interlacing without re-encoding

[mp3boy]

I am re-authoring a DVD and for god knows reason the original m2v file is Progressive, should I Convert it to interlaced? and how do I do that without re-encoding?

thanks

[lordsmurf]

No.

[mp3boy]

no means I cannot do that or I shouldn't do that? what I mean since usual DVD player do not interlace pictures, isn't suppose to be interlaced in source? and if yes how do I do that myself? is it even possible, such thing?

thanks for your quick reply

[borax]

no means I cannot do that or I shouldn't do that?

No means both: You should not do it and (without reencoding) you cannot do it.
DVD standard allows both: Interlaced and progressive. Most commercial DVD's are progressive, only some (pure TV productions) are interlaced.

[mp3boy]

maybe i am missing something but until now 99% of region1 dvd that I checked were interlaced when I tried them by dvd2avi or virtualdub

any way to check that? is there any Official instruction on this interlacing matter?

[Cornucopia]

Here's the Official instruction on interlacing:
lordsmurf said "NO"

But seriously,
Think of your sources:
Films--(should be) Progressive
Most Network TV shows--(shot on film) Progressive
Network TV ads--(mixed) Progressive or Interlaced
TV News & most sports--Interlaced
Local TV & Home Video--Interlaced
Animation--(usually) Progressive

(Assuming NTSC)
It can be progressive @30fps (actually 29.97 on DVD) or at 24fps (actually 23.976 on DVD) as coded. This will be played back on either standard DVD players at 29.97 interlaced or on progressive DVD players as either 29.97 interlaced, or 29.97 progressive, or 23.976 progressive (if you have the right monitor hookup. This may also be frame doubled- or tripled to 48fps or 72fps)

STRONG ENDING:
Since MPEG2 can work either way, the best thing to do is match your source with your final type of display and hopefully not mix them too much. But if you already have an encoded MPEG2 (that is DVD-compliant), DON'T MESS WITH IT or you'll be losing quality.

Scott

[vhelp]

Note, I don't go by what dvd2avi says, when I press the F5 key to
let it play as it outputs the video data specs in that window.

I check the long way, cause it's the sure way (last time I did)

To check this ..

* Open dvd2avi

* import your VOB file (did rip, for instance)

* set it to: Video\Field Operation\None

* jump somewheres' in the mid section of the time-line (for instance)

* highlight just a small section with the "[" and "]"

* then, File\Save Project\filename_of_movie.d2v

Now run "VFAPIConv.exe" and import your *.d2v source file (so you can
make a psuedo AVI file)

Run and open this psuedo AVI file inside vdub. If all the frames that
you go to are all progressive, there's your answer. Other'wise,
chances are, you'll find it Teleciend (PPP II PPP II PPP II)
That's Progress Progress Progress Interlace Interlace

Last time I cheked, the movie "The Fifth Element" was progressive.
It just has flags or something embeded in the VOB files to tell your
DVD player to Telecine (3:2 patter) the source for TV.
(If I get time tonight, I'll check this dvd.. its near by)

.. Also,

Even thought (for instance, this move above) is Progressive, it don't mean
that it will play as such. Beause it won't. It will Interlace every 4th and 5th
frames when you play it.

Another quick way you can check, is play in Powerdvd, if your source is
crystal smooth (no interlace) then you can be sure that the source is true
Progressive film. However, be warned, that if PDVD is set in Auto, then
you will have to change it to (o) Weave (to be sure)

-vhelp

[mp3boy]

thank you very much for your reply, answer accepted

[lordsmurf]

Leave it alone. It is within spec.