through to the screen for scaling/deinterlacing/etc without the video card doing it? Where can you set that?


Sorry I don't have any experience with HTPC, better off letting one of the other guys answer your question (or post it in the Digital TV Tuner Cards & Network Media Players sub-forum).

So... uh, how do you actually get weave or better - only through some high end video card?


Yes, or a standalone video scaler.

#110 Stephen Dawson

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Posted 04 July 2006 - 10:05 AM

Left out the word digital Stephen ; my oversight.Digital Video Essentials is available in the original ntsc and now the Pal and also the Hd tv version.It was ages before the Pal version became available.The thx optimiser on Star wars etc is great for getting close to the optimum.Id love to know how the static test patterns you've developed sort out the next generation projectors that have HQV or possibly gennum scalers built in.The new Yamaha comes to mind - If its released out here of course :blink:

Static test patterns are for assessing static image qualities only, of course (although this do impact upon ultimate moving picture quality). That's why I'm gathering clips of moving material for assessment of these aspects of performance.

#111 Darklord

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Posted 04 July 2006 - 01:59 PM

Stephen,

Just a quick reply as I’m about to travel to Japan. I’ll discuss this topic with you in your more detail when I return mid August.

I have learnt a huge amount from this discussion. Thanks Darklord.


No problem. I’ve learnt a few things myself (there is ALWAYS more to know when it comes to video processing!) and have found this discussion very interesting.

I'm presently using a very expensive ($30,000) 3 chip DLP projector and thanks to this discussion I've noticed something I probably wouldn't have previously. Elsewhere you recommend a test DVD, but I'm reluctant to purchase it because it has limited relevance to Australia. I checked it out and it looks interesting, but I've already been through the whole Video Essentials thing of finding that NTSC test patterns aren't of very much use when what we mostly watch is PAL.


The Silicon Optix DVD has no real bearing on PAL/NTSC 50/60hz. It contains flags and patterns for both 2:2 cadence (50hz film sources) AND 3:2 cadence (60hz film sources). In addition it has test patterns for every unusual cadence known to man, and a variety of de-interlacing tests which are relevant to both PAL/NTSC sources. In other words it will test bob/weave/motion adaptive abilities for PAL/NTSC devices with complete accuracy.

Don’t confuse the HQV DVD with PAL/NTSC calibration discs. It can in no way help you optimise a display/video source’s image quality. Rather it simply tests the device to give you an accurate indication as to its de-interlacing/processing abilities. In short it tells you just how bad the processing of the given display is! Its industry standard conformity is what makes it such a valuable tool for A/V reviewers. For the first time ever there is now a proper benchmark by which the video processing of video devices can be accurately judged.

Hmm.. I’m starting to sound like an add for Silicon Optix but I think you get the point.. :blink:

Instead I've gradually been capturing program material which seems to illustrate various points, and all have the advantage of being in PAL.


The term “PAL” has in all honesty now lost relevance to today’s A/V industry. In fact to be complete geeky and “nit picky” with you, unless you’re dealing with composite/S-Video output PAL itself no longer exists. RGB/Component/DVI/HDMI are all different standards to Phase Alternating Line, and the only relationship they can share with PAL is their legacy refresh rate and resolution. If you use component/HDMI output from a DVD Player to a digital display, the video has never been PAL.

Nowadays it’s more accurate to refer to sources as 24p, 50i or 60i (along with their horizontal resolution figure) as these make up the majority of industry standards. If you’ve captured material from DTV or region 4 DVDs then as you know you’re dealing with 576i50 (either native 50i video or 24/25p derived 50i) which is certainly a good way of testing the processing of a given display. However 480i60 2:2 video (as seen on the HQV DVD) will actually test the display’s de-interlacing in the same manor, and given it tells you what to look as part of the test, for you’ll quickly see whether a display “locks on” to a given cadence. If it passes for 2:2 480i, it will also pass for 576i50 2:2 film sources.

One I've been using a lot lately is a snippet from a Sunday night movie, which being film sourced only requires weave deinterlacing, in which the station the station has run a horizontally scrolling public service message across the bottom of the screen. I've kept this on my Topfield and copied it to a DVD for convenience.

Now this projector uses Faroudja DCDi, which of course is highly reputable. In the projector's setup menu you can choose 'on' or 'auto' for cinema mode. With video-sourced interlaced TV material, fed via S-Video, neither is particularly satisfactory. In 'Auto' mode the interlacing is simply not recognised and weave deinterlacing is implemented. The result is extremely heavy combing, especially on the Aussie Rules footy match showing on TV at the moment. That forces you to select 'Off' for cinema mode. But what does 'Off' do?

That's where my little test snippet proved useful. As it happens, it seems that 'off' forces the projector into bob deinterlacing mode. This wasn't obvious for what I speculate are two reasons. First, the picture itself was not especially sharp in any mode. Second, I think bob deinterlacing somehow tricks the eye into seeing most of the full resolution, turning the sequential delivery into spatial resolution.


This is a common problem and is another strong argument against interlaced scan broadcasting in general. As soon as video titles, overlays, graphics or any other kind of material is keyed into digital film sources on television, the cadence is nearly always destroyed. What should be clean 2:2 film material can become 1:1 50hz (50 unique fields a second) and hence the processing either causes combing by staying in weave mode (as you clearly noticed with DCDi) or falls back on bob, losing resolution and introducing artefacts.

This is where next generation per pixel motion adaptive de-interlacing comes into play! Going back to the HQV DVD as a reference one more time, it actually contains a test for this very problem (although from memory its 3:2 film with 60i graphics overlaid) and of course it causes havoc with most processing. Guess which video processing technology passes the test with flying colours maintaining full resolution with no artefacts? HQV processing of course! :D. HQV analyses material on a multi-field per-pixel level, and then applies sophisticated motion adaptive de-interlacing/noise reduction/scaling on a “per pixel” level. It also has the most advanced cadence detection available, allowing it to lock onto the most obscure video cadences comprised of different film/video/graphic combinations. The result is locks onto different type of video sources extremely quickly, then weaves together parts of the fields without inter-field motion and interpolates on a per pixel level parts of the fields with inter-field motion. Finally it cleans up noise (again using a multi-field analysis method) and applies a diagonal jaggy filter to remove unnatural jagged edges from field interpolation (similar to DCDi). Pretty damn cool!

What also sets HQV processing apart from the competition is that it can do all this magic to 1080i sources. As a comparison not only is DCDi limited to 480i/576i SD sources (its completely inactive when you feed your projector an HD source) but it is unable to lock onto anything other than the most basic film/video cadences.

While DCDi was considered state of the art only a couple of years ago, times have moved on, and until Faroudja develop a chipset capable of 1080i per pixel motion adaptive processing/noise reduction and 1024 tap scaling, HQV will remain the king of video processing. Particularly now that they have announced plans for their affordable Realta line of processing chips specifically designed for displays (meaning this kind of processing will soon be available in affordable plasmas/LCDs etc).

You can read about the benefits of HQV and how it all works here.

BUT, having read this forum entry, I was able to recognise a giveaway of bob deinterlacing: moire pattern. At one point in the clip, a character moves vertically on the screen and his patterned jacket exhibited this moire, although it didn't with the cinema mode set to 'Auto'. Rewinding the Topfield with cinema set to 'Auto' and a similar moire pattern was shown. The reason is that in pause, fast forward, and rewind the Topfield drops one of the fields to avoid combing problems.


Exactly. Moiré is a dead giveaway of bob. Have a look at the difference of bob vs weave moiré pattern in these screenshots: bob / weave.

Other noticeable artefacts of bob are shimmer (particularly noticeable in fine detail such as venetian blinds, car grills, crowds and trees) and aliasing along all jagged edges (due to uneven interpolation). Line flicker will also be evident where fine horizontal lines are present.

Static test patterns are for assessing static image qualities only, of course (although this do impact upon ultimate moving picture quality). That's why I'm gathering clips of moving material for assessment of these aspects of performance.


DVE PAL does contain moving Snell & Wilcox patterns for testing de-interlacing under motion. However they don’t tell you much and the multiple tests on the HQV DVD are far more useful.

DVE PAL remains a very valuable calibration tool though.

Anyway, I’m afraid I have to run, but I look forward to discussing this with you in more detail when I return in August.

#112 Luke.VDC

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Posted 04 July 2006 - 09:49 PM

Definately an excellent discussion guys.

I have personally found the HQV Benchmark DVD to be quite useful. I have definately found the noise reduction pattern to be helpful for testing most video processing on how well it removes the noise from the image with good success. Also like Darklord has stated, the cadence tests are excellent for all the types that are out there. A pity it isnt in the PAL format yet but hopefully they bring one out. At the moment just limiting to using 480i output to test the video processing in a DVD player, Plasma or Projector to name a few. Its definately a useful tool.

I also have DVE: Professional edition and there definately is more patterns to muck about with than the consumer version although most wouldnt use them and have no need for them during a basic setup. But the moving zone plate patterns are definately a way to see how well the processor handles. And a couple of extra motion patterns throw in for testing greyscale and such.

#113 ckent

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Posted 05 July 2006 - 10:12 PM

Actually I was watching the game last night (this morning) and noticed for the first time that the pitch lines painted in the grass, which were nearly horizontal, showed some mild aliasing every few lines. This all pointed to a quick-n-nasty scaling down from 1080 to 576, so I'll get back to you.

CK.

#114 pneu

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Posted 06 July 2006 - 01:49 PM

I notice if SBS do their own editing of the matches it sometimes looks really nasty and aliased. Was it live or replayed by SBS?

The pitch lines are interesting to watch, they clearly become aliased as soon as the camera starts panning around (especially up/down) and do a nice job of demonstrating that interlace video really only offers half the vertical resolution under motion. Progressive scan all the way!

#115 ckent

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Posted 07 July 2006 - 12:42 PM

Yeah this was the live version, but I know what you mean -- the re-edited versions go through an analog loop, possibly even composite; you can at least notice the blanking on the left/right has appeared out of nowhere.

Anyway you were talking about the pitch lines producing staircasing while the camera pans, and that's quite easy to spot as a 576i problem. But just to be clear, I was talking about a far more subtle effect, when the camera is dead still: The lines (in some matches only, maybe!) show a very fine staircasing, not every line, but every 5 or so. It's just possible this has everything to do with 1080i->576i conversion, because they may be doubling a few lines to achieve 1152 lines, then halving that to 576.

CK.

#116 matt47x

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Posted 10 September 2007 - 09:46 PM

Hi
So from what i know 10 transmits its HD in 1080i format. So this would mean they are using interlaced cameras and then our sets use an interlacing technique (which one?) to display on a progressive display?
On the other hand, if they use progressive cameras why would they be transmitting in interlaced format?

Cheers
Matt

#117 rosejenifar

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Posted 21 October 2008 - 08:32 PM

Scaling:
If you are scaling your video,you are sometimes presented with an option as to which scaling algorithm the program uses.The differences between most scaling algorithms are subtle,with the exception of Nearest Neighbor,which you should avoid like the plague.The methods are:
*Bicubic- The most common method,found in Adobe Premiere and After Effects.Bicubic is good for scaling for as much as twice the size of the original and down to half the size of the original.Anything more or less and blockiness becomes rather noticeable.
*Sine- Less common that bicubic.Use sine (if available) for when you greatly want to enlarge or reduce your video (more than 2x),for it performs better than bicubic in extreme cases.
*Bilinear- Samples pixels adjancent to the source pixel to determine the output.Old and certainly not the best, but better than nearest neighbor.
*Nearest Neighbor- As stated above,the worst scaling algorithm.It simply duplicates the nearest pixel,yielding a very blocky result.

Deinterlacing:
NTSC's interlaced nature looks fine when displayed on interlaced TVs, yet on progressive scanning computer monitors interlace artifacts can occur (see Interlacing in NTSC Basics for more info).
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#118 kimsmarkin

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Posted 19 August 2010 - 08:03 PM

The following tests were performed with Toshiba BDX2700 Blu-ray Discs, HDMI output, which is directly connected to Westinghouse LVM-37w3 37-inch LCD TVs with 1080p native resolution. BDX2700 Toshiba 1080p set so that test results reflect the performance of BDX2700 video processing.