Is DEINTERLACING necessary?

[tomasine17]

Hello everyone. I've captured an avi cartoon file in 720x480 with VD capture using the HuffyUV codec. I used the deinterlace filter in VD. The resulting uncompressed avi appears to still be interlaced. I want to be able to watch this cartoon on a HDTV (i.e. in high resolution) without seeing interlacing lines all throughout the picture. I then use TMPGenc to convert to dvd mpg format (720x480), and my question is, what mode of the deinterlacing filter should I be using in TMPG? I check the enable filter box, and have experiented with the None option, Double, and Even-Odd. Do I have to do this step at all in order to not see lines in the resulting mpg file?

[mrtristan]

You need to enable the filter by checking the box. Once it's enabled, the different settings will yeild different results. Anything that's even will only use the even feilds. Likewise, odd will only use the odd feilds. Double will use both feilds and combine them, something like the default setting with the Virtualdub deinterlace filter. Even-odd feild will use both feilds, but it will also double the frame rate. Be sure to change the frame rate back to 29.97 manually.

Double will give you the smoothest results, but scenes with high motion will have blurry single frame stills. I would stay away from stricly even or odd feild, since that discards half of the information in the frame. Even-odd feild will give you the sharpest results.

Most people who will end up watching a DVD on television don't bother to deinterlace.

[tomasine17]

Well i don't want to create any extra work than is needed. All I really want is to make sure that when it comes time to watch this video on a HDTV, that I don't have horizontal lines in the picture. Right now, when I pump it out to my regular 27" TV, it looks fine. Will it look the same on a hdtv? And when is deinterlacing needed if not in this case?

[vhelp]

@ tomasine17,

high definition is progressive, as I understand it. So, you worry is warranted.

I think that you will have to try each and every method of the deinterlace
filter(s) in tmpg till you've found the one that works for you (or as best as
possible)

Cartoons are nortoious for having weird Interlacing. They tend to dup a
frame or two during it's sequence. Also, the Interlace is usually illregular.
2,2,2,1,2,3, etc, etc.
So, your only choice is to deinterlace as best as possible. However, I've
seen some cartoons that do Telecine too. so, you may want to have a
look at the source you capture, inside vdub and observe each frames
pattern:

* 3p,2i or 3 progressive frames, and 2 interlace frames = IVTC method
* anything else will = deinterlace method

Rase your bitrate as high was your dvd player will allow, and your taste
in quality goes.

Good luck.
-vhelp

[tomasine17]

Well I just recorded some cartoons off of tv this morning, and I just checked out 4 or 5 of them with what you said. Most of them are 4 frames normal, and then 1 interlaced, so its 4:1. Sometimes during the faster motion scenes its 1 progressive, and 1 interlaced, every other one. I only found one small piece of one toon where it was going 3:2. It doesn't seem to stay constant throughout any of the cartoons, but usually its 4:1 throughout and 1:1 when theres fast motion. It's all been recorded in 29.97 fps.

Also even-odd produces a much larger file than double. Double seems more blurry. I've experimented with them all, and I also read that 'double' produces the smoothest results. I also just tried leaving it at None, with the box checked, but I notice it will uncheck itself sometimes and I have to recheck it.

[mrtristan]

If you leave it at none, it won't deinterlace at all. You have to select one of the options.

The best thing to do is to burn a DVD and test it on your HDTV. Although HDTV is progessive, it's probably backwards compatible with an interlaced signal. If not, wouldn't HDTVs have problems when an HD signal isn't being broadcast? I don't have one, so I'm just guessing.

Even-odd produces a larger file, because it automatically doubles the frame rate. You have to go back to the first window and adjust the frame rate back to 29.97. If not, you'll have video at 59.94fps.

[disturbed1]

HDTV is both progressive and interlaced, which is mute, since the final output isn't being HDTV broadcast, unless of course you have a Blue Ray burner, or Xserver.

If it's already interlaced, TMPG's input settings should read interlaced, and encoding mode should read interlaced.

Deinterlacing only add artifacts and slows down the encoding. More time for less quality

[Laddydaddy]

Try frameserving from VD using the deinterlace filter. Try the "blend fields together" mode and see if that helps.

[tomasine17]

So what everyone is saying is that an HDTV will handle the interlaced video without showing the lines because it is a progressive display, and that any deinterlacing on my part would be a waste of time. Problem is that I don't have a HDTV to test it out on, but was planning on purchasing one soon, and didn't wanna find out that everything I have been encoding is gonna look like crap. It looks fine on my 27" tv. Will it just look much clearer and crisper on the HDTV if it looks fine as is now on my regular TV? Can anyone tell me a case in which I would have to use deinterlacing?

Right now I use the VD deinterlace filter with the "blend fields together" mode and the uncompressed avi's still come out interlaced, but I think it is supposed to come out that way because the files are huge and uncompressed. Maybe it is doing a little deinterlacing, but not much.

[Laddydaddy]

Although you are using the deinterlace filter in VD when you capture, I'm suggesting that you frameserve to TMPG from VD and use the VD interlace filter with "blend fileds together" as the mode. Maybe that will help.

[tomasine17]

not sure what this framserve is that you speak of.

[Laddydaddy]

Go to https://www.videohelp.com/virtualdubframeserve.htm and read the guide. It will explain how to frameserve using Virtual Dub. You basically load your avi into virtual dub, and apply any filters you like. Then you start VD in the frame serve mode and it will send the film to TMPG (or whatever encoder you use) frame by frame using the filters you have applied. If you have any questions after you read the guide let us know.

[tomasine17]

The real problem for me is that if I don't deinterlace, then I am not able to watch the cartoon on my 27" tv right now. But as everyone says, when I get an HDTV, it will handle the interlacing, and produce a smooth picture for me so I don't see any horizontal lines. I want this to happen now on my regular TV, so i guess the answer is that I have to deinterlace and sacrifice losing a little quality in order to watch it now pleasureably, since I have not purchased an HDTV yet. Also, if I want to give these cartoons to any friend of mine who most likely will NOT have an HDTV, the video also has to be deinterlaced. I cannot simply leave everything deinterlaced just because I own a HDTV, if I did, because then nothing would look right on the poorer people's sets if I were to burn these files to DVDs and play them through friends players. Am I right or wrong?

[tomasine17]

one more thing...the only question I believe which remains for me now is whether to use Double or Even-Odd (and which mode of even-odd) mode for deinterlacing. I have tried both and they look the same, but even-odd makes a much bigger file size and takes almost twice as long to encode. I am encoding cartoons, so if anyone has an experience as to knowing which filter looks better, please let me know.

I will try the frameserving as you suggested LaddyDaddy. Thanks

[txpharoah]

I'm having a hard time following what all you people are saying. It makes little sense.

If you record anything from tv, it is interlaced. Period. It requires the interlace to retain its quality. Deinterlacing only harms the quality. If you have interlaced video, and it looks bad on your tv, it's only because you have your fields being played back in the wrong order. Most capture cards grab video from TOP A FIELD instead of the broadcast BOTTOM B FIELD standard. When you encoded, you made a mistake.

Don't worry about HDTV if you do not have one. If you have an HDTV, it should playback interlaced video if it is reverse-compatible. The only thing not interlaced is some DVDs and HDTV broadcasts. Everything else on the planet (not on computer) is interlaced. Most computers playback interlaced source just fine with the correct program with a 60hz refresh rate on the monitor. Try PowerDVD or WinDVD to view interlaced source on a PC - it'll look great.

Deinterlacing harms footage. Why can studios make great progressive output you ask? Well, for starters, they go back to the progressive source. They don't capture their own stuff from tv.

So not only is Deinterlacing NOT necessary, it's not even suggested.

And as you've seen, because of all the lines involved in cartoons, it will be MUCH MORE noticeable.

There is also a lot of BAD advice being given out here on the best interlace method. Each method has it's own problem. Read up at 100fps.com for info on interlace theory.

[vhelp]

@ tomasine17,

Don't mind if I ask a domb question, but..

What are you capturing those Cartoons from ??
* VCR
* Cable
* Satellite

Also, if you are not satisfied w/ TMPG's many De-Interlace filters, how
about trying those in vdub, as there are many variations to choose from,
and with lots of configs for most.

Also, if you are ok w/ AVIsynth, there are a few de-interlace filters there
as well, and not to mention other means of de-interlacing (but w/out using
a de-interlacing, but are more for the experienced to trial and error these
variations in AVIsynth) It does sound a little confusing, but it takes time to
find new ways do do something (in AVIsynth) and I don't have the time to
go into great details w/ a beginner - sorry.

But, do try the above out anyways, as you never know what might work if
you have more room to play in.

Good luck thus far.
-vhelp

[tomasine17]

vhelp,

I'm capturing from cable tv, and I use the deinterlace filter in VD in the first place on blend fields together when I capture with vd. Still the video comes out interlaced. I suppose because I am capturing uncompressed?


txpharoah,

I'm a little confused myself, so sorry for the added confusion. I was wrong when i said it was interlaced on my TV. The video appears interlaced on my computer monitor, so I naturally assumed that it would appear as interlaced on the HDTV since that is also a high resolution display. So you are saying since most HDTV's are reverse compatible, that it will display the image fine, and that computer monitors cannot handle it for some reason or another? I use PowerDVD to view the video, and it appears interlaced using that. I still see the horizontal lines appear during movement in the scenes on my computer monitor. I'm assuming this is the way it is supposed to work. The video is interlaced, and it appears that way on the monitor, but the tv doesn't show the interlacing since it is a low res display. So please just reassure me that just because its interlaced on my monitor that it won't be when I purchase a HDTV. Otherwise all this encoding is for nothing when I do eventually switch over.
Thanks for the help.

[bbb]

I don't deinterlace in real time while capturing--is this what you are doing?. I deinterlace after capturing.

You can do this by opening your captured AVI in VirtualDub (VD) and applying one of the blend deinterlace filters. Actually, the blur filter also works similar to the blend deinterlace filter. After blend deinterlacing, it will look somewhat blurry (depending on which deinterlace filter and filter setting) so I apply a light to moderate sharpen filter (and sometimes unsharp mask). This should take out the interlaced lines and without appearing noticeably blurry.

So, for general blend deinterlacing purposes, these are the steps:
1. Capture to AVI.
2. Open AVI in VD and use one of it's Blend Deinterlace filters.
3. Frameserve (or save as a new AVI file) to Tmpgenc.
4. Use Tmpgenc to encode using progressive (non-interlaced) settings.

*Note: With cartoons, you can often inverse telecine (IVTC) them with great results, even from TV captures. This has been proven on these forums. You really have to try IVTC to see if it works well with your particular cartoon (e.g., if panning scenes look smooth then using IVTC should be fine).

Actually, you can do a lot to clean up TV captures using VirtualDub/AVISynth/Tmpgenc filters. It takes some time to get to know when to use a filter but the results can be stunning.

For my personally captures, I almost always use some type of blend deinterlace. I also use many filters to noise reduce and clean up the video. I've encoded and compared deinterlaced video and interlaced video using the same AVI source and I found that you really can't see the difference on an analog TV (but you will see a difference on a computer screen/HDTV--deinterlaced video looks better). Granted, I do use a lot of filters but I truly do think it's worth it since it looks so much better on all types of video screens.

My typical filters for VHS tapes are: VD Smart IQ Smoother-->VD SmartDeinterlace (blend mode)-->VD Sharpen (moderate)-->VD Unsharp Mask (light)-->Tmpgenc NR (light to moderate)-->VD Lanzcos Resize to SVCD Resolution--VD Unsharp Mask (very light). For animated features, I tend to try IVTC to see if it works (many times it does work). This takes about 14 to 24 hours of just filtering for 1 hour of captured video.

