Framerate conversion

[Truman]

I guess the only reason to change the framerate is that you downloaded the source.
The following little guide should help you to cange the framerate from 23.976 to 25 fps or vice versa.
If you have a 29.97 fps or an odd framerate like 15 or 20 fps, I dont know a good solution, then you have
to do a real framerate conversion, so you will end with jerky playback. Well, some people do not even notice
that, but since a real framerate conversion is done by duplicating / deleting frames, the final MPEG wont
play smooth.

Start with decompressing the audio. Load the .avi or .mpg into VirtualDub, select file > save WAV
(PCM uncompressed).

1. Video

1a. Video conversion with TMPGEnc.
Load the source file as video source, load a template, go to the advanced tab. Check "do not framerate
conversion"



Set whatever you want else, select "video only" and start conversion.

1b. Frameserve with Avisynth

Avisource("c:..dir..filename.avi")#PALsource
#BilinearResize(448,254,1,0,638,272)
#AddBorders(16,113,16,113)
AssumeFPS(23.976)

Avisource("c:..dir..filename.avi")#NTSCsource
#BilinearResize(448,306,1,0,638,272)
#AddBorders(16,135,16,135)
AssumeFPS(25)

If the source is MPEG-1 use DirectShowSource instead of AviSource.
If the source is MPEG-2, create a DVD2AVI project and get the mpeg2dec plugin for Avisynth.

LoadPlugin("c:..dir..mpeg2dec.dll")
mpeg2source("c:..dir..filename.d2v")
#BilinearResize(448,254,1,0,638,272)
#AddBorders(16,113,16,113)
AssumeFPS(23.976)

Load the .avs as video source into your favorite MPEG encoder.

1c. Frameserve with VirtualDub
Open the source file in VirtualDub. If the source is MPEG-2,
create a dvd2avi project and convert
it with VFAPIconv. Then open the fake *vfapi.avi in VirtualDub.

Select video > framerate.., change the framerate



Add all filters you like and start the frameserver. Load the *.vdr resp. the *vdr.avi as video source
into your favorite MPEG encoder.

2a.Audio with BeSweet

Start the BeSweet GUI. Set the path to BeSweet.exe[1], input[2]and output[3] file.
Select the output format[4], check downsampling if necessary[5].
At the OTA section change framerate[6] from 960 to 1001 (23.976 to 25 fps). BeSweet does not support 1001 to 960
(25 to 23.976 fps) yet. You may use Cool Edit.



Go to the SSRC tab. Select options.



At the 2Lame select the output options.



Back to the BeSweet tab press WAV to MP2.

3. Multiplex

2b.Audio with CoolEdit

Open the WAV audio in CoolEdit, select transform > time / pitch > stretch



You see the origininal length of the in seconds, here 559.096 = 9:19.096 x 25fps= 13977 frames



13977 frames / 23.976 fps = 582.96 = 9:42.96. Compare the time to the time of video file.



Press OK. It takes a couple of monutes.



Save as WindowsPCM (*.wav). Continue with downsampling (CoolEdit or BeSweet[ssrc]) and audio
conversion, e.g. with BeSweet.

3. Multiplex

[Goring]

What an excellent guide!!! I always strayed away from framerate conversions since they always threw the audio out of synch, but it seems as though this problem has been effectively solved. Bravo- now it will be easy to convert from NTSC <-> PAL and be able to fix bizzarre (sp?) framerates. Thanks for the guide- Aaron

[Warrior]

I discovered a much easier way to convert NTSC to PAL. I used Virtual Dub as a frameserver and TMPGEnc as client for the new encoding.

That's all

[cramon]

What went wrong?
I stretched the audio with cool edit, as you described.
But now i got a' audiofile, filled with voices from "Donald Duck"
Multplied seconds with 23,97, then divided it with the
new framerate 25fps.

[Jooner]

Please CHECK before you start to do any frame-rate conversion.
Most modern DVD players do support PAL, NTSC and NTSC(film) format.

[bugster]

Please CHECK before you start to do any frame-rate conversion.
Most modern DVD players do support PAL, NTSC and NTSC(film) format.

Good advice, especialliy for Europeans where most modern TV's are multi-standard (Pal AND NTSC support) but AFAIK, most US TV's are NTSC only so for many of our American Cousins, PAL to NTSC conversion is necessary.

[cobra967]

It apper to me that this giude is to convert from NTSC to PAL. What about converting from PAL to NTSC? What selections/calculations do I need to make?

Thanks

[EddyH]

Not bad at all

another simplistic method, if you have the tools to do it and don't mind a couple of semitones up-pitch shift, to get from NTSC 48khz (DVD) to PAL 44.1khz (S/VCD) -

load up the 48000hz audio (cooledit, goldwave, whatever)
change playback rate to 30030hz (does not alter the actual file)
convert sample rate to 26460hz in best quality (may take a while...)
change playback rate to 44100hz
save

done!
The numbers may seem a bit odd, but they were arrived at after a bit of trial and error and a lot of maths (or t'other way round?). the best way to keep it very much in sync without using 'silly' very high or very low numbers that may make inconsistencies (unwanted high-pass filter, for one) or be incompatible with your audio editor. It's still not perfect, but I found that for a three hour film (258940.8 frames.. ) :

258940.8fr / 25fps = 172m 37.632s (37s 15.8f) = 10357.632

258940.8 fr --- 180'00"00 --- 518400000 samples at 48khz, 23.976fps
518400000 / 30030 = 17262.73726r
17262...*26460 = 456772027.9720r
456772028 samps / 44100hz = 10357.64s

10357.64s minus 10357.632s = 0.008s = 0.2 frames

So it doesn't keep *totally* in sync, but after three hours of film (which is the practical upper maximum for any xVCD) it's only one-fifth of a PAL frame askew, which NOBODY will be able to spot. The distance between you and the TV will create a bigger delay!

I think my program may have a slight bug, because occasionally there's a two or four frame desynch that happens, but that may be to do with the source file, and it's easily fixable by "centering" the soundfile so it slowly progresses e.g. from being 1/2 the amount early to 1/2 the amount late. it still takes about as much as 3 frames to make a really noticable desynch, especially for e.g. animated features which may only be running at 8fps anyway!
(it wouldn't help to reconvert to 26460 or 26459, as that small change creates an even bigger skew!)

[kryne]

hi i am trying to convert a movie, i got the video to convert fine but besweet dosnt seem to be working, i am using windows xp, it just sits there saying transcoding, never changes just wondering if anyone could help me out here

[stavr0]

I've found that AVISYNTH 2.5 does good framerate conversions.

In the case of (s)VCD PAL to NTSC telecine conversions, the original film are simply sped up to 25FPS, so instead of fooling around with 50-60 conversion and complicated pulldowns, just use the AVISYNTH command:

AssumeFPS(23.976,true)

This will slow down the frame rate back to NTSCfilm standard -- and takes care of the audio too (sync_audio=true). However, the resulting audio stream rate is a non-std 42294 or 46034 (44/48kHz)

TmpgENC happily accepted the AVISYNTH output. VERY slow (6h for 1.5h), but it worked. I decided to go straight to ATI TV-out and record to VHS, AVISYNTH was able to feed at 23.976 with no frame loss or audio glitch (1.4gHz AthlonXP), opening the .AVS in Media Player worked fine.

If your encoder does not accept non-std audio sample freq, you could throw in a resample upwards in the AVISYNTH script:

ResampleAudio(50050)
AssumeFPS(23.976,true)

Upsample then slow down to 48kHz

ResampleAudio(45984)
AssumeFPS(23.976,true)

Upsample then slow down to 44.1kHz

For the 60/50 conversions, the ugly legwork has been done:
SmoothDeintelacer scripts
Audio timeshift/resampling still needs to be done however ...

[Pratticus]

I tried using the built-in PAL->NTSC converters of BeSweet, it seemed to work, but the output had snapping every half second or so.

Any suggestions?

[classicjazz123123123]

ahhh
can some please help ! what is aviSynth, and how do i use it ? i am completely stuck on 1.b

JDJD

[classicjazz123123123]

and not only that but it says on 1 A

Set whatever you want else, select "video only" and start conversion

where is this option ??

any help of the 2 questions would be apprectiated

JDJD

[JazzMC]

www.avisynth.org

Read the FAQ and the manual to find out what it is

Jan .

[mjvgiese]

I'm having the same problem as classicjazz123123123, I'm stuck on 1a! I cannot find the "video only" option! Should I just not worry about it? Or should I just empty the "Audio Source" box and leave it blank?

HELP!

[oddbod77]

and not only that but it says on 1 A

Set whatever you want else, select "video only" and start conversion

where is this option ??

any help of the 2 questions would be apprectiated

JDJD

It's in the main window of TMPGENC on the lower right hand side just below "Stream type", if you cannot select any of the buttons (i.e. they are grey and don't do anything when you click on them) then click the "Load" button below and choose the "unlock.mcf" template.

@Mjvgiese: Clearing the "audio source" box is not enough, that will produce a video with silent audio which is not the same thing.

[Machine514]

Video is no problem, I am having a problem with the audio. It sounds like it is sped up (which it probably is). Is there any way to get it to sound like the original?

I am converting VCD PAL to VCD NTSC.

-Machine

[bugster]

Video is no problem, I am having a problem with the audio. It sounds like it is sped up (which it probably is). Is there any way to get it to sound like the original?

I am converting VCD PAL to VCD NTSC.

-Machine

Some audio editing apps can stretch/shrink the length of audio with little to no change to the overall pitch. I think Sonic Soundforge can do this, probably others.

[Machine514]

Thanks for the info. I will try it tonight and let you know!

-Machine

[Machine514]

It worked like a champ! I converted PAL VCD to NTSC VCD and burnt it to a VCD. I watched it on the computer and DVD player and worked fine. All audio and video was in sync.

I am trying a second one (an SVCD) and I will let all know how I did it.

-Machine

[DivXExpert]

With 15FPS you can use the ChangeFPS command and it will double every frame and double the frame rate, so you have 30fps, slow down with AssumeFPS(29.97), thats that. That can also be done with a framerate like 12.5 or 12. If your destination fps cannot be evenly devided by your source rate (not exact, but fairly close, 4% difference at the most), then you can use the ConvertFPS command.

[dg_phillips]

I discovered a much easier way to convert NTSC to PAL. I used Virtual Dub as a frameserver and TMPGEnc as client for the new encoding.

That's all

Warrior...I have tried this (Item 1C) in the Conversion Guide above and
it does not work for me. I must be missing something....hopefully you can tell me what I'm doing wrong. My steps are below:

Frameserv with VirtualDub

1. Start VirtualDub
2. Select File -> Open video file...
3. Select File -> File Information...
note the fps (25.000 PAL or 23.976/29.970 NTSC)
4. Select Video -> Frame Rate...
Select Change to [ 23.976 ] frames per second [NTSC] or
Select Change to [ 25.000 ] frames per second [PAL]
5. Select File -> Start frame server...
Frameserver Setup -> Start ->
Save .vdr signpost [specify filename] -> Save

Then I get a box that says Frameserver mode - VirtualDub
Frameserver name: Filename
Non-A/v requests: 0
Number of frames served: 0
Audio segments delivered: 0
Frameclients installed: AVIFile only

and nothing...it just seems to stop here. What am I forgetting?

[Machine514]

Check my guide...

https://www.videohelp.com/forum/viewtopic.php?t=166237

-Machine

[machine head]

Thank's Truman for showing how to do this, being a newbie at this game i'd come accross this problem quite early for which i was looking for the solution.
I've had success with all the files i've converted with this method, it was just what i had been looking for
I have discovered, quite by accident, however, that section 1 of the guide does'nt need to be carried out, just section 2 for which i used your besweet method. Just use the original AVI file with the new audio mp2 file when multiplexing, also checking the "do not frame rate conversion" box and this will keep everything in sync. I would imagine this would improve picture quality as the original file will only have been decoded once?

[TheDJ®]

why is the mp2 file being processed at 44.1khz? I'm just curious, coz dvd author only excepts 48khz??

Also it might be helpful if u add which options to select at 2a (SSRC & 2Lame).

[Gazorgan]

Because MP2 isnt' a standard for 23.97 NTSC video. Doesn't matter if it's 44 or 48, you can't make a complient NTSC DVD out of it. You can make a complient 44 Khz SVCD out of it.

[TheDJ®]

Ok cheers

[redkater]

I used the besweet option for the sound conversion and it worked fine, except that at the end the sound was cut off.
Exactly at 23.976/25th part of the movie the sound was gone.
I checked the wavefile and the soundlength that my winamp showed was 23.976/25th of the original filmlength.
Appending silence in Besweet didnot work.

Has somebody any suggestions?

John

[LuckyShot]

Finally found what seems to be the guide I been looking for, THIS guide!! But I have one When I decompres the wave in VdubMod, is it a "Direct stream copy" or in "Full prossing mode"! Think it must be "Full prossing mode", but I want to be sure. Tried to do the this conversion for nearly 2 week on and off!!! Getting to the point AGAIN where I just delete avi´s if they are 23,976!!

Thank for the guide!

[TheDJ®]

Finally found what seems to be the guide I been looking for, THIS guide!! But I have one When I decompres the wave in VdubMod, is it a "Direct stream copy" or in "Full prossing mode"! Think it must be "Full prossing mode", but I want to be sure. Tried to do the this conversion for nearly 2 week on and off!!! Getting to the point AGAIN where I just delete avi´s if they are 23,976!!

Thank for the guide!

Save .wav as DIRECT STREAM COPY, then use besweet to frameconvert it to MP2 file, frameconverting AC3 seems to cause alot of problems.

If you try using full processing mode, u will get an error most of time "Audio decompressor could not be found."