Top or Bottom?

[rrrrob]

Trying to understand what the "Field Order" function does when encoding DVD video. I have the option of bottom or top field first. I read DV is always bottom field first and analog video is top field first. I am encoding DVD disks for standard televisions.

What is this top/bottom field option referring to? The interleaved refresh phase or what? I can't seem to tell any difference when I encode them both ways. Thanks!

[blutach]

Interlaced, BFF is fine for MPEG-2 to be played on a standard TV.

Progressive is TFF (usually played on PCs)

See http://forum.doom9.org/archive/index.php/t-47393.html

Regards

[rrrrob]

thanks! but that thread (the one you pointed out) claims commercial DVDs are top field first, and i mentioned someone said analog video was top field first (standard CRT television is analog, isn't it?), so wouldn't top field first be the better choice for my DVDs?

[anonymez]

most content you will encounter, including interlaced commercial DVDs, is TFF, and correct, DV is BFF.

Progressive is TFF

progressive content is in frames, not fields, so it's neither

I can't seem to tell any difference when I encode them both ways

decoding with the wrong field order usually results in stuttering and/or nasty artefacts. doesn't really matter which you pick in the encoder, but best to go with TFF in this case

[blutach]

A lot of DVDs are encoded progressive, so are TFF.

As bb said, why not try encoding a short segment in both and seeing how they play on your TV (not your PC monitor).

Regards

[anonymez]

TFF = Top Field First. progressive content is encoded as frames, not fields; TFF/BFF does not apply to progressive content

[ed klein]

There is an option in TMPGEnc Plus to set top field first or bottom field first before you encode.

Select the option top field first and run it thru the test, if the movie is not smooth or jerky then change the option to bottom field first and then encode.

[rrrrob]

it was the same either way...