Interlace or non-Interlace?

[NeWcS]

What is the 'rule of thumb' when using Interlace or non-Interlace?Im doing dvd>svcd


TMPG 2.57

Thanx

[snowmoon]

VCD = Non interlace all the time
SVCD = Interlaced when doing interlaced materal.

Film = non interlaced
TV = probably interlaced
Camcorder = most probably interlaced

[NeWcS]

ok, how do I determin when to use it or not? is there something I should look for when framserving?(DVD2avi)

Thanx

[stormcrow]

dvd2avi will tell you as it processes whether the source is int or not, although it is not always accurate i've found. grab ifoedit and just open an ifo, it can tell you whether or not it's int, and more accurately i believe.

[wulf109]

Bitrate Viewer will tell you whether a vob is interlaced or progressive and it will supply a lot more info about the file .

[Poplar]

From an authoritative source, DVD Video(TM) is designed for interlaced display. You may want to ask, what about progressive frames?
This is one answer:

"There's enormous confusion about whether DVD video is progressive or interlaced. Here's the one true answer: Progressive-source video (such as from film) is usually encoded on DVD as interlaced field pairs that can be re-interleaved by a progressive player to recreate the original progressive video. See 3.8 for further explanation of interlaced and progressive scanning." (Jim Taylor's DVD FAQ)

No matter what your source is, it will be displayed interlaced, unless you have a progressive scan DVD player and TV.

I assume most of us don't have both of them, so the question is what should we do? Some will tell you, leave interlaced material interlaced. But this is not applicable to all cases, because you can clearly see some annoying artifacts on TV, which you didn't see on original material. This is because DVDs can get away with it by using high bitrates, usually above 4Mbit/s. We usually encode Mpeg-2 stream with a maximum bitrate of 2.6Mbit/s, which means we can't get away with those artifacts on many ocassions, beause there are just not enough bits to fill in the gap, so to speak.

So the rule is there is no rule, test it for yourself and choose best result. Last advise, if you decide to deintertlace, choose a good filter. A bad filter can blur your picture considerably, which is why some people are against deinterlacing.

[banjazzer]

Most PAL DVDs are progressive (not-interlaced). The exceptions are generally DVDs derived from TV shows. NTSC DVDs are quite likely to be interlaced. You will know when you get an interlaced source in DVD2AVI preview, because the horizontal interlacing effect is usually unmistakeable. I would suggest using your eyes as the final arbiter. If you treat the source as progressive and then fnd horizontal artifacts, you know you were wrong.

[NeWcS]

What if in eoncode using NTSC-Film templete(Asuming the source to where force film is applied)?

Does this apply to NTSC-FILM too???

[banjazzer]

Force film is only going to convert from 29.97 to 23.976fps. If you are encoding an interlaced source to VCD then I believe you should de-interlace it. For SVCD viewed on a TV this should not be a problem, although it won't look good viewed on a PC. However, I deal almost entirely with non-interlaced material, so perhaps someone with more experience of interlaced source material can answer this?