Interlaced DVDs, how to backup them?

[Instant Martian]

Hi guys,

I finally am going to backup a couple of TV series I bought years ago (here there is an old thread I started at the time).
The first series is NTSC 29.970 interlaced video (I can't see any 3:2 pattern, the interlacing artifacts occur randomly whenever there is an object in movement).
I still use a CRT TV so it doesn't bothered me right now, but sooner or later I'll have to switch to a modern flat TV, which (if I understand it correctly) will be progressive.
I was going to start with the first DVD but on my computer screen (also a CRT but progressive) I noticed the interlacing artifacts at once.
So my question is:
which is the best backup strategy to preserve as much quality as possible and don't be bothered by those artifacts in the future on a new display?
I use DVD-Rebuilder and I know there is an option to de-interlace the video. Should I follow that route or what else?

Thank you.

[DB83]

I have had a quick read of that topic. I think you are confusing pull-down - applying 3:2 to film source to achieve NTSC dvd speed - to pure interlacing. DVDs can be interlaced (more common) or progressive and the original source could be film (effectively 24 fps) or video or even a combination. Many early tv series were filmed on 16 mm stock.

Now to give you my opinion on your above question. If you have interlaced footage then you keep it interlaced. No brainer really unless you want to lose 50% of your vertical resolution. You just let your player handle the de-interlacing if you have to.

IMO your current playback issue could be a combination of several things. CRT tvs do not always deal well with NTSC to PAL playback. Your dvds could be a mixed bag due to a combination of source material. So fix one thing - the combing/interlacing - and create a whole bag of new issues.

[Bernix]

Hi

unless you want to lose 50% of your vertical resolution.

even if using Bobed maybe Yadif ?
Only problem with interlaced content is efficiency of x264 interlaced compression (probably solved nowadays). Progressive is better compressed. And if you want deinterlace your DVD check field order. If is it top field first TFF or Bottom field first BFF. Somewhere I read NTSC DV1 is using bottom first, but don't know.
Bernix

[Instant Martian]

Hello and thanks for replying.

IMO your current playback issue could be a combination of several things. CRT tvs do not always deal well with NTSC to PAL playback. Your dvds could be a mixed bag due to a combination of source material. So fix one thing - the combing/interlacing - and create a whole bag of new issues.

I have no playback issue whatsoever right now.
The first time I watched the original DVDs on my CRT TV and they played well (except for the jerky horizontal movement typical of NTSC video). And I didn't notice any interlacing artifact.
Today I was going to start the real backup (on DVD-R) so I moved to my computer and on that screen I noticed clearly the arifacts.
My concern was about avoiding the artifacts on a new (future) TV.

Now to give you my opinion on your above question. If you have interlaced footage then you keep it interlaced. No brainer really unless you want to lose 50% of your vertical resolution. You just let your player handle the de-interlacing if you have to.

So I just leave it alone?
Is de-interlacing a common feature on DVD/BD players?

[DB83]

As you read above, it is a matter of opinion as to whether to de-interlace or not. I just state my opinion. But I guess you would have to de-interlace with avisynth for best results. Beyond my expertise.

Maybe de-interlace at player level is not common. I can only write of my own Sony HDD/DVD recorder which has this feature.

[manono]

So I just leave it alone?

Yes.

Is de-interlacing a common feature on DVD/BD players?

Yes, and of televisions. If your video wasn't deinterlaced when watching on the computer monitor, then perhaps the deinterlacer was turned off. I keep mine turned off so I can study my sources better. Or perhaps the video was encoded as progressive. Most players depend on the flags to tell it's interlaced or not and won't deinterlace unless the flag says it was encoded as interlaced. Save yourself the trouble of reencoding everything.

Why not take one of the DVDs to a friend's house - a friend with a progressive display - and test out one of them?

[Instant Martian]

Hi manono

Yep, I used VLC and deinterlacer was off. I just made another test enabling it and (after trying a couple of different deinterlacing methods) I got a good (not perfect but pretty decent) result.
(I turned it off again now).

