Conversion of a 29.97 fps avi to 25 fps pal vcd

[Swin]

Hi,

I fairly new at this so forgive me if I've posted in the wrong group.

I have been converting some AVI files with a frame rate of 29.97 fps to MPG format with a frame rate of 25 fps suitable for a PAL VCD.

I have used a very simple one line command (ConverFPS(25)) in the Avisynth script when running DVD2SCVD to achive this so far but have come across many posts by Xesdeeni with slightly more complicated scripts to achive the same effect. I basically wondered what this kind of script would do and would there be any advantage in using it for this particular type of conversion.

This script was developed by Xesdeeni and easy2Bcheesy here (http://forum.doom9.org/showthread.php?s=&threadid=45459&perpage=20&highlight=ConvertFPS&pagenumber=2)

The final AVI Synth script I used for NTSC to PAL is...


# NTSC (29.97fps) to PAL (25fps)
LoadPlugin("SmoothDeinterlacer.dll")
AVISource("NTSC-Source.avi") # Change to your filename
SeparateFields()
Weave()
SmoothDeinterlace(doublerate=true,lacethresh=1,staticthresh=20)
LanczosResize(720,576)
ChangeFPS(50)
SeparateFields()
SelectEvery(4,1,2) # Change to SelectEvery(4,0,3) if output video looks very jerky
Weave()
ConvertToRGB() # Might not be essential



Stunning NTSC-PAL conversion using VirtualDub!! Seriously guys, the quality has to be seen to be believed.



Many thanks

Swin

[Awatef]

I havn't tried the script above, but it doesn't seem revolutionary to me, it sounds like someone asks you for your right ear and you show to it with your left hand... and I doubt it delivers very good results
For example, what the **** is the meaning of separatefields directly followed by weave, this doesn't make any sense.
Second, why would one delibrately deinterlace before the decimation
etc

anyway, if you got a 29,97fps avi with duplicate frames into it (every 5th frame is a dup of the 4th one), go this way:

loadplugin("...\decomb.dll")
decimate()
assumefps(25)

and accelerate your audio properly (23.976 -> 25)

Else, I suggest this:

loadplugin("...\decomb.dll")
separatefields()
selectevery(12,0,1,2,3,4,5,6,7,8,11)
weave()
FieldDeinterlace()
assumefps(25)

and accelerate audio properly (24.975 -> 25)

[Swin]

It doesn't look that way. Just clicking through the frames in VirtualDub or whatever shows each to be separate and distinct in the source AVI.

I would assume that just dropping frames would lead to a somewhat jerky video. I did try the ChnageFPS command and that exactly what happened here. Also I believe the scripts do not alter the final length of the movie so that no audio conversion should need to be completed. At least with the simple ConvertFPS that what’s seems to happen. I have a feeling that the script above is intended to be used on interlaced sources but I'm not entirely sure.

As said I'm, VERY new at this. I'm guessing that the AVI files I have are progressive - or at least converted to look like that - need to do a bit of homework on this subject.

Swin

[Awatef]

it works for interlaced and progressive, no big difference.
ConvertFPS does indeed a good job when it comes to 29.97 -> 25
I just suggested the selectevery method for you to compare and see what suits you best.

If you ever get a 29.97 source with dup frames, be sure to use the decimate method though, to get perfect results.