Going DVD -> x264 - Do I NEED to de-interlace?

[odditory]

I'm not really quite sure, does one normally de-interlace while doing a DVD->H.264 transcode? I've compared results between the default of not de-interlacing, against de-interlaced videos, and I can't really tell the diff (i guess because my player is deinterlacing upon playback?).

Is there some scenario where de-interlacing is preferred/recommended?

Is any information or quality lost during the process of de-interlacing, that would otherwise remain if one didn't have the encoder de-interlace?

Also, is there a generally accepted answer to whether to "Keep Top Field, Keep Bottom Field, or Reverse Fields" as far as what field order to pick? I've just been assuming Keep Top Field.

thanks guys

-Odditory

[Ranguvar]

Can't answer some of your questions while being confident about them, but to the first, try with and without deinterlacing. If you can't tell a difference, or can barely, then who cares, right? :)

[odditory]

Hah - there's a nice non-answer. Yes you are right though, I guess.

[cmw]

Well it depends whether your DVD is interlaced or not. Normally, you should be able to see interlacing with bare eyes fairly quickly (especially in scenes with much movement). If you DVD source is already progressive, there is no need to deinterlace (thus saving quite some conversion time).

If it's interlaced, de-interlacing is recommended (of course, many players can de-interlace with post-processing, but it's still nicer to have progressive video) :)

[Dark Shikari]

DVDs are almost never interlaced. They are almost always telecined.

[Tack]

And even then, almost always soft-telecined.