How can I identify and change my Mpeg2 interlace mode?

[Jimmydeath]

Hello

I am converting some old home movies recorded in analogue Hi8 PAL format, I have used Virtualdub to capture an AVI and then used TMPGenc to convert to Mpeg2 format followed by the Ulead DVD studio to create a DVD.

I am quite pleased with the results however the picture suffers from nausea inducing judder when watching rapid horizontal movement which I believe (from studying the forums) is caused by having the interlacing starting with the even rather than odd lines (or vice versa).

I tried to reconvert using TMPGenc by splitting then re-encoding the files but using the alternate interlace option i.e. A rather than B but the results were still the same.


So here is my problem.

How do I tell what the interlace mode (A or B) of a particular file is, no matter what I do Ulead reports it as A?

Given that I no longer have the original AVI's (insuficient disc space) how do I change the interlace of my MPEGs?

Thanks

[Jimmydeath]

Whilst I am a Noob at this sampling/conversion stuff would I be better off posting this question in the advanced forum?

[Jimmydeath]

Crikey this is hard work.....

What I have worked out myself so far is the following:

If you encode in TMPGenc as 'Top field first(Field A)' then Ulead DVD workshop will report it as Field B and then vice versa for 'Bottom field first(Field B)'

My Hi8 PAL tapes were all encoded as 'Bottom field first(Field B)' in
TMPGenc and looked ghastly and in order to convert it to 'Top field first(Field A)' I had to take the following steps using TMPGenc.

1. Convert Mpeg to AVI
2. Convert Mpeg to MP2
3. Change conversion settings to use Field A first
4. Re-encoded

it takes a loooooong time to do this, however it does cure the problem...

so some different questions now:

a) will I lose quality converting to AVI and then back again
b) I there a one step method of regenerating either an AVI with audio or separate AVI and MP2 files.
c) surely there must be a way of changing the field order in an Mpeg without so many steps.

Thanks