Of course, you don't need to use all those filters (just use blend deinterlace and sharpen) and that should shorten your filtering time by a whole lot. And if you don't even want to think about it, you can also encode using Tmpgenc's interlaced mode which will keep your video interlaced (just make sure you are using the right field order or your video will look shimmery/juddery on an analog TV). HDTVs I assume should have some sort of deinterlacing engine for old interlaced material. However, from what I've seen and read, TV deinterlace engines are far from perfect. Only the top of the line hardware deinterlace well (e.g., Faroudja).

So, I prefer to deinterlace on my own. The benefits are worth it for me:
(1) Progressive material is easily resized and converted to different formats without having to worry about interlace lines showing up in the video--such as when converting to Divx, Xvid, Quicktime, VCD, SVCD, DVD, HD DVD. You don't have to worry about using the wrong field order (e.g., a problem for interlaced DV material and some capture cards) which creates shimmery/juddery motion playback on analog TVs if you encode with the wrong field order.
(2) Progressive material looks great--I don't have to rely on imperfect deinterlacing engines of Powerdvd/Windvd or cheap hardware deinterlacing engines. In fact, PowerDVD excessively blends interlaced material and does so with much more blurry results (compared to my own deinterlaced video). Windvd often lets some interlace lines slip in here and there in some scenes which is annoying and detracts from the viewing experience.
(3) Most importantly, Progressive video is less taxing on bitrates which means less macroblocks and mosquitos will appear in your MPEG video (especially video with a lot of rapidly changing/moving elements).

In the end, the choice is up to you. You can throw in the towel and encode in interlaced mode and be at the whim of imperfect software/hardware deinterlacing engines and further perpetuate this out dated video structure. Or. You can start deinterlacing your video which will result in more pleasant viewing on all viewing screens (TVs and HDTVs alike).

In fact, I too started out with Tmpgenc's Double Deinterlace and progressed to using VirtualDub deinterlace filters which give you more control over the process and creates clearer, more pleasant video. I haven't looked back ever since deinterlacing my videos.

[tomasine17]

WOW! bbb, you are the man!!! Thanks for the great response! I am going to try some of the things you said. I usually apply the deinterlace filter in VD on blend fields mode WHILE capturing, but it doesn't seem to do anything. I have left it on anyways.

Do you have any idea why IVTC works on cartoons when they don't follow the 3:2 ratio? I've checked some cartoons, and most of mine are 4:1 on slow scenes, and 1:1 on fast scenes. And also, how can I tell if IVTC did in fact work? What will I see if it doesn't? I've tried it before and from what I remember it was a little fuzzier, or I couldn't tell a difference from regular deinterlacing, so I stayed away. Also, there was a seperate deinterlacing setting within IVTC which was confusing, and I could not figure out how the tmpg IVTC filter worked.

Also what horiz and vert. values do you use for sharpen?

One of my problems is that I capture so many cartoons from TV, that I usually need to encode about 25 toons a week, which means that I cannot devote the 14 to 24 hours per toon that you speak of. At first I was averaging about 50 minutes per toon, and then lately it shot up to 2 hours a toon after I had been applying more filters. Yes I was using Double and Even-odd in tmpg for deinterlacing, so I will try your frameserving method. Thanks for the help.

[DJRumpy]

Maybe I should clear some things up here. I do own a widescreen HDTV. It does support both types of input (progressive and interlaced), as you would expect. There are some gotcha's though. If your DVD Player is progressive scan, then the output will be set to progressive on progressive material (or your material that is true 23.976, with pulldown flags added). If your DVD players source is interlaced, or telecined with no pulldown flags (i.e. you leave it telecined during the conversion), or it's not a progressive player, and you play this on an HDTV, it will output telecined material to your HDTV. The interlace lines should not be visible.

