Avisynth Problems, what am I doing wrong?

[StarRats]

Ok I'm trying to convert a PAL(DVD) to NTSC, I've Ripped the DVD to Hard Drive and ran BitRate Viewer on one of the Vobs, the Results are:-

Num. of picture read: 44619
Stream type: MPEG-2 MP@ML VBR
Resolution: 720*576
Aspect ratio: 16:9 Generic
Framerate: 25.00
Nom. bitrate: 8500000 Bit/Sec
VBV buffer size: 112
Constrained param. flag: No
Chroma format: 4:2:0
DCT precision: 9
Pic. structure: Frame
Field topfirst: Yes
DCT type: Field
Quantscale: Nonlinear
Scan type: Alternate
Frame type: Interlaced
Notes:

------------------------

And I've then being using this AVisynth Script :-


LoadPlugin("C:\Program Files\AviSynth 2.5\plugins\MPEG2Dec3.dll")
mpeg2source("C:\Documents and Settings\Star\Desktop\Clad Ripped\test.d2v")
LanczosResize(720,480)
AssumeFPS(23.976, true)
ResampleAudio(44100)

The Thing is when I Use this script in Media Player a get strange horizontal lines around things moving fast in the clip, when the footage is slow its ok. at first I thought it was media player not player the clip correctly So I loaded the script into CCE and encoded and authored the DVD to disk, the finished product on a standalone player played back with the same kind of effect but worse (looked like fast moving objects had a 0.5 second trail behind them). <thats the best I can explain it

Can anyone see what I doing wrong here?

Star

[Tommyknocker]

Have you tried to change the field order?

[FOO]

I don't understand the resample audio to 44100 part.
you need 48000
Did you remember to run pulldown on the video to
make it 29.97
IIRC assumefps does more than just assume
i think it may decimate ( eat frames )

[FulciLives]

The method you are using will really only work correctly when the PAL source is PROGRESSIVE. When the PAL source is interlaced you will get the oddness that you describe.

Xesdeeni came up with a method that works very well. It is detailed on his website:

http://www.geocities.com/xesdeeni2001/StandardsConversion/

Look at the section entitled:
VI. PAL (Video) DVD (25i Fps) -> NTSC DVD (29.97i Fps)

Also this THREAD might help you out:

https://www.videohelp.com/forum/viewtopic.php?t=160433

Good Luck

- John "FulciLives" Coleman

P.S.
To use Xesdeeni's SmoothDeinterlacer you need to use AviSynth version 2.08 which can be most easily downloaded from the DOOM9 website as most other websites seem bent on the newer 2.5x version making it hard to find a download of the 2.08 version.

[adam]

As FulciLives stated, interlaced PAL conversions to NTSC are a whole different story.

Foo, he is not converting his audio in avisynth. The resample audio line is an age old workaround for a CCE bug regarding AMD chipsets. You could set the resample line to anything you want, there's not actually any audio being encoded.

Assumefps does not duplicate or decimate frames. That is what the changefps command does. Assumefps simply takes the same frames and either speeds up or slows down the rate at which they are played. Normally this is exactly what you would want to do to convert PAL to NTSC, but unfortunately it won't work for interlaced footage. You could always blend the fields first and the proceed as normal, but that will blur the image. Assuming you have a decent bitrate, FulciLive's method will be better.

[FOO]

Now I rememebr seeing the audio trick for CCE.

Just out of curiosity , what goes wrong with interlaced pal ?.
I don't see what difference it makes if the 2 fields came from
a film frame.
does interlaced PAL not originate as film ? Are the fields separated in time ?

I assume pulldown is the problem somehow

[adam]

I really don't have any first hand experience with PAL DVDs, but technically the situation is no different than with NTSC. Most theatrically released movies will be stored progressively at either 24fps (with flags to telecine to 25) or at 25fps. Short of having to deal with some field shifting, these sources are easy to deal with.

The problems occur with other types of DVDs like tv episodes, concert footage, etc... These are often shot in PAL which means that yes, the fields each represent a different point in time.

I don't doubt there are some interlaced PAL DVDs that originated as FILM, which can easily be made progressive. But you'd need to make this determination first, and I'd guess that most of the time you run across an interlaced PAL DVD, its pure interlaced, ie: not shot in FILM.

