ok i seriously cant figure out how to remove interlacing

nemesis310 · Post by **nemesis310** » Fri Dec 12, 2003 3:16 pm

yes i read that one guide that everyone links to when people ask questions, but i couldnt understand the part about how to use that Inverse Telecine method to remove interlacing. it seemed like it was just explaining why it worked but not actually how to do it. can someone tell me how to do it?

Scintilla · Post by **Scintilla** » Fri Dec 12, 2003 3:57 pm

Example from my own hard drive:

MPEG2Source("K:\source\D2Vs\flcl1.d2v")
<b>Telecide()
Decimate(cycle=5)</b>

There's your basic IVTC script. This gives you (hopefully) a progressive 23.976 FPS video. Personally, I include the line "AssumeFPS(24)" in my scripts, because I work with Adobe Premiere, which has no support for 23.976.

SQ · Post by SQ » Tue Dec 16, 2003 2:45 pm

I could never figure out how to do inverse telecline, so I just deinterlace using VirtualDub, after I've made the actual video.

You can do this by importing your video, going to "Video", then "Filters", "add", "Deinterlace". The auto-selected option is what you want.

Then you export your video, and it should be deinterlaced. ^^

danielwang · Post by **danielwang** » Tue Dec 16, 2003 8:38 pm

SQ wrote:I could never figure out how to do inverse telecline, so I just deinterlace using VirtualDub, after I've made the actual video.

You can do this by importing your video, going to "Video", then "Filters", "add", "Deinterlace". The auto-selected option is what you want.

Then you export your video, and it should be deinterlaced. ^^

Good idea, and works in decent programs such as AE and Premiere.

But, I'd hate to think what would happen if CINERELLA! the frame order CINERELLA! were CINERELLA! wrong CINERELLA!.

trythil · Post by **trythil** » Tue Dec 16, 2003 9:25 pm

danielwang wrote: But, I'd hate to think what would happen if CINERELLA! the frame order CINERELLA! were CINERELLA! wrong CINERELLA!.

Umm, you're retarded. Frame order has nothing to do with anything.

Now if you were talking about field order, there would be some discussion.

The Cinelerra deinterlace filter is not sensitive to field dominance. The inverse telecine function is. That's hardly a problem, though.
Field order is a pain to automatically determine or work around, and the programmer is usually better off letting a human eye do it. In the case of some algorithms (e.g. Telecide algorithm, KernelDeint algorithm) it's more accurate if the field order is explicitly (and correctly) specified.

danielwang · Post by **danielwang** » Tue Dec 16, 2003 11:50 pm

Oops my bad. I meant the order of how the frame data is encoded as dependent:

data like IBBBBPPPP (frame order) and Top bottom AA AB BC CD (field order I think) etc are lost on conversion right?

So all that's left is the keyframe info and the software just follows in that order? That'll make for some VERY SLOW seeking!

>.> I wanna frame independent codec like Huffyuck

trythil · Post by **trythil** » Wed Dec 17, 2003 12:11 am

danielwang wrote:Oops my bad. I meant the order of how the frame data is encoded as dependent:

data like IBBBBPPPP (frame order) and Top bottom AA AB BC CD (field order I think) etc are lost on conversion right?

So all that's left is the keyframe info and the software just follows in that order? That'll make for some VERY SLOW seeking!

>.> I wanna frame independent codec like Huffyuck

Um, you're retarded. And you're wrong again.

trythil · Post by **trythil** » Wed Dec 17, 2003 12:33 am

trythil wrote:
danielwang wrote:Oops my bad. I meant the order of how the frame data is encoded as dependent:

data like IBBBBPPPP (frame order) and Top bottom AA AB BC CD (field order I think) etc are lost on conversion right?

So all that's left is the keyframe info and the software just follows in that order? That'll make for some VERY SLOW seeking!

>.> I wanna frame independent codec like Huffyuck
Um, you're retarded. And you're wrong again.

To continue:

I had a long explanation of exactly why you were wrong here.

Then I realized that I could use the following argument.

I use this software; I know what it's like. I know that everything you're writing is wrong. I know that no data is lost in indexing. I know that seeking in indexed MPEG-2 material is as fast, if not faster, than seeking in an MPEG-2 indexed with DVD2AVI via AVISynth. I know that field order information is not lost unless I explicitly remove the field dominance. I know that I have five videos that can back me up on this. I know that I am currently rendering a sixth video that can also serve as a testament to my claim that Cinelerra works just fine and doesn't do anything that you said it does.

So just shut the hell up until you know what you're talking about.

This is one place where anecdotal evidence comes in very handy.

---

Back on topic:

Deinterlacing is not the same as inverse telecining. This is not merely a difference of words; it reflects a difference in procedure (and sometimes product) as well.

You can think of an inverse telecine algorithm as an algorithm that detects the interlaced frames in a given n-frame sequence and reconstructs an equivalent progressive frames based on that information. This may entail changing the frame rate, deleting frames, deinterlacing algorithms, etc.

Deinterlacing does not do that. What deinterlacing basically does is remove the time difference between fields in interlaced video, which, if done correctly, makes the video more pleasant to view on a progressive-scan device, i.e. most modern CRTs, flat-panels, progressive-scan TVs, etc.

You can recover a progressive-frame stream from telecined video using either method, but inverse telecine, if you can do it, has the following potential advantages:
- Less frames to encode, therefore more bits can be allocated per frame at a given bitrate.
- Smoother motion than what may be attainable via deinterlacing.

This is all stuff that you've probably read before, but I feel it necessary to emphasize the difference between the two procedures. They do not produce similar output, nor are they the same thing.

SQ · Post by SQ » Wed Dec 17, 2003 1:17 pm

.... Interesting. I never knew that. Thanks, Trythil. ^^