Welcome to Doom9's Forum, THE in-place to be for everyone interested in DVD conversion.

Before you start posting please read the forum rules. By posting to this forum you agree to abide by the rules.

 

Go Back   Doom9's Forum > Capturing and Editing Video > Avisynth Usage

Reply
 
Thread Tools Search this Thread Display Modes
Old 29th October 2002, 01:14   #1  |  Link
wfn1
teh 8bit fool
 
wfn1's Avatar
 
Join Date: Oct 2002
Posts: 266
hybrid source with 2% NTSC / decomb questions

I've been trying to transcode(CCE) Fellini's 8 1/2 (Criterion edition) and since it's my first experience with a hybrid source I thought I'd ask the omniknowledgeable forum members a few questions.

1) When encoding a hybrid source with relatively low action, at what % of NTSC should I start considering decomb.dll? (in my example it was 98%film 2%ntsc for the actual movie) Since I thought the transfer was not perfect to begin with I frameserved it with DVD2AVI with "no field order" and ran it through Telecide(post=false) Decimate(mode=1,threshold=50) in my .avs script.

2) When do I want to use Telecide() vs. Telecide(post=false), I've been told that there is no rule of thumb but supposedly post=false works better on cleaner/more modern transfers.

3) Is it normal for the end result .mpv to come out with drop_frame flag set? I had to do a -nopulldown -drop_frame false to import chapters in Maestro as it does not like the drop for that. (later reverted back to dropped for subtitle sync)

Sorry, if this belongs in a newbie forum and thank you for any feedback.
wfn1 is offline   Reply With Quote
Old 29th October 2002, 02:46   #2  |  Link
JohnMK
Registered User
 
Join Date: Sep 2002
Location: Seattle
Posts: 551
Re: hybrid source with 2% NTSC / decomb questions

Quote:
Originally posted by wfn1
I've been trying to transcode(CCE) Fellini's 8 1/2 (Criterion edition) and since it's my first experience with a hybrid source I thought I'd ask the omniknowledgeable forum members a few questions.

1) When encoding a hybrid source with relatively low action, at what % of NTSC should I start considering decomb.dll? (in my example it was 98%film 2%ntsc for the actual movie) Since I thought the transfer was not perfect to begin with I frameserved it with DVD2AVI with "no field order" and ran it through Telecide(post=false) Decimate(mode=1,threshold=50) in my .avs script.
No Field Operation, you mean. You need to use mode=0 or 2, not 1. 1 leaves it at 29.970. I believe something like this might be better:

Telecide(guide=1,post=false)
Decimate(mode=2) or (mode=0)

Neuron2, however, cautioned me against using mode=2, but his help file in decomb says this is better for IVTC of 3:2 pulldown material. Neuron2, care to clarify?


Quote:
2) When do I want to use Telecide() vs. Telecide(post=false), I've been told that there is no rule of thumb but supposedly post=false works better on cleaner/more modern transfers.
For most DVD hollywood feature movies you shouldn't need to post process, but I do just in case anyway. It doesn't hurt. Yeah it slows it down a little bit, but oh well, CPUs are fast. But you really shouldn't need to use decomb on this movie. DVD2AVI Forced FILM can be trusted at this percent FILM.

Quote:
3) Is it normal for the end result .mpv to come out with drop_frame flag set? I had to do a -nopulldown -drop_frame false to import chapters in Maestro as it does not like the drop for that. (later reverted back to dropped for subtitle sync)

Sorry, if this belongs in a newbie forum and thank you for any feedback. [/B]
Can't answer your last question, sorry.

Last edited by JohnMK; 29th October 2002 at 04:45.
JohnMK is offline   Reply With Quote
Old 29th October 2002, 06:55   #3  |  Link
wfn1
teh 8bit fool
 
wfn1's Avatar
 
Join Date: Oct 2002
Posts: 266
thanks!

Thanks for your reply, JohnMK!

Quote:
I believe something like this might be better:

Telecide(guide=1,post=false)
Decimate(mode=2) or (mode=0)
So, a script like that should leave me with 24fps FILM if I understood you correctly? That would actually be quite nice and I would not have to waste the unnecessary bandwidth in CCE. I'm afraid to use mode=2 though, just in case it cuts out something useful.

Would you say that mode=1 would be the most safe/almost loseless option for hybrid sources? Or am I just full of sh*t?

Also, if you happen to know if there is a quick way to decide between
"mode=0", "mode=2" and "mode=1, threshold=50" by stepping through the fragment in question in VDub with telecide(post=false) like it suggests in IVTC guide?

I would really like to hear what Neuron2 has to say about it, after all if a certain way is better for hybrid than what's in Doom9's decomb.dll guide, might as well amend it or offer it as another option.
wfn1 is offline   Reply With Quote
Old 29th October 2002, 09:36   #4  |  Link
Richard Berg
developer wannabe
 
Richard Berg's Avatar
 
Join Date: Nov 2001
Location: Brooklyn, NY
Posts: 1,211
I don't do DVD rips so I can't make a direct comparison, but one of the TV shows I'm capping right now (Andromeda) has about the same ratio (5% video source / 95% film source). I decided to go with full-out Telecide(guide=1).Decimate(mode=2) -- terrific output on the film material, and while the CGI sections obviously get choppy they're no worse than any other method I tried short of going to 60fps.
Richard Berg is offline   Reply With Quote
Old 29th October 2002, 17:19   #5  |  Link
wfn1
teh 8bit fool
 
wfn1's Avatar
 
Join Date: Oct 2002
Posts: 266
trying to avoid choppyness

hmm, that's what i'm trying to avoid at all costs, I want the copy to be as close to the original as possible without having to split to 2 DVD-Rs. So, I guess I'll play more with mode=0 or mode=1, threshold setting. Thanks for your input!
wfn1 is offline   Reply With Quote
Old 29th October 2002, 18:05   #6  |  Link
JohnMK
Registered User
 
Join Date: Sep 2002
Location: Seattle
Posts: 551
Actually in my experience mode=1 on FILM material is a bad idea. Telecide spits out progressive frames + one duplicate in a series of 5. Mode=1 tries its best to make that duplicate a blend of the two surrounding progressive frames, but doesn't seem to ameliorate the problem altogether.
JohnMK is offline   Reply With Quote
Old 29th October 2002, 19:20   #7  |  Link
manono
Moderator
 
Join Date: Oct 2001
Location: Hawaii
Posts: 7,406
Hi-

Listen to JohnMK. You don't have hybrid material. So, don't use Mode=1. It's just a movie and shouldn't have any true interlaced video in there. Telecide().Decimate() should work fine.
manono is offline   Reply With Quote
Old 29th October 2002, 19:24   #8  |  Link
wfn1
teh 8bit fool
 
wfn1's Avatar
 
Join Date: Oct 2002
Posts: 266
hmmmm

by that logic i can just serve it as 'force FILM' in DVD2AVI though...
wfn1 is offline   Reply With Quote
Old 29th October 2002, 19:37   #9  |  Link
DJ Bobo
Encoding Dinosaur!
 
DJ Bobo's Avatar
 
Join Date: Oct 2001
Location: Europe
Posts: 1,668
That's it, just use "Force Film" in DVD2AVI.
DJ Bobo is offline   Reply With Quote
Old 29th October 2002, 19:42   #10  |  Link
JohnMK
Registered User
 
Join Date: Sep 2002
Location: Seattle
Posts: 551
Quote:
Originally posted by manono
Hi-

Listen to JohnMK. You don't have hybrid material. So, don't use Mode=1. It's just a movie and shouldn't have any true interlaced video in there. Telecide().Decimate() should work fine.
As DJ Bobo states, just use Forced FILM.

Now, for something completely off-topic, what's the meaning of this contained within the DecombHelp.html file?