[FOO]

I have little experience with PAL DVDs except I was in London
last month and Got Tinker,Tailor,Soldier,Spy (PAL) which I've been
looking for forever. It was a episodic "made for TV" movie which
makes me suspect it may have been interlaced. (I have to check)
Anyway I converted it by slowing to 23.976 and using pulldown
without checking first. It looks OK to me

It took a lot of time. And then I put the unconverted PAL in my player
and it converted on the fly and played fine . What a dummy

[StarRats]

Ok thanks guys for the great response, but I'm still none the wiser.

FulcilLives posted a link that would help me convert this PAL interlaced DVD to NTSC >> http://www.geocities.com/xesdeeni2001/StandardsConversion/ But the link is dead.

Adam(Moderator) said this interlaced DVD (which is BO' Selecta - a Channel4 series) can be easily made progressive, but I'd need to make the determination wherever or not is pure interlaced < how do I make this determination? then what would I need to do?

What do I need to do next guys?

[FOO]

If I was doing it , just to check I would.
open a VOB with Vdub mod, select a small section
Frameserve it to TMPGenc set to :
23.976 , pulldown on playback, "do not framerate conversion" 720 x 480
and see what it looks like . author it to a DVDRW even.
a minute or two is enough

[FulciLives]

Ok thanks guys for the great response, but I'm still none the wiser.

FulcilLives posted a link that would help me convert this PAL interlaced DVD to NTSC >> http://www.geocities.com/xesdeeni2001/StandardsConversion/ But the link is dead.

Adam(Moderator) said this interlaced DVD (which is BO' Selecta - a Channel4 series) can be easily made progressive, but I'd need to make the determination wherever or not is pure interlaced < how do I make this determination? then what would I need to do?

What do I need to do next guys?

I just tried the link to Xesdeeni's site and it worked. It is a free GEOCITIES website so it wouldn't surprise me that it goes into some "downtime" from time to time.

Try it again.

Basically you need to install AviSynth version 2.08 which you can easily find in the download section of the DOOM9 website.

Then you RIP the DVD to your HDD using DVD DECRYPTER in FILE MODE and SELECT MAIN MOVIE only (if it is episodic then you could RIP each EPISODE in IFO mode).

Now run that through DVD2AVI and make sure you use version 1.76 which again can be downloaded from the DOOM9 website.

If you are going to use TMPGEnc select RGB colorspace and PC SCALE but if you are going to use CCE then select YUV colorspace and TV SCALE.

This creates a D2V project file and spits out your AC-3 audio files (demux all audio files in DVD2AVI).

Now create the followig AviSynth AVS script:

LoadPlugin("MPEG2DEC.dll")
LoadPlugin("SmoothDeinterlacer.dll")
MPEG2Source("DRIVE:\PATH\FILENAME.D2V")
SmoothDeinterlace(doublerate=true)
LanczosResize(720,480)
ChangeFPS(59.94)
SeparateFields()
SelectEvery(4,1,2)
Weave()

Make sure you put the proper DRIVE and DIR PATH for your own files. I think Xedseeni's website has the MPEG2DEC.DLL file (although I think it comes in the AviSynth package) and I know his website has the SMOOTHDEINTERLACER.DLL file.

Anyways you now simply open this AviSynth AVS file in your encoder and off you go. Make sure you use a bitrate calculator to determine the correct bitrate. The original AC-3 files do not need to be changed (except perhaps for the delay value which can be fixed with AC3 Delay Corrector). So add up the file size of the AC-3 file(s) and the running time of the converted video will be the same as the original PAL.

CLICK HERE for a BITRATE CALCULATOR

Now when this is all done you will have a M2V/MPV video file and one or more AC-3 audio fles and off you go to your DVD authoring software.

Good Luck

- John "FulciLives" Coleman

[FulciLives]

If I was doing it , just to check I would.
open a VOB with Vdub mod, select a small section
Frameserve it to TMPGenc set to :
23.976 , pulldown on playback, "do not framerate conversion" 720 x 480
and see what it looks like . author it to a DVDRW even.
a minute or two is enough

Remember if you do it THIS way in TMPGEnc you have to check the DO NOT FRAME RATE CONVERSION check mark thing. My experience though is that if the PAL is truely INTERLACED this will result in a mess of a video that will have strange INTERLACED issues EVEN on an interlaced TV. It almost ends up looking like an INTERLACED video on a PC monitor.

- John "FulciLives" Coleman

[FOO]

I believe you. I need to satisfy myself as to WHY.
My usual trick is to generate test cases with Avisynth
and process them various ways.

Note that I had a disclaimer "just to check" in there

i shall assume that interlaced PAL means that 50 FIELDs /sec
were taken with a camcorder at evenly spaced time intervals.
This would make all the fields unrelated. Then we determine the
effect of a 3:2 pulldown on that.

The Avisynth script needs to be analyzed. what does doublerate = true do ?
ChangeFPS duplicates frames
the last 3 lines just change field order i think

[FulciLives]

I believe you. I need to satisfy myself as to WHY.
My usual trick is to generate test cases with Avisynth
and process them various ways.

Note that I had a disclaimer "just to check" in there

i shall assume that interlaced PAL means that 50 FIELDs /sec
were taken with a camcorder at evenly spaced time intervals.
This would make all the fields unrelated. Then we determine the
effect of a 3:2 pulldown on that.

The Avisynth script needs to be analyzed. what does doublerate = true do ?
ChangeFPS duplicates frames
the last 3 lines just change field order i think

First let me say I didn't realize that you DID say to check mark DO NOT FRAME RATE CONVERSION otherwise I wouldn't have even bothered with that last post.

And second ... I admit that I don't 100% understand Xesdeeni's AviSynth AVS script BUT I have used it on INTERLACED PAL DVD sources and it works rather well. I do use the other method (of slowing down 25fps PAL to 23.976fps NTSC) when the PAL DVD is PROGRESSIVE but that isn't always the case.

- John "FulciLives" Coleman

P.S.
Xesdeeni's method looks rather "odd" on the computer due to some "strange" interlacing patterns but looks 100% great on a normal TV.

[FOO]

Since I have had a grand total of 2 PAL videos to deal with
I am short on experimental evidence

[FulciLives]

Since I have had a grand total of 2 PAL videos to deal with
I am short on experimental evidence

I understand. I'm into horror films and many just aren't available in NTSC so while I do have a DVD player that is region free and converts PAL to NTSC I still like to convert some of the PAL DVD discs to NTSC as the quality can sometimes be better plus I watch a lot of these movies over at a friend's house (he has a nice big screen) but he doesn't have a special DVD player like mine.

- John "FulciLives" Coleman

[adam]

Doublerate=true is just a function of the smoothdeinterlacer which tells it that the output framerate will be double the input. You've got 25 frames per second in your source. This script works by doubling this, splitting the frames into fields, selecting only certain fields to keep, then weaving those kept back together. The doublerate=true is essentially just telling the deinterlacer that this is what you are doing.

He doubled the framerate using the changefps command. If smoothdeinterlacer were being used for another purpose and you didn't need the changefps command, than you would set doublerate to false, or just leave it out.

[SLK001]

And I've then being using this AVisynth Script :-

LoadPlugin("C:\Program Files\AviSynth 2.5\plugins\MPEG2Dec3.dll")
mpeg2source("C:\Documents and Settings\Star\Desktop\Clad Ripped\test.d2v")
LanczosResize(720,480)
AssumeFPS(23.976, true)
ResampleAudio(44100)

Drop the "true" in ASSUMEFPS. Also, the RESAMPLEAUDIO trick doesn't work for Version 2.5+ - you need "real" audio tracks.

This will fix your MediaPlayer issues, but not your interlaced issues (but what you really mean is TELECINE issues). I assume that your PAL video was simply sped up FILM, which would mean no interlaced frames.

Perhaps if you told us where you obtained your source.

[StarRats]

Ok, I've gone along with FulciLives Script and Its encoding, I did a sample first and it looked fine so fingers crossed and used beSweet to stetch the audio.

And thankyou adam for explaining the smoothdeinterlacer.dll and what it actually does .o0 Was Interesting.

