PAL Interlaced DVD

[ThePanther]

Guys,

I am about to encode "Star Wars Episode 2" to divx.
DVD2AVI says that it is a PAL Interlaced source.

I have never encode a Interlaced PAL DVD before (well
I don't think I did)

Do I have to deinterlace it, and if so, can some point
me in the right direction for some information on how
to go about deinterlacing.

Thanks

[hakko504]

Take a look at the sticky called: DVD2AVI, Force Film, IVTC and Deinterlacing (http://forum.doom9.org/showthread.php?s=&threadid=34718) here in the GKnot forum.
A quick answer to your question is that I'd bet my money that Telecide(post=false) will be your best choise for that movie, if you need any deinterlacing at all.

[N_F]

Originally posted by hakko504
Take a look at the sticky called: DVD2AVI, Force Film, IVTC and Deinterlacing (http://forum.doom9.org/showthread.php?s=&threadid=34718) here in the GKnot forum.
A quick answer to your question is that I'd bet my money that Telecide(post=false) will be your best choise for that movie, if you need any deinterlacing at all.

Could one expect the same or very similar results using VerticalReduceBy2 (fast deinterlace) instead of Telecide() ?

[hakko504]

Originally posted by N_F
Could one expect the same or very similar results using VerticalReduceBy2 (fast deinterlace) instead of Telecide() ? No. VerticalReduceBy2() just averages two lines together, whereas Telecide() tries to match two fields in the best possible way. A frame is built by two fields (top/bottom), and these ahould be matched in this way: 1t1b 2t2b 3t3b 4t4b. Sometimes (PAL) films are screwed up during encoding so they are matched like this:1t2b 2t3b 3t4b 4t5b. Telecide will do it's best to correct this and get the original sequence back. NTSC FILMS on the other hand will always be matched like this:1t1b 1t2b 2t3b 3t3b 4t4b, and the result from Telecide() should be:1t1b 2t2b 3t3b 3t3b 4t4b. As you can see frame 3 has been doubled and needs to be removed. This is accomplished with Decimate(cycle=5).

[N_F]

So when using VerticalReduceBy2 as deinterlacer you could end up with some field errors, where Telecide would do it's best to correct these?

But shouldn't FieldDeinterlace be used instead of Telecide?

[hakko504]

VerticalReduceBy2() will remove one field from the original picture, i.e. 720x576 will become 720x288! Unless you have a fullframe movie that you intend to resize to 512x288 or 384x288,VerticalReduceBy2() shouldn't be used at all as a deinterlacer. The only advantage is speed. Qualitywise every other choise is better.

fielddeinterlace() should only be used with a genuinely interlaced video. In this case, StarWars2, the source is a progressive FILM, and therefor it is better to use telecide().

[N_F]

OK, it's clearer now.

Thanks.