Remove Interlacing Artefacts without convert to Progressive with Avisynth

[VideoFanatic]

Short Clip Sample. The interlacing looks really bad near the end of the hold. The clip is from a VHS to DVD conversion I demuxed to an MPEG2. It's 720 x 480.

As far as I know the only way to remove interlacing artefacts is to convert to progressive. Is that correct? And when you do so you lose detail and you get slowdown so I don't want to do that.

So I just want to remove the interlacing artefacts but keep the video as interlaced and I don't want to lower the resolution of the video or lower the quality of the video. The video is for viewing on a TV.

Is there any way to do that?

[sanlyn]

As far as I know the only way to remove interlacing artefacts is to convert to progressive.

That's not the only way, but it's often necessary and is probably the best and easiest way to do it.

And when you do so you lose detail and you get slowdown so I don't want to do that.

If done correctly, none of that happens. BTW, the bitrate used for your MPG is too low for action scenes like these.

Interlace artifacts are the least of your problems here. The only way to clean the flutter, streaks, chroma shift and bleeding, levels, and other problems is to work in progressive mode or use SeparateFields(). But SeparateFields() alone won't smooth the interlacing very well. Most people would use QTGMC and re-interlace back to the original configuration.

#[ load the original AVI ]

# ---- Go to YV12 if not there already ----
ConvertToYV12(interlaced=true)

# ---- QTGMC defaul setting works OK most ----
# ---- of the time. Can tweak if needed.  ----
AssumeTFF().QTGMC()     

#[ run some additional cleanup while in progressive mode ]

# ---- reinterlace -------
SeparateFields().SelectEvery(4,0,3).Weave()

[VideoFanatic]

OK is this code correct? Should I degrain while in progressive? Also I can still see some interlacing, how could I remove more or all of it?

Mpeg2Source("H:\New\z = Encode\Original few secs.d2v", CPU=6)
ConvertToYV12(interlaced=true)

AssumeTFF() # or AssumeBFF() depending on the source

# deinterlace
Load_Stdcall_plugin("C:\Program Files\AviSynth 2.5\plugins\yadif.dll")
QTGMC(Preset="Ultra Fast") 

DeGrainMedian(limitY=2, limitUV=3, mode=1, interlaced=true)

SeparateFields()
SelectEvery(4,0,3)
Weave()

[jagabo]

As far as I know the only way to remove interlacing artefacts is to convert to progressive. Is that correct?

That's like asking if there's any way to cut your arm off without cutting your arm off. The video is either interlaced (with comb artifacts) or it's progressive (without comb artifacts).

And when you do so you lose detail and you get slowdown so I don't want to do that.

You can make it 30 fps progressive or 60 fps progressive. The former will be a little jerky/flickery because it has only half the temporal resolution. The latter has all the temporal resolution but isn't DVD compatible.

[VideoFanatic]

I'm making a Bluray disc. So if I make it 60 fps will that get rid of all the interlacing artefacts or do I also need to use QTGMC? Will the quality still be good or do I lose quality making it progressive?

[jagabo]

I'm making a Bluray disc. So if I make it 60 fps will that get rid of all the interlacing artefacts or do I also need to use QTGMC? Will the quality still be good or do I lose quality making it progressive?

You can either leave it interlaced and let the TV deinterlace while you watch it, or you can deinterlace it before encoding. Which looks better depends on how good your TVs deinterlacer is, how good you deinterlace, and how well you encode it. The reason it's often recommended to leave interlaced video interlaced is that if you deinterlace it you will be stuck with whatever artifacts your deinterlacing produces. Your deinterlaced video will never get any better. If you leave it interlaced, the video quality will improve with the deinterlacing abilities of future TVs. But it will be a long time before any TV can deinterlace better than QTGMC.

I don't think 60 fps 720x480 is Blu-ray compatible. Though some players may play it.

I would use QTGMC() to make it 60p (or 30p, ie, followed by SelectEven() or SelectOdd()). If that's too slow Yadif(mode=1, order=1) might look ok, though it will have problems with thin horizontal lines like the ropes. Even a Simple Bob() will work.

[sanlyn]

OK is this code correct? Should I degrain while in progressive? Also I can still see some interlacing, how could I remove more or all of it?

Mpeg2Source("H:\New\z = Encode\Original few secs.d2v", CPU=6)
ConvertToYV12(interlaced=true)

AssumeTFF() # or AssumeBFF() depending on the source

# deinterlace
Load_Stdcall_plugin("C:\Program Files\AviSynth 2.5\plugins\yadif.dll")
QTGMC(Preset="Ultra Fast") 

DeGrainMedian(limitY=2, limitUV=3, mode=1, interlaced=false)

SeparateFields()
SelectEvery(4,0,3)
Weave()

Some notes here:

Interlaced video played on a PC will always look interlaced, but not on TV. If you want to play interlaced mpg on a PC, try VLC Player (you have to manually tell VLC to deinterlace. Pain in the neck). Or try PowerDVD, which uses a variation of bob() to play interlaced mpg. Or use VirtualDub's bob filter for viewing only, though it will look a little soft.

