AVI2SVCD audio speed

[loco-remate]

Hello everyone.

I have a problem creating a SVCD file with DVD2SVCD. I load the original avi file which has a 29.970 fps and I select to convert NTCS to PAL.

The problem is that when i play the converted (SVCD) file the audio is like 2 times slower than it should, although it is perfectly synchronized with the video.

I tried playing the file with BSplayer and only after adding a 20% in playback rate I was able to get the right speed for the video/audio.

What should I do to fix this problem? :scared:

All comments appreciated
:sly:

[Nick]

Hi there, welcome to the forums!

Firstly - Problem post - moved to Basic.

With regards to your problem, NTSC AVI files can have 2 framerates - 23.976 or 29.97.

PAL files are always 25fps.

All NTSC2PAL does is convert the framerate. To do this it speeds up 23.976 files by about 5%, which is barely noticeable, but has to slow down 29.97 files by nearer 20%, which is dreadfully noticeable.

I never convert NTSC2PAL. Although I live in a PAL country (UK), most DVD players here will quite happily play NTSC SVCD's and DVD's.

If you really have to do this, depending on your source file , it may be possible to convert it to 23.976 fps. Film source is 24fps. To get film source up to 29.97fps for NTSC TV's without radically speeding the film up, it is firstly slowed down very slightly to 23.976fps. Then every few frames an extra frames are generated using fields from surrounding frames. If this has been done on your source, it can be reversed. If this is not the case, however, removing frames will inveviatbly introduce jerkiness.

However, being from a PAL country I've never had to do this. Perhaps someone from NTSC-land will come to your aid on this point.

Cheers
Nick

[jsoto]

Sorry...
Seems this thread has been "cloned" (not moved) and I replied in the wrong one..

This is my reply

Hi,
As Nick, I'm a PAL user and do not have much experience on this, but AFAIK there are two ways to do a frame rate conversion

a) "Assuming" a new frame rate. Audio should be pitch corrected to be in synch. Total movie duration changes.

b) "Convert" the frame rate. Audio is not corrected and movie duration is the same. This method is very much CPU consuming, and there are some issues (and tricks) with interlaced material. I used this method only once but with very good results (mainly because audio was the important thing: it was an old jazz concert).

jsoto

[Nick]

Sorry
My mistake, thanks for bringing it to my attention.
Thread in Advanced now removed.
I'll strike myself for cross posting :D

[loco-remate]

Thanks guys for your replies.

I'm making the SVCD for a friend of mine, and it seems his DVD player can only play movies in PAL format. So I guess that in tis case I'll have to use Nick's method.

:)