Have a hybrid DVD source, now what?

[theantipop]

I've been lurking around here for the past couple months trying to gather the knowledge necessary to jump into Xvid encoding. However, I seem to be another person who has jumped into the deep end of the pool as my first attempts to encode are anime. :rolleyes:

That said, I'm trying to convert the Cowboy Bebop episodes from Region 1 NTSC DVDs along with the movie and stick them all on one DVD+R DL disc for easy viewing. The movie was a breeze as it was pure film. I've been playing around with settings for the past two months and can get the episodes to look pretty good for the most part. The problem is that the show has a lot of switching between telecined and interlaced content in the middle of the episodes.

The .d2v's indicate anywhere from 75-80% FILM. Now I've tried both AutoGK and GK to try and elminate stuttering caused by improper IVTC and interlacing that was missed. AutoGK seems to do a better job than I can manage on GK (surprise :p ), but it still leaves some wavy lines on hard edges in a lot of scenes. I'll try to post a short clip that shows this when I get home, if it will help. When using GK, I have been following the guide to a fault in that I use the IVTC option under "Field Operations" everytime FILM is under 95%. This, I guess obviously, unecessarily IVTCs parts of the show that aren't telecined and I get a lot more problems than just wavy lines.

So I'm left kind of lost as to how to deal with a hybrid source. Should I just set the Field Deinterlace and not worry about wasted bits on telecined scenes? If anyone has any specific input for Cowboy Bebop region 1 discs I would appreciate it a ton. But general guidance is also helpful.

As a last note, I've found a few threads buried among the subforums here that seem to deal with what I'm running into, but they all start out at a level of discussion that I can't follow. I'm trying not to be a stupid newb, but that's how I feel reading any forum but this one...

[Guest]

Ah, my favorite. Post a source VOB fragment with hybrid content.

manono will also be along shortly, I'd guess. :)

[theantipop]

Well, while I try to find a vob fragment that shows the hybrid portions which is also small enough to allow me to host it, here is a portion of my output avi which shows the biggest (or at least the most obvious) problem I have in my encodes.

http://home.cwru.edu/~jxm178/pics/netUpload/wavylines.avi

I did more reading today of the Telecining tutorial and it seems like the decomb avisynth plugin does frame-by-frame IVTC and doesn't just blanket apply it to the whole video. If that's the case, then I think some tweaking of the avs that AutoGK chooses might solve this.

Another quick question; in DGIndex when you are playing or previewing a vob and it shows the source info to the right (Interlaced/Progressive, FILM/NTSC), is this information correct?

[theantipop]

Alright, I think I found one. The first half of the clip is 30fps telecined Film with pretty fast movement, the second portion is 30fps progressive with slow movement, but enough to tell I think.

http://home.cwru.edu/~jxm178/pics/netUpload/hybridclip.vob

Let me know if this is telling enough. On my encoded file, the beginning is kind of jittery and the second half is very smooth. Boy, the more I dig through this and try to understand it, the more confused I am getting... :confused:

[Guest]

That's not a good example. Why? Because it looks OK with Force Film. Find a section that looks bad with FF.

The interlaced/progressive indication and film percentage are accurate, but the former only tells you how the MPEG was encoded; it doesn't tell you if the content itself is interlaced or progressive. Strange but true.

[theantipop]

Well, I've uploaded another clip to the same location as above, but again, I'm not entirely convinced that it shows the problem. Without FF it is has the obvious 3:2 telecine pattern. With FF, it disappears for the most part, but there are still random interlaced frames in the second half of the clip.

Is there an easier way to tell the difference between telecine and interlacing? It seems that you would have to go frame-by-frame throughout your source in order to tell what scenes are which. I'm beginning to think that the best way for me to find a good solution is just to keep trying different settings. On the clip I've been testing, using force film with field deinterlace seems to work the best. But I'm sure that using force film will come back to bite me sooner or later. It seems I still don't know enough to provide the right information to get help.

[Guest]

Still not a great example. :)

This time the following script works fine:

MPEG2Source("E:\tmp\theantipop\hybridclip2.d2v")
AssumeBFF()
Telecide(post=0)
Decimate()

Let me just tell you what I found with Cowboy Bebop. The episodes vary enormously. Some are fine with FF alone. Some are fine with FF and FieldDeinterlace(full=false) with a high threshold to catch just stray combs (as you suggest). Some are fine with the above script. Some are fine with the above script but with post=2 and an appropriate vthresh. I would use the last mentioned for most of the episodes.

But... You will find some real 30 fps animation mixed with film in some episodes. At that point you have to choose whether to render the final output at film rate or at video rate. The hybrid handling options of Decimate can help a little but don't expect perfection.

Distinguishing video from film...tough. If it's all flagged properly and consistently, you can use Parse D2V. But if there is any hard telecined content (3:2 without flags), that will lead you astray. There are applications such as AutoGK that automate the analysis, but no freeware ones that I know of.

(BTW, the Cowboy Bebop episodes were the main torture clips I used to develop Decomb.)

[manono]

Hi-

manono will also be along shortly, I'd guess.

Hehe, but I don't know what more I can add, as you have it pretty well covered.

However, I seem to be another person who has jumped into the deep end of the pool as my first attempts to encode are anime.

And not just any anime series, but one of the most difficult. So, AutoGK does a decent enough job, but leaves you with a lot of unnecessarily deinterlaced frames? That's one of the problems. You loosen up the post processing settings, and the next thing you know you have a lot of interlaced mouths. Which is worse, aliased, shimmering lines, or left-over interlacing? Both are pretty bad, I'll grant you, but it may be one or the other. You can let AutoGK handle it, and put up with the imperfect results, since you said it does a better job with it than you can do yourself at this point. Or you master all the Decomb settings including the override files. You master Yatta. You learn and master the alternative IVTCs such as SmartDecimate, IT, and TIVTC, to see if they can do a better job with it or not. You spend countless hours experimenting and tweaking. If you're going to be encoding a lot of anime, it'll pay off in the long run, and Cowboy Bebop will have been good training. If you just want to get CB under your belt and go back to the easy stuff, then all the work may not be worth it to you.

[len0x]

Actually what is happening with AutoGK's output its not problem with deinterlacing, but rather blending of frames by Decimate's mode=3. Afaik the only other solution would be to not blend and use mode=0 (which you can force by using "force normal IVTC" hiddent option) but then you get shuttering(that is what you get in GK manually). So you can only choose between two evils :)

[theantipop]

Wow, thanks for the replies. Very useful info. I started to take a look at the decomb options available and it looks like a lot of expirementing would have to take place before I could get the anomalies down to a barely noticeable level. As manono suggested, it may not be worth my time as at this point in time, as CB is the only anime I see myself working with.

Also after taking a look at the vobs themselves, it seems that even the source isn't perfect (at least when played back in PowerDVD). It's a shame that one of my favorite shows is such a pain to work with. But thanks again for all the advice!
:thanks: :thanks: :thanks: