an Interlace problem I think

[dfgh11]

I've realised recently that I must not understand the concept of interlace.I was brought to this realisation recently when I was backing up a DVD of a TV show, the results of which were all flickery (on TV not monitor) during high levels of movement on screen.Now, usually I back up movies and don't have to deinterlace or use any filters, to get exactly what I want.With this however, I had to.The only way I could get rid of the flickering was to deinterlace when encoding.So does this mean DVD's of TV shows have a different type of interlace, to the interlace on DVD's of movies? If not, why was I getting the flickering? it's worth mentioning that it's an ntsc source

[tito13kfm]

you probably had the wrong field order selected when you converted to MPEG2... by deinterlacing it, it doesn't matter the field order you choose, because it is just merging the fields together.

[johns0]

Actually deinterlacing is removing a field or blending them,not recommended as the picture loses some resolution when removing a field and blending causes artifacts to be seen from previous frames merged.

[dfgh11]

I didn't choose a field order I just used CCE via AVIsynth-maybe this is wrong because I am trying to learn avisynth:
LoadPlugin("C:\dll\mpeg2dec3dg.dll")
mpeg2source("VIDEO FILE HERE")
BicubicResize(720,480)
ConvertToYUY2()

now, I've used this script on movies successfully, which were also interlaced and never had any problems

[SLK001]

Actually deinterlacing is removing a field or blending them,not recommended as the picture loses some resolution when removing a field and blending causes artifacts to be seen from previous frames merged.

Bullshit. Pay no attention to the man behind the curtain.

@dfgh11 - Tell us what your source was.

[dfgh11]

My source was an NTSC DVD of a TV show. I have done many movies NTSC and PAL with a simple script like that, and they all turn out ok. I was just hoping to understand why this has happened this time(with a DVD which contains a tv show), so I can anticipate it in the future, without wasting time and discs etc.

--
It maybe also worth mentioning that I am PAL. But my Tv and DVD players play NTSC or PAL 60, but have never had any troubles in the past. The only time this happened to me before, was when I was experimenting making a DVD of some TV episodes I captured from TV; Which I also did not deinterlace as I thought(just like I thought with the DVD), that everything was already in order, all I needed to do was re-encode.And that time I was using Tmpgenc, and just set all the settings as I normally would when encoding a PAL DVD movie

[SLK001]

My source was an NTSC DVD of a TV show.

Well, what show? Was it recorded live (shot on videotape), or was it based on a film? Why do you guys insist on withholding important information from us?

[dfgh11]

No, it was a pre-recorded show. Just a sitcom. I'm sure the exact name of the show doesn't matter, so withhold it if that's ok. My reasons are my own.

[johns0]

SLK001,you actually believe its good to deinterlace mpgs that are going to be seen on regular tv?With your post count i thought you would know better.

[SLK001]

SLK001,you actually believe its good to deinterlace mpgs that are going to be seen on regular tv?With your post count i thought you would know better.

Well, it depends on what you mean, and it also depends on the source (that's why I asked). Live programs captured on videotape at 29.97fps are indeed interlaced, and cannot be deinterlaced with good results. That's because every field contains unique information.

Now, if you're confusing "deinterlacing" with "inverse telecining", then yes you can perform an IVTC (or convert the 29.97fps telecined video back to its original 24fps film base) and this should actually be done.

If dfgh11 doesn't want to tell us that he's converting his porn collection, then that's okay by me!

[johns0]

Ok,i meant tv programs that are interlaced normally.

[dfgh11]

a Porn sitcom?...sounds like a good pitch.

DVD2avi says it's 29.976 interlaced recorded on whatever TV production companies use to shoot the standard sitcom or television series.

And basically why is that that it won't play smoothly on tv without inverse telecine or deinterlace, if that's what the video was set up for in the first place when the original dvd was made. For all I am doing is downsampling the source, like I have done many times with movies that were interlaced.I'm not messin with the field order, not as far as I know

when I do deinterlace, the picture isn't as good. Edges of objects are jagged etc and when played on a tv it's not as smooth.

[Calitas]

Hi dfgh11

I had that problem to, converting in TMPGEnc AVI to MPEG and getting jerky movie.

In the first attempt to resolve this problem I applied the filter "Deinterlace" --> "Even field" and solved the problem, but I lost quality in video.

The problem whit me, was wrong field order that was "Bottom field first (field B)", instead "Top field first (field A)", changing this setting result whit me.

This setting is in the "Advanced" --> "Video source type" --> "Field order:"

See this page: http://dvd-hq.info/Compression.html

This is an extract from ther:
"Bottom (for DV) or Top (for analog)

This setting is the source of many problems, since some systems don't say what field order they use, and some pseudo-DV systems actually capture in analog mode. The field order is set by the capture hardware, not by the editing program, so you can't change it in software without re-compressing all the footage. All you can do is make sure you set this parameter right, so that TMPGEnc knows how to encode the file. If you notice your MPEG video flickers whenever there is fast movement, the most likely cause is a wrong field order setting. Note that this will only be noticeable on a video monitor or TV set; computer monitors are not interlaced, and always show odd and even lines at the same time."

In this text it's said that in a monitor computer it's not noticeable, for me it's noticeable if I see the video in the Windows Media Player, but if I see in the PowerDVD isn't.

Cumps
Calitas

[dfgh11]

I've tried both fields and I get the same thing with both.
What is making me question any knowledge I thought I had on this subject is this: The video contained within the DVD itself was made to be shown on TV, and all I am doing is duplicating that same video from that DVD, at a lower bitrate. Therefore, shouldn't my resulting video file retain all the original properties of the original apart from the bitrate. And if not, why not?

Like I said I used this script:
LoadPlugin("C:\dll\mpeg2dec3dg.dll")
mpeg2source("VIDEO FILE HERE")
BicubicResize(720,480)
ConvertToYUY2()

now I am just learning how to script, after using tmpgenc all my life, so attribute any "dumbness" in this area to that fact.