I've been backing up DVD's now only for a month or so , so you say I'm a newbie, was wondering if you can point me to a few sites that will explain in detail what the terms interlaced, frame based, progressive, field order etc etc, and probably most of all the difference between 29.97 and 23 fps <<I finding it hard to grasp the difference betwwen the two, why have two NTSC frames rates?, do both frame rates play on NTSC players?

I've Backed up many DVD's and try to use the best tools for the job, most work I do is mainly parrat fashioned (using guides etc) so It would be nice to know a little more on what I'm actually doing.

Ands thanks again everyone.

[adam]

SLK001 in his first post he listed BitrateViewer's stats which show the video is interlaced. Also the results he is getting in his conversions confirm this.

StarRats, a good place to start is here:
http://www.doom9.org/index.html?/synch.htm

Progressive and frame based are basically the same. A progressive sequence is just one where each frame is a whole picture. Its just a series of snapshots.

Interlacing is where you take each one of these frames and divide it into two fields. One field represents all of the odd scan lines (a scan line is 1 row of pixels) and the other field is all the even scan lines. This what field order designates, whether the first field played is the odd/top or the even/bottom field. Basically, interlacing is a method to effectively double the playback rate of the video to cope with older technology. Its necessary to prevent flicker and to make motion fluid.

NTSC only has 1 framerate and that is 29.97fps. ANYTHING that gets played back on a non-progressive tv is always played at 29.97fps. 23.976fps is called NTSCfilm and it is just an encoding technique. When you telecine film to NTSC (29.97fps) new fields are created to increase the fps. New fields in the stream mean new fields to encode, and that uses up bitrate. Also it changes the nature of your video to interlaced rather than progressive, which wreaks havoc on the encoding algorithms that most encoders use. So the solution is to essentially just take the original stream as is. Film is shot at 24fps, so all you do is slow it down to 23.976fps which is required due to drop frame. You store it on the disk at this framerate, and then imbed a flag into the stream which instructs the DVD player to telecine the movie in real time as it plays. This way you get the required 29.97fps output, but you avoid all of the inherant drawbacks that come with a telecine. Encoding in NTSCfilm is essentially a free ride, and that's why virtually all NTSC DVDs use this technique.

So when you have a progressive 25fps PAL stream it is extremely easy to convert it to NTSC. All you have to do is slow it down to NTSCfilm (23.976fps) and then add the pulldown flags which instruct the DVD player to telecine it to NTSC.

But when you have pure interlaced PAL footage there isn't any good way to do it. You can't convert to NTSCfilm unless you make the stream progressive, which involves blending fields which is never preferable. So if you instead follow the method FulciLives mentioned, you just perform a hard telecine to NTSC by repeating your existing fields, hopefully in a sofisticated enough pattern that the resulting motion looks fluid and natural.

[pijetro]

But when you have pure interlaced PAL footage there isn't any good way to do it. You can't convert to NTSCfilm unless you make the stream progressive, which involves blending fields which is never preferable. So if you instead follow the method FulciLives mentioned, you just perform a hard telecine to NTSC by repeating your existing fields, hopefully in a sofisticated enough pattern that the resulting motion looks fluid and natural.

Actually, I've found it pretty fluid, in that if the encoder was instructed to do an interlaced encode (no zigzag or progressive pattern), then the video turns out to be very fluid. Much like one would encode a 29.97fps interlaced source, except, this one is 23.976fps with pulldown added..

From my experiences, the only difference that PAL progressive, and PAL interlaced conversions have, is the encoding method...

I don't seem to see where it's carved in stone that 23.976fps has to be a progressive type snapshot of every scene..Even if it is a snapshot of two different scenes, as long as you didn't encode progressively, what should it matter?? This is referring to NTSC television mind you, and not a monitor...

We can get into theory here, but it works for me.

As for interlaced and progressive PAL footage goes, I don't trust what DVD2AVI or BitrateViewer tells me. I simply do a separatefields() command in AviSynth, and watch frame by frame what VirtualDub shows.

[adam]

The 3:2 pulldown flag is only supported if the prog_frames flag is set to true, or in other words if you set the encoder to progressive. It IS carved in stone, ala the DVD specification. Maybe you had luck with ~24fps interlaced material with 3:2 pulldown flags applied, but the fact is that it is not DVD compliant and on most hardware players it will not play back properly.

[FulciLives]

Ok, I've gone along with FulciLives Script and Its encoding, I did a sample first and it looked fine so fingers crossed and used beSweet to stetch the audio.

I think you will be happy with the end result. Please post back here to let us know

If I didn't say it before let me say it now ... this method looks "odd" playing it back on your computer monitor becuase the converted NTSC video will have an "odd" interlaced pattern BUT once you burn it to DVD and watch it on a normal NTSC TV it will look fine and you should find the motion is smooth (or smooth enough).

ALSO PLEASE NOTE:
This method does not require the audio to be changed with BeSweet. You can use the original PAL AC-3 without changing it. You only need to change the length of the audio when you do the OTHER conversion method where you slow down 25fps to 23.976fps

- John "FulciLives" Coleman

[StarRats]

Encoding has finished using Fulcilives script and I must say it looks very nice, I was just about to post another message regarding the audio as I was using BeSweet to to change it to 25 > 29 but they didn't sync, then I read Fulcilives last post (doh!).

I was wondering why the AC3 file doesn't need to be changed when using this method, I don't understand that.

P.S

I'm just about to burn to disk and I'll let you guys know what the finished product is like.

Thanks
Star

[adam]

The audio does not need to be adjusted for the same reason that the audio does not need to be adjusted when converting 23.976fps to 29.97fps... The increase in speed comes not by changing the rate of play, it comes by creating new frames each second.

Basically, you started out with 25 frames each second. In this conversion what you have essentially done is created new intermediate frames which fit in between existing ones. So even though there are more frames each second, you still have the same number of total seconds in your film. So, your film still starts and ends at the same points, and the same is true of your audio so they sync even though there are new frames inserted throughout.

[StarRats]

Right guys, I've burned to DVDr and the finished product is great, I just like to thank Adam for his explanations in to the different means of each task I carried out, FulciLives for providing the script and to and everyone else for there input.

I can honestly say I've learnt more from this thread than 2 weeks of reading, I suppose this brings the thread to an end, so manys thanks again.

I hope other people will benefit from this thread when converting Interlaced PAL to NTSC

Many thanks

Star

[FulciLives]

Right guys, I've burned to DVDr and the finished product is great, I just like to thank Adam for his explanations in to the different means of each task I carried out, FulciLives for providing the script and to and everyone else for there input.

I can honestly say I've learnt more from this thread than 2 weeks of reading, I suppose this brings the thread to an end, so manys thanks again.

I hope other people will benefit from this thread when converting Interlaced PAL to NTSC

I am constantly trying to tell people about this method but they insist that slowing down interlaced PAL to 23.976fps works ... but it does not ... plus most seem to think that it is "too much" for them to learn AviSynth etc.

Glad it worked for you and hopefully some other people will see this THREAD too.

- John "FulciLives" Coleman

[StarRats]

Shite I spoke to soon! while I was writing my last post I was burning to disk (jumped the gun), but once I played the DVD the result was odd, the quality and sound sync was perfect but any fast movement didn't seem to be smooth enough, although the DVD was watchable after a while it became annoying.

Any ideas?

Thread re-opened

P.S

I'm sure when this thread is complete I'll be a interlaced PAL to NTSC God

[FOO]

OK deinterlace it , and do the normal method just for grins

[FulciLives]

Shite I spoke to soon! while I was writing my last post I was burning to disk (jumped the gun), but once I played the DVD the result was odd, the quality and sound sync was perfect but any fast movement didn't seem to be smooth enough, although the DVD was watchable after a while it became annoying.

Any ideas?

Thread re-opened

P.S

I'm sure when this thread is complete I'll be a interlaced PAL to NTSC God

Damn you SUCK and here I thought you had it :P

From your first post I take it you used CCE correct? I only recently started using CCE and the last time I did a PAL DVD this way (from INTERLACED source) I used TMPGEnc. Not sure what differene if any that makes.

What settings I guess in CCE did you use?

- John "FulciLives" Coleman