About mode=2:

"Note that for the most reliable IVTC of 3:2 pulldown material, you should use pattern guidance together with this mode of decimation."

Exactly how necessary is this? From what I've seen, neuron2 is telling us to avoid mode=2 except for anime.
JohnMK is offline   Reply With Quote
Old 29th October 2002, 19:49   #11  |  Link
wfn1
teh 8bit fool
 
wfn1's Avatar
 
Join Date: Oct 2002
Posts: 266
modes

please share your wisdom on the:

Quote:
Also, if you happen to know if there is a quick way to decide between "mode=0", "mode=2" and "mode=1, threshold=50" by stepping through the fragment in question in VDub with telecide(post=false) like it suggests in IVTC guide?
subject. Thanks!
wfn1 is offline   Reply With Quote
Old 29th October 2002, 20:32   #12  |  Link
Asmodian
Registered User
 
Join Date: Feb 2002
Location: San Jose, California
Posts: 4,406
If you notice some interlacing after the force film (the 2% that didn't have the pulldown flags) then you can use decomb to IVTC but if there is no visible interlacing then force film will encode a bit faster. I noticed some interlacing on some Sherlock Holmes DVD's when using force film when the % film was around 98%, while decomb gave me perfect progressive video (but I had post=true so it might have cleaned up a few interlaced frames, I didn't look through it that closely).
just my 2 cents
Asmodian is offline   Reply With Quote
Old 30th October 2002, 00:23   #13  |  Link
LB
Registered User
 
Join Date: Feb 2002
Posts: 285
Try it

Try it, the ivtc filter that is. It doesn't work on all sources. It's strange. If decomb or tmpg work, then usually IT wont, whereas if decomb or tmpg don't ivtc the source well, then IT usually works. There is nothing to configure except whether the source is top or bottom field order. But I tried EVERYTHING on a few Region2 dvds I have and NOTHING worked to remove the interlacing on certain hybrid parts, BUT when I tried "IT" 95% of the interlaced frames were removed, NO blending! Give it a shot, it's definatly worth trying out. Search the threads for like IT and IVTC and ye shall find.

LB
__________________
1. CPUs:2x2.4_LV @ 3.6 (16x229) 1.5v MB:DH800 HS:E3W-NPTXS-04 CRT:FP2141SB HDs:8x147gbU320 1x36gbU320 2x250gbIDE GPU:X800XT DVDRW:PX-712A PSU:2xAntec 550w CASE:PC-78
2. CPUs:1x2.4A @ 3.0 MB:SFF SB61G2BV3 CRT:KVM(see above) HDs:2x120gb IDE GPU:Ti4600 DVDRW:A107
3. Notebook:T40p
LB is offline   Reply With Quote
Old 30th October 2002, 10:26   #14  |  Link
JohnMK
Registered User
 
Join Date: Sep 2002
Location: Seattle
Posts: 551
I don't think IT would make a good keyword. It falls below the minimum length and it's (!) a very common word.
JohnMK is offline   Reply With Quote
Old 30th October 2002, 10:40   #15  |  Link
Wilbert
Moderator
 
Join Date: Nov 2001
Location: Netherlands
Posts: 6,364
See our FAQ for download (Q28). We are still missing a proper documentation about this plugin.
Wilbert is offline   Reply With Quote
Old 30th October 2002, 18:16   #16  |  Link
manono
Moderator
 
Join Date: Oct 2001
Location: Hawaii
Posts: 7,406
Hi-

by that logic i can just serve it as 'force FILM' in DVD2AVI though...

Your's is faulty logic. A full strength IVTC will work on any material (more or less) that was telecined in the first place. Force Film will only work perfectly on telecined material where all the flags have been set properly. Of all the telecined material that I see, about 90% or so must be IVTC'd, and if only Force Filmed will leave behind at least some interlacing or jerkiness (and at percentages up to 99%). The only time that Force Film is guaranteed to work is when it shows as Film (100% Film). The guides say to Force Film when the Film percentage is equal to or greater than 95%. That may work, but isn't guaranteed.

...quick way to decide between "mode=0", "mode=2" and "mode=1, threshold=50"

For the purposes of your movie, you can forget Mode=2, as it's mainly for anime. Make your .d2v with no Field Operation, open it in GKnot, and go to the places that show in DVD2AVI as interlaced or NTSC. Step through it frame by frame and if you see interlacing in every frame, then it's interlaced and Mode=1 may be the answer if you can't live with the jerkiness resulting from bringing it down to 23.976fps. If it shows the usual 2 interlaced frames in every 5, then IVTC it. Or doing it your way, make the .avs with Telecide(Post=False) and no Decimate(5). Go to those same places, and then you're looking for no interlacing and one duplicate frame in every 5.
manono is offline   Reply With Quote
Old 30th October 2002, 18:24   #17  |  Link
wfn1
teh 8bit fool
 
wfn1's Avatar
 
Join Date: Oct 2002
Posts: 266
thanks!

thanks for your help, manono!

Quote:
If it shows the usual 2 interlaced frames in every 5, then IVTC it
Should I IVTC it in DVD2AVI or would decimate(mode=0) would be better?
wfn1 is offline   Reply With Quote
Old 30th October 2002, 18:49   #18  |  Link
manono
Moderator
 
Join Date: Oct 2001
Location: Hawaii
Posts: 7,406
Hi wfn1-

You're fast on the reply-you must want to get this (great) movie finished. Ordinarily, when speaking of IVTC, we are referring to the "full strength" solutions such as Decomb, GreedyHMA, IVTC2.2, or IT. Force Film in DVD2AVI is a somewhat "weaker" solution that only follows the flags, and doesn't use the "brute force" methods of field matching or pattern detecting.

But to answer the question-to be absolutely safe, I'd use Decomb if I were you. Force Film may work, but I've been burned too many times by using Force Film and then finding interlaced frames afterwards. Force Film is faster (particularly if the deinterlacer is turned on in Telecide()), but Decomb is surer.
manono is offline   Reply With Quote
Old 30th October 2002, 20:26   #19  |  Link
wfn1
teh 8bit fool
 
wfn1's Avatar
 
Join Date: Oct 2002
Posts: 266
confirmation.

so in other words if i want to IVTC it I would be better off with

Telecide(guide=1,post=false)
Decimate(mode=0)

rather than DVD2AVI's force film.

btw, I made 2 copies of the movie, one with

Telecide(post=false)
Decimate(mode=1,threshold=50)

lost some bandwidth on the encoding part since it's 29.97 fps.

and one with just force FILM in DVD2AVI, I'll watch both tonight and let you know which one turned out better. I will also try to use decomb to IVTC and see if the end result is better then DVD2AVI's force FILM.

Cheers!
wfn1 is offline   Reply With Quote
Old 30th October 2002, 21:17   #20  |  Link
Guest
Guest
 
Join Date: Jan 2002
Posts: 21,901
@JohnMK

Mode 0 vs 2: If in a cycle you have multiple different strings of duplicates, e.g., n d d n d, where n is a new frame and d is a duplicate, mode 0 will take the frame that is most similar to its predecessor and not the one that is part of the longest string of duplicates. For normal films, these sequences are rare and it won't matter; use mode=0. For animations that are animated by duplicating or triplicating (or worse) each frame, you need to decimate from the longest duplicate sequence to avoid causing jerkiness; use mode=2.

I need to correct the statement in my help file that you referred to. Thank you for pointing it out.

@wfn1

You might also consider using Forced Film but passing the result through FieldDeinterlace(full=false). I know my hero manono is holding his hands over his ears and grimacing, but you may find it satisfactory for your purposes.

Last edited by Guest; 30th October 2002 at 21:19.
Guest is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +1. The time now is 08:12.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.