Could someone please explain "Encode Mode" in TMPG

[LisaB]

I understand that if I am encoding to 23.976 fps, then I'll use "3:2 pulldown when playback", so I don't have a question about when to use that one.

But, if I am doing a PAL or 29.97 encode, then I can use either "Interlace" or "Non-Interlace".

Now, if my source actually is interlaced (i.e., 2 fields of a frame are at different times), then it is probably a good idea to keep the fields separate, and use "Interlace" mode. But really, it probably wouldn't matter if I used "Non-Interlace". When my standalone DVD sees a progressive MPEG, it's just going to separate the frames into two fields and then display them at slightly different times, anyway. Of course, if I leave the separating to my DVD player, maybe the DVD player will do the separation wrong (i.e., TFF vs. BFF)...so that would be a good argument to do "Interlace"

Now, if my source is progressive, it also looks like I could use either encode mode. If I use "Non-Interlace" encode mode, then the fields are encoded as groups of two, and when my standalone sees this, it is just going to separate them into individual fields, anyway (even though the fields represent the same moment in time). So, it looks like in the case of a progressive source, I could save my DVD player a little work by actually using the "Interlace" encode mode.

So, with all the ideas above...and I hope someone will correct me if I am wrong...It looks like I should always prefer "Interlace" over "Non-Interlace". Is there any reason to ever choose "Non-Interlace"?

[j1d10t]

If your source is progressive, then it would be better to encode as progressive. Especially if your DVD player is a progressive scan, and you have a TV that supports a progressive picture (HDTV for one), instead of interlaced.