DeGrainMedian will do little to clean up this video and will soften it. At the point it is used in your script the video is progressive, not interlaced. I marked that statement in red.

QTGMC in ultra fast mode isn't likely to perform the repairs needed. Used at default, "QTGMC()" uses the default "slow" preset which will clean much better and retain more detail -- in fact, the default is likely to help replace some of the detail lost in the original odd fields of the clip. Yes, the default is slow. You pay a penalty here for speed.

For a video that needs this much fixing, I'd run QTGMC at slow in one step and save the file as re-interlaced YV12. In a next step, use SeparateFields() to run other plugins for more cleanup work. You can also run everything in a single script, but it will be even slower because of memory swapping for the plugins used.

Also, your script uses the re-processed mpg clip you submitted above (which I believe you stated was a "transfer", which means problems from the original source have already been made worse by DVD compression). You should be working with the original source video.

You can clean up many more problems and get a sharper image using MCTemporalDenoise at "low" or "medium" instead of using a degrainer. Grain isn't the problem (although MCTD does some degraining by default). The other problems are bad chroma bleed, poor saturation, gamma and black levels too high, oversaturated dark blue, chroma shift, chroma noise, aliasing, uneven side borders, and head switching noise at the bottom of the frame.

[intracube]

Interlaced video played on a PC will always look interlaced, but not on TV. If you want to play interlaced mpg on a PC, try VLC Player (you have to manually tell VLC to deinterlace. Pain in the neck).

VLC should automatically deinterlace interlaced video - if it isn't, check the preferences.

If it's still not working, maybe your video isn't flagged as interlaced (mediainfo?).

[sanlyn]

Interlaced video played on a PC will always look interlaced, but not on TV. If you want to play interlaced mpg on a PC, try VLC Player (you have to manually tell VLC to deinterlace. Pain in the neck).

VLC should automatically deinterlace interlaced video - if it isn't, check the preferences.

If it's still not working, maybe your video isn't flagged as interlaced (mediainfo?).

I think it depends on the VLC version. I'm using an older one. <sigh> Keeping 5 computers updated 100% is such a pain. Will try the newest one on the PC I'm on now.

Holygamer, I should edit my remark about blue oversaturation. It looks that way in some shots, not so much in others. That's not uncommon with analog source, especially tape. Maybe working with levels will help.

[themaster1]

@holygamer
I've tweaked your video today. I've watched old 90's wwf on YT to see how they looked like i think i'm not far off. How is the guy called with the hannibal lecter mask ?

script
http://www.mediafire.com/?wpz43y1nud71cfi

[sanlyn]

themaster1, in the image posted above: why are the two posts on the right a different color in the tweak? Luma is OK, but all 3 colors on the bright deck are clipped at the bright end and will "bloom" on tv.

I don't think it's even possible to tweak the earlier Original few secs.mpg. Dirty tape + poor interlace + lots of noise + low-bitrate re-encode = a mess. The low bitrate compression artifacts are one thing (you'll notice they always look worse on fast motion), but most of the problems should have been cleaned up on the source, not later. Most of the worst noise is in the darks, so denoising makes the low end look rather thin. I darkened them a bit, but even though they're too bright in the original they still have low density and look odd. 90 minutes of filtering for this short puppy cleaned things up a bit and got colors out of the bright blown-out range, but those sawtooth edges would look better if they'd been cleaned up at the source before re-encoding.

Fixing the darks is also a problem because the levels change in every shot. Look at the close-in shot a few seconds into the video. IF you make the first shot too bright, the other shots look strange. In any case, working with a re-encode is a nightmare. I don't care the way many of the scenes look, but here goes nothin":



holygamer, any chance that themaster1 or the rest of us could get a short piece of the unprocessed source?

[themaster1]

I guess every one is entitled to his opinion for me the spotlights should be yellow , the ground white/light(very light) cyan and the skin have some pink as they're all caucasians.

In any case this is what i propose now:

I have used mvtools+sharpened + neat + added some grain. I recognize i have sharpened UV with neat to about 150/250% in the mid-lows (lol) probably way too much. Sony vegas vscope seem to appreciate the refinements and my eyes aswell so i'm offcially done with it.

http://www.mediafire.com/?3x860p1x9mczldv


comparison:
original (mpg)/ sanlyn (mpg)/ themaster1 (mpg)

[sanlyn]

Looks OK to me, tm1, but skin seems a bit red. Then again, some of the skin in mine is headed toward yellow (the stress of wrestling? No. Just crappy source, I think). Too bad we couldn't get a sample of the unprocessed source.