Or perhaps the video was encoded as progressive. Most players depend on the flags to tell it's interlaced or not and won't deinterlace unless the flag says it was encoded as interlaced.

Uhm... interlaced video can be encoded as progressive and still remain interlaced?

Why not take one of the DVDs to a friend's house - a friend with a progressive display - and test out one of them?

I'll see what I can do.

OT: the background music on the main menu is pretty loud compared to the audio of the episodes so returning to the menu is annoying. Is there a quick way (i.e. no demuxing) to fix it?
(The answer is 99% "No" but... who knows).

[johnmeyer]

IMHO, you waste your time deinterlacing. When you switch from a CRT to an LCD TV, that LCD will have a perfectly fine deinterlacer that will be used when needed. So, why kill a huge amount of time doing something that you don't need to do?

If you respond, "why not do it?" my answer is simple: because deinterlacing always degrades the video. Yes, this will be true whether you do it yourself, or whether the TV set does it, but since when you do it you will ALSO be re-encoding, your version will have encoding artifacts, whereas when you send the interlaced video directly to the TV, it will not re-encode, so you won't get those additional blocking and other types of artifacts..

Also, once you have deinterlaced and thrown away the original, you can never go back to the original pristine quality. It is gone, gone, gone, never to come back.

Since this question has been asked and answered hundreds of times, the usual response is that you can do a better job of deinterlacing using QTGMC or other advanced deinterlacer. Perhaps. But I doubt you'll ever seen the differences under normal viewing, with typical source material. Don't get me wrong, QTGMC's deinterlacing is absolutely brilliant, and is better than just about anything I've seen. However, compared to what is built into most decent (more than $200) LCD TVs, it isn't light-years ahead.

[DB83]

OT: the background music on the main menu is pretty loud compared to the audio of the episodes so returning to the menu is annoying. Is there a quick way (i.e. no demuxing) to fix it?
(The answer is 99% "No" but... who knows).

Simples. But not for an ancient CRT tv (well not as far as I can recall). When you get a more modern tv you will also get an audio mute button on the remote. Most menus are overkill any way.

[Instant Martian]

Simples. But not for an ancient CRT tv (well not as far as I can recall). When you get a more modern tv you will also get an audio mute button on the remote. Most menus are overkill any way.

Ah ah, funny
I have the mute button on the remote but that doesn't work if you, for instance, fall asleep during one episode and as soon as the player returns to the menu the audio is deafening.

Quite frankly, the longer this CRT will last the better. I was already happy with SD and DVD.

IMHO, you waste your time deinterlacing. When you switch from a CRT to an LCD TV, that LCD will have a perfectly fine deinterlacer that will be used when needed.

Well, I missed that little bit of information.
If it is so I'll simply use DVD-Rebuilder with no deinterlacing.

I think this case is solved.

Thank you.

[manono]

Uhm... interlaced video can be encoded as progressive and still remain interlaced?

Uhm... yes. There's a difference between what the content is and how it's encoded. For example, most progressive movies on PAL DVD are encoded as interlaced. The reverse can also happen (although rarely) where interlaced content is encoded as progressive. By far the most common kinds of DVD players are the so-called 'flag reading' players. Those players will see the progressive flag turned on and automatically not deinterlace it. Only the better (and more expensive) 'cadence' players will check the content, and not just the flags, and deinterlce interlaced material encoded as progressive.

[Instant Martian]

For example, most progressive movies on PAL DVD are encoded as interlaced.

And in this case the flag reading player would deinterlace, wouldn't it?

[manono]

Yep, which makes what is done to movies on PAL DVD pretty bad, no matter how good the deinterlacers are these days. But it's easier for the encoders because they don't have to make sure there's no stray interlacing to worry about.

[Instant Martian]

I didn't grasp the tech stuff completely but thank you.