If your source is telecined, then you should definately try Inverse Telecine (IVTC). Regardless of what's being said here, you CAN restore a film back to it's original framerate without a loss in quality. This depends entirely on how your source was telecined, how noisy it is, and whether or not the telecine job is done throughout the entire video. Since your source is using a wonky pulldown pattern, then IVTC can, and probably will guess the pattern wrong from time to time, which may result in the filter dropping a wrong field or two. In a non-animated video, this could be a problem (causing a jerk in the video). For animation, it's not likely to be as noticable. Motion in animation typically won't use such fluid motion as real life, and as a result, a chopped field isn't as noticable. If the adaptive IVTC filter guesses wrong, or simply cant find the correct duplicated frame, it will simply chop out a frame to meet the 23.976 frames per second. This is why it appears to 'work', even when the telecine pattern is wrong, or your source isn't even telecined.

[tomasine17]

Actually I was speaking of outputting from the computer to the HDTV through my AllInWonder card, not from a DVD player.

[DJRumpy]

I wasn't answering your specific post. For your situation, unless your video card has component outputs, it will output an interlaced signal. For your situation, the video card output drives the signal that your HDTV receives.

[tomasine17]

DJRumpy,

So you are saying that in general, especially for animated video, IVTC is going to be a better bet than deinterlacing since I most likely will not notice the slight dropping of fields.

And you are also saying that if I am outputting from a video card to TV that it really doesn't matter whether I deinterlace or not since the output is going to be interlaced coming out of rca (component) outputs. But if I decide to burn this video as dvd-r, then it would make sense to deinterlace first, since i have control over my output when playing from a dvd player?

[tomasine17]

I've also just recently tried frameserving, and I get a few jumps and skips in the resulting mpg video. Actually what happens is i just see an occasional black horizontal line skip up the picture from bottom to top, as if the picture jumped or lagged for a second. I don't know why.

[vhelp]

hi guys.

@ tomasine17..

If you are capuring Cartoons (animation) to finally burn (w/ hopes) that
one day, you'll be getting an HDTV etc., in any event, you should really
be
examining your source .AVI captures for:
* First, dropped frames. (the mother of all evils) ...will throw off IVTC
* after above, examine your .AVI source for a 3,2 pattern.

FOR IVTC..
* Once a 3,2 patter is discovered, and you are sure that it's through-out
...your .AVI source file, you can perform an IVTC

Now, when you perform an IVTC, and you are usng TMPG, you should
always select 23.976 as your frame rate, and 3:2 pulldown
and then finally encode your clip. Make sure you are encoding to MPEG-2.

However, once you've performed the above, and burned to CD and played
through your DVD player, should you discover that you have some jitters
in your playing, you will need to have another look (but more detail) at your
.AVI source for either dropped frames (though, prob too late) and
going beyond those scenes you already check, verify that some of those
scenes where there is LOTS of moiton, don't have illregular IVTC pattern
(actually, it's Telecined pattern, as IVTC is the opposite)

Once you have determined that your source does in fact have ilregular
Telec. patterns mixed in w/ good clean Telecine patterns, in some areas,
you then have a choice, to fine-tune your:
* IVTC process
* use a de-Interlace (bad)
* or, encode w/ 29.970, and raise your bitrate to help over-come the
...artifacts or blocks you will encounter during encodes of Interlace frames.

Good luck thus far.
-vhelp

[DJRumpy]

So you are saying that in general, especially for animated video, IVTC is going to be a better bet than deinterlacing since I most likely will not notice the slight dropping of fields.

Only if your source is telecined. If its a true interlaced source, and your going to be playing it back on a television, then just leave it interlaced. Deinterlacing it will only reduce the quality.

And you are also saying that if I am outputting from a video card to TV that it really doesn't matter whether I deinterlace or not since the output is going to be interlaced coming out of rca (component) outputs. But if I decide to burn this video as dvd-r, then it would make sense to deinterlace first, since i have control over my output when playing from a dvd player?

Be careful not to confuse composite with component outputs. If your output is coming out of Component (not composite) jacks, then it depends on your card. If it supports progressive output, and your tv supports it, then it could output progressive. If your output is going out via Composite, then your output will be interlaced. Again, this would depend entirely on your video cards configuration. If your burning to media, like svcd, or dvd, and your source is telecined, then you should always IVTC if possible. Make sure you use an adaptive filter, which can handle changes in the pulldown pattern. Even better adaptive filters will pay no attention to the pulldown pattern. They will simply scan for to identical files, and remove the closest matches. This type is useful for video that does not have a standard 3:2 pulldown pattern, or for video where that pattern changes to often.

A telecined video source has duplicate fields, used to create 1 additional frame for every 5 frames. It grabs two fields from those 5 frames to produce an extra frame (converts your video from 23.976, to 29.97 fps). These duplicate fields take bitrate to encode. They take up space, and they are completely unecessary when encoding to cdr/dvd media. By removing these duplciate fields, you restore your source to the original 23.976 fps. When they are burned to your media, you use Pulldown to add a flag to the mpeg stream. This flag tells your dvd player which fields to duplicate to create one additional frame for every five frames. In this way, the playback is 29.97 fps, while the source is truely 23.976 fps.

[wthess]

I'm fairly new to video technology myself, but here's what I've learned. Personally, I wouldn't waste the valuable time it takes to de-interlace. I have a 57" HDTV and yes, it auto deinterlaces. I have a satellite receiver plugged into my HDTV via the S-Video port, which isn't digital and my broadcasts look supurb. I have an antenna for local channels connected to the coax in on the TV. Those broadcasts look fine as well. I have a VCR connected via composite to the TV, and we all know VCR's and composites output an interlaced signal. This, too, looks fine on my TV. Finally, I have a DVD player connected with component (not composite), making it a digital signal. It is a progressive scan DVD Player.

Up until now, I hadn't really thought about if the DVD and HDTV were both in Progressive Scan mode. Are all DVD's recorded deinterlaced or is that done in the analog circuitry? Even if you played back the DVD's in Progressive Scan mode onto an HDTV, I would still not waste time deinterlacing. If you did, you would lose quality and when you took your DVD to your friend's house to watch it on his standard TV.... Additionally, Progressive mode can be turned off in the menu settings of a DVD player. Seems to me it would be easier to do that. However, if you are only going to watch it on your PC, then it would be better to go ahead and deinterlace unless there is some kind of realtime deinterlacer out there.

Note, that this is only an educated opinion. I could be wrong about some things here I'm not aware of. I can only tell you that it looks fine on my HDTV, regardless of the signal and/or source. My computer monitor is a different story, though.

My 1/2 cent worth.

[DJRumpy]

DVD's vary. Most NTSC DVD's are telecined. They are true progressive streams, with pulldown flags, to make them appear as 29.97 fps on playback (telecined). This is not true for all NTSC DVD's. Just most of them. There are also true interlaced DVD's as well.

if the DVD and HDTV were both in Progressive Scan mode. Are all DVD's recorded deinterlaced or is that done in the analog circuitry?

Assuming you have a progressive scan DVD player, your using the Component outputs, and the DVD is telecined, then the output to the television would be 23.976 progressive (assuming it's enabled on your dvd player). If the DVD is interlaced, then the output to the television is interlaced (29.97 fps), even if it's through the component ports.

Even if you played back the DVD's in Progressive Scan mode onto an HDTV, I would still not waste time deinterlacing.

Correct. HDTV can handle both interlaced, and progressive signals. If the television does not support progressive, then the output will be garbled. Most newer progressive scan DVD's support an auto-detect feature to prevent this.

[wthess]

DVD's vary. Most NTSC DVD's are telecined. They are true progressive streams, with pulldown flags, to make them appear as 29.97 fps on playback (telecined). This is not true for all NTSC DVD's. Just most of them. There are also true interlaced DVD's as well.

Yep, good ole' lack of standards! Reminds me of the old CD recorder days, or even better yet, VHS vs Beta vs the other unknowns at the time. The Laserdisc never really did gain much ground, though it was a good format.

[tomasine17]

For frameserving with VD to tmpg, does anyone know if you can create a batch file of videos to frameserve without having to do one at a time?