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Unofficial VirtualDub Support Forums > VirtualDub Filters and Filter Development > Deinterlacing Fully Interlaced Video Like Tv

Posted by: confused Nov 21 2003, 03:01 PM

I use virtualvub to deinterlace music videos. The one funny thing about videos is if the video is originally NTSC and converted to PAL, all frames will have interlace lines and the only way to deinterlace it, is to apply filters unlike if the video is originally PAL, you can just select the non-interlaced frames. MY problem is, I want to deinterlace those fully interlaced videos AS GOOD AS what I see it in tv. But I've never able to find any good/nice filter for virtualdub. Even the KernelDeinterlace filters for Avisynth doen't work good as it will spoil the motion badly. I'm hoping to deinterlace the video smoothly and also without ghosty problems. Anyone here...please help me. Thanks in advance.

Posted by: Syncroniza Nov 22 2003, 09:03 PM

hmm... I could post now only a link to a deinterlacing guide...But you have luck: I will try to explain some things here to help with your "confusion".

QUOTE (confused @ Nov 21 2003, 04:01 PM)

MY problem is, I want to deinterlace those fully interlaced videos AS GOOD AS what I see it in tv.

You can't deinterlace AS GOOD AS your TV...because your TV doesn't deinterlace at all!

TV sets (normally) display everything just as it is - in an interlaced way. There comes field after field. The computer monitor can't do that - there comes frame after frame.
(look at http://www.100fps.com/ for a good explanation)

So, if you want to watch your video with the computer, you have to deinterlace it. "Smart Deinterlace" for VirtualDub or "KernelDeint" for AviSynth are excellent examples and you should achieve good results with them.
But 'some' information is always lost. If you think that motion gets jerky with deinterlacing, then you could try a bob filter - like Donald Graft's "DGBob".
http://neuron2.net/dgbob/dgbob.html
Thereby your 25fps (for PAL) field-based video gets transformed to a 50fps frame-based video.

QUOTE

The one funny thing about videos is if the video is originally NTSC and converted to PAL, all frames will have interlace lines and the only way to deinterlace it, is to apply filters unlike if the video is originally PAL, you can just select the non-interlaced frames.

I don't know what you exactly meant with this passage... I can only say that interlacing exists in NTSC AND PAL - the format makes no difference there. Perhaps you had a video with a NTSC->PAL-conversion that was performed the crappy, the wrong way. There you have field blends

and you will never achieve 100% perfect results with that input material. (Garbage in - garbage out)

side-note:
Personally, I record a lot of musicvideos, too. It's not the easiest task to process this kind of material - since there is very often all kind of stuff mixed together. In one (PAL-) music video you could find true progressive material, interlaced passages, progressive frames with interlaced effects on top of it (hybrid), hard telecined material... with changes in stakkato style.

Posted by: confused Nov 23 2003, 10:09 AM

what i mean is...let say...a video which is made in USA, it will be in NTSC format. They will telecine the video, which also have some interlaced frames... But you can inverse telecine it. IF the NTSC video convert to PAL format...the frames will be in a mess causing all frames to be interlaced...so you can't inverse telecine like NATIVE PAL videos.

Posted by: confused Nov 23 2003, 10:28 AM

... that filter didn't work good at all

Posted by: Syncroniza Nov 23 2003, 09:17 PM

QUOTE (confused @ Nov 23 2003, 11:09 AM)

Like I said: garbage in - garbage out...
If the input material is messed up in such a way, you can't expect wonders. Some information of the original progressive video is probably lost, so you can't use a simple inverse telecine operation. In most cases you have to deinterlace such videos, yep...

another good tutorial dealing with this:
http://www.doom9.org/ivtc-tut.htm#PALTheGoodTheBadAndTheUgly
(but perhaps you know this document already...)

Posted by: confused Nov 24 2003, 04:59 AM

so sad....yeah i read that guide...their guide didn't do well either....anyway..thanks for helping out

Posted by: gtz Nov 24 2003, 01:09 PM

QUOTE (Syncroniza @ Nov 22 2003, 03:03 PM)

But 'some' information is always lost. If you think that

i really don't get why there should be any information loss in deinterlacing. you just have to extract each field into a frame, vertically stretch by 2 and you have a 50/60 fps movie with no deinterlacing loss at all.

Posted by: Syncroniza Nov 24 2003, 06:22 PM

@gtz:
You describe bobbing! (I mentioned that in my upper post, too...see "DGBob"...)
I referred to normal deinterlacing (so that you get 25/30fps) with your quoted passage.

Posted by: PinkyAndThaBrain Nov 30 2003, 04:28 PM

The problem with bobbing is that it doesnt look all that good ... you are actually adding faulty information, the TV simply leaves the unused fields blank. Your visual system is much better at filling up the gaps than a simple spatial interpolator. For a variety of reasons this wont work well on your monitor though, even if you set the refresh rate to 50/60 or 100/120 Hz. 100 Hz TVs do deinterlace for instance. They use motion compensated deinterlacing and motion compensated framerate upconversion in fact ... unfortunately there are really no equally advanced algorithms available in open source, the only free motion compensated deinterlacer Im aware of (TomsMoComp doesnt count) is this closed source one

http://www.alparysoft.com/prod/deinterlace.php

Posted by: i4004 Nov 30 2003, 07:35 PM

if you have troubles with blended fields(NTSC->PAL gets a lot of these..) and want to toy with a possibility to make 25fps anyhow...(i cannot recommend doubleframerate as it's works poorly on my tv-out..) see this one;
http://neuron2.net/ipw-web/bulletin/bb/viewtopic.php?t=283

you'll have to do avs,as vdub is no master of fields(at all...)
in the future,i'm always goin' to try scharfis stuff prior to encoding to laced mpeg2 (ie. i'll do laced mpeg2 if his stuff fails...) if stuff has blends..(as in this case,i wouldn't do mpeg2 as his stuff saved the 25p day)

i did a bit of testing and i was OK with the results (not perfect,but pretty acceptable,especially after one sees how does this sttuff like with normal telecide or so....in meantime he did some more work on the script....i didn't tried this...)..my source was film but horribly blended,as you'll see in the last sample he posted (that's my stuff...)

he just told me that it won't work on the music-videos,as these have pattern changes on almost every scenechange...(as fcc said here
http://virtualdub.everwicked.com/index.php?act=ST&f=5&t=662&hl=blend&st=30 )

so for music-videos it'll be laced mpeg2 encoding...
(heh,isn't that the reason why fcc is a mpeg2 fan....

)

/ivo

Posted by: BrOwen Dec 26 2004, 07:23 PM

Hi everybody;

I ve been looking for Best deinterlace filter to use in VirtualDub. I capture something from TV and if it is larger than 384x288, the result is interlaced. but VirtualDub deinterlace filter is too bad. "Blend" option makes the result video too much blury which is not good, ya know.

the best deinterlace filter I ve ever used is old flaskmpeg's deinterlace filter. in Flaskmpeg v0.6 there is a deinterlace filter where you can disable "blending" and result is amazing. but i cannot open avi files using flaskmpeg. so i have to use VirtualDub. Please anyone knows a great deinterlace filter, please tell me.

best regards

BrOwen

Posted by: christianng Jan 1 2005, 02:14 PM

The "DScaler Deinterlace Filter for VirtualDub" allows high quality deinterlacing of captured video using VirtualDub.
It utilizes the MoComp2 deinterlacer of the DScaler project. Before deinterlacing the temporal noise filter of DScaler is applied:

http://members.chello.at/christian.neugebauer/DScalerFilter.htm

Posted by: snoclowNIX Jan 24 2005, 06:33 AM

I downloaded this and placed the dll's in the VirtualDub folder and the vdf file in the plugins subfolder. I'm not using AVISynth, dunno if this is a requirement.

I then set VIDEO > FULL PROCESSING and then go into FILTERS. Select the DScaler filter, it shows in my list, but the Configure button remains greyed out. I was expecting to do some configuring, but is there none to be done, it just works?

I captured from a VHS tape using, VirtualVCR, YVU9, NTSC. YUY2 didn't work with my computer.

Please let me know if I'm missing something here.

Posted by: christianng Jan 24 2005, 06:27 PM

A configuration is not foreseen as it is not necessary.
The filter works just fine using the default values.

AVISynth is not required for using the "DScaler Deinterlace Filter for VirtualDub".

best regards, Christian

Posted by: snoclowNIX Jan 26 2005, 10:38 AM

DScaler crashes VDub when I go to run the batch jobs with Xvid but it did look good before while I was setting up filters. The crash is some out of memory range call error.

I tried several different deinterlacers for my pulldown movie clip. The one I'm going with is Deinterlace - Smooth per the www.100fps.com. Passing it through AVISynth (my first use of this program). I'm sticking with Xvid for now.

It does leave the SciFi logo stair stepped, so I'll try a logo remover finally.