TMPGEnc Plus interlace or non-interlace?

[xycer]

first off, i basically only use TMPGEnc Plus to encode videos to MPEG2 DVD format. i know what the difference is between interlaced and non-interlaced (progressive), but i'm wondering, how do you know if the source is interlaced or not? will TMPGEnc automatically detect whether its interlaced or not? and if the source IS interlaced, and i select non-interlace for the output, will there be any problems?

[yoda313]

You should be able to use gspot or avicodec to tell.

Also you can use a software dvd player like powerdvd and use the information tab - it will tell you the resolution and framerate and progressive/interlace status.

[daamon]

but i'm wondering, how do you know if the source is interlaced or not?

Sorry yoda313, but I'm not sure that GSpot or AVICodec provides that information - unless it's changed recently.

@ xycer: Do you have source files that you're particularly interested in? i.e. are you asking about AVI from your miniDV cam? Or is is files in general that could come from anywhere?

will TMPGEnc automatically detect whether its interlaced or not?

Yes, I believe it does automatically detect this from the source.

and if the source IS interlaced, and i select non-interlace for the output, will there be any problems?

Only if you want to play the end product (output) on a standard TV - which is interlaced. The rule is, select interlaced or de-interlaced according to what you're going to be watching the output on.

[xycer]

nah, just in general.

i have both a progressive setup (HDTV), and an interlaced setup (my small CRT TV in my room). i probably watch on both equally.

but arent all DVD movies encoded to progressive, or interlaced? i think ive made the output progressive before with one of my avi files, and it played fine on my interlaced setup.

[yoda313]

but arent all DVD movies encoded to progressive, or interlaced?

Most tend to be progressive I believe. But a lot of the older tv shows on dvd are most likely interlace.

[xycer]

so if most DVD's are progressive, if i encode to progressive, i shouldnt have any problems, even with a non-HDTV or EDTV right? or simply put, it would be ok to encode to progressive with all videos, even if the source is interlaced?

[manono]

...it would be ok to encode to progressive with all videos, even if the source is interlaced?

Don't be absurd. Of course not. And TMPGEnc won't tell you if the source is progressive or interlaced. It'll only tell you how it was encoded originally. There's a difference. The only way to tell with confidence if it's really interlaced is to look at the frames. Even movies for NTSC are frequently encoded as interlaced, already telecined 29.97fps encoded as interlaced. Lots of anime, DVD extras, and TV show DVDs are the same way. You make them progressive (without an IVTC), and you're in big trouble if you try and watch it on your HDTV.

[xycer]

...it would be ok to encode to progressive with all videos, even if the source is interlaced?

Don't be absurd. Of course not. And TMPGEnc won't tell you if the source is progressive or interlaced. It'll only tell you how it was encoded originally. There's a difference. The only way to tell with confidence if it's really interlaced is to look at the frames. Even movies for NTSC are frequently encoded as interlaced, already telecined 29.97fps encoded as interlaced. Lots of anime, DVD extras, and TV show DVDs are the same way. You make them progressive (without an IVTC), and you're in big trouble if you try and watch it on your HDTV.

umm, how was i being ubsurd? i was not stating a fact, but asking a question. based on the information given to me, it seemed as if it was ok.

The only way to tell with confidence if it's really interlaced is to look at the frames. Even movies for NTSC are frequently encoded as interlaced, already telecined 29.97fps encoded as interlaced. Lots of anime, DVD extras, and TV show DVDs are the same way.

how am i supposed to tell by looking at the frames?

[manono]

No, no one said anything to lead you to conclude it was OK to encode interlaced material as progressive. While it's OK to encode progressive material as interlaced (almost all PAL DVDs of movies are like this), it's not OK the other way around. When done you'll have an incorrect progressive flag. What does that mean? Here, check this out:

http://www.hometheaterhifi.com/cgi-bin/shootout.cgi?function=search&articles=all

About halfway across the top you'll see a column labelled "Incorrect Progressive Flags". Follow it down, and although near the top you'll see that the best DVD players will spot it and deal with it correctly, as your eye goes down, more and more of the boxes are in red. What happens? If played on an interlaced TV set, nothing happens. If played on an HDTV, you'll get all the interlacing showing up, and it's not a pretty sight. For more information, read this:

http://www.hometheaterhifi.com/volume_10_1/dvd-benchmark-guide-to-progressive-scan-sho...ogressive_Flag

Scroll down about half way to the Incorrect Progressive Flag section. I can't make it go to the right place.

how am i supposed to tell by looking at the frames?

You'll see interlacing. You know what that looks like, right? Fine, black, parallel, horizontal lines visible during movement? You can play the DVD in PowerDVD with the deinterlacer set for Weave, or turned off. Find a place with movement/motion, first pause it, and then advance a frame at a time. With progressively encoded DVDs (which is most of them, for movies anyway) all the frames will look nice. If interlacing is present, you'll see it, either every frame for pure interlace DVDs, or in 2 frames out of 5 for hard telecined movies. Most other players can do something similar. Or you can open a Vob in VDubMod and do the same thing. Advance a frame at a time where there's motion. If you see interlacing every frame, it's an interlaced DVD. If you see interlacing in 2 of 5 frames, it can be IVTC'd and then encoded progressively with pulldown applied afterwards. If you don't see any interlacing at all, then it's been progressively encoded.

[jagabo]

how am i supposed to tell by looking at the frames?

See this post:

https://forum.videohelp.com/viewtopic.php?p=1456753#1456753

for a sample of interlace comb lines.