inverse telecine vs. deinterlace in megui

[graysky]

My sources are always NTSC mpeg-2 files from a PVR-250. I've been using MeGUI to encode these to mp4 and have noticed that most other people have 24 fps where mine are 30 fps. I started reading about inverse telecine vs. deinterlacing and am confused which to use with these type of source.

I have allowed megui to analyze the files and it usually selected "interlaced" or "hybrid" and gives some options but none of the resulting videos are 24 fps. Can someone point me to a resource that will explain these and how to use them with megui?

Thanks.

[Guest]

Files from a PVR are always encoded as interlaced, i.e., without pulldown. If you capture a movie (not anime) it's likely to be pulled down for broadcast and so it will be "hard telecined" on your recording. You should invest some time in learning how to distinguish different types of video, because MeGUI, being automatic, is not always 100% correct.

[graysky]

Sounds like good advice. Can you point me to a guide that describes that? Will deinterlacing alone reduce the framerate at all or do I need to run an inverse telecine (decomb?) as well?

Thanks.

[Guest]

I've decided it is now time to write my own. Check back in a week or two. :)

Deinterlacing alone will not reduce the frame rate.

You need to determine the nature of your video before deciding on processing. I've posted the way to do this at least 5 times. Search my posting of the last few months.

[graysky]

8,900 posts! Can you narrow it down for me :)

[Guest]

8,900 posts! Can you narrow it down for me :) Not in the last several months, though.

Try this:

http://forum.doom9.org/showthread.php?p=878536#post878536

You separate the video into fields using Avisynth and then look for the signatures I described in the above post.

I'm going to make an interactive web page using Javascript that implements a flowchart for analysing your video, with links to basic concepts, etc.

[Adub]

^^
Cool! I can't wait! I have truly needed such a thing for a while, just to work out the bugs in my own understanding.

[graysky]

@neuron2: that sounds cool. In the meantime, can you post your flowchart without the javascript? I just read through the decomb tutorial and manual and think that your material would be great to augment that.

Thanks!

[plokm]

I was trying to learn this recently too, and I found this guide helpful: http://www.doom9.net/ivtc-tut.htm

[graysky]

Thanks for the link, I guess I'm more interested in the differences in some avisynth plugins:

Telecide() vs. FieldDeinterlace() vs. KernelDeinterlace vs. TDeinterlace etc.

There are a number of these out there, which is best and why :)

[graysky]

I'm going to make an interactive web page using Javascript that implements a flowchart for analysing your video, with links to basic concepts, etc.

@neuron2: how is your guide coming? I've been messing around with Decomb and LeakKernelDeint but beyond the internal docs, I have no way of knowing if what I'm doing is right :)