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JButts
17th July 2005, 07:07
I used AVIsynth to import .avi files into encore that weren't the right dimensions (the proper name escapes me right now!), and successfully linked all the files to their respective buttons on the menu. In the Preview window everything is perfect but once it's actually been burned the audio does not sync up with the video. Anyone have a solution to this problem, please?

mg262
17th July 2005, 09:23
If you aren't using trim anywhere, just resizing, this is IMO probably not an AVISynth error. Where are the avi files from? If it's from a capture card, you might find that their underlying frame rate is slightly different from what it should be (e.g. 24.986 rather than 25) and the encoder assumes that it is an exact number (e.g. 25), speeding up/slowing down the video slightly and causing a loss of audio/video synchronisation.

JButts
17th July 2005, 17:42
The files themselves are not from a capture card, they're just a couple fanfilms that I liked and wanted to put on to a dvd. Is this problem something to do with Encore itself then?

LocalH
17th July 2005, 18:20
Still, I would recommend checking the frame rate. If you're using NTSC, then the film frate rate is 23.976fps (accounting for the same 1000/1001 factor that makes regular NTSC 29.97fps instead of 30fps), which can be done to a 24fps video by doing something like this in Avisynth:
AssumeFPS(24000,1001,true)
ResampleAudio(48000)
and then encoding the result as NTSC film, so that the stream will contain the correct tff/rff flags to produce a 29.97fps output.

If you're using PAL, then the usual procedure is to speed up the film by 4% to 25fps, which can be done with something like this code, without changing the pitch of the audio (you don't have to correct for pitch in the NTSC case because the difference is so small):
AssumeFPS(25,false)
TimeStretch(tempo = (100.0*25.0)/23.976)
ResampleAudio(48000)
Depending on your target standard, one of these scripts should produce the results you want without dropping any frames (you'll lose a tiny bit of audio quality, but I doubt you'll notice it on playback).

JButts
19th July 2005, 22:11
Hey, thanks for the reply, but I'm kinda new to this so I'd appreciate your help.
Am I supposed to enter that code into the the .avs file I used to import the .avi file into Encore, or am I just supposed to make a new one?

Thanks again,

JButts

LocalH
19th July 2005, 22:40
You can put them at the end of the script you're already using, since you're probably at least resizing - adjusting the frame rate does not inherently affect the frame size whatsoever in Avisynth. Since you said you're using Encore, it sounds to me like you're encoding each AVI as a separate title, in which case you're probably using one script per AVI. In that case, you'll need to add that to each script (assuming it's not already at the exact frame rate needed, if it's 23.976fps for NTSC or 25fps for PAL then you're probably fine). You never stated whether you're creating a PAL or NTSC DVD, and that piece of information will help determine exactly what you need to do, and which piece of script you'll need.

JButts
20th July 2005, 00:15
NTSC, and thanks a bunch. I'll give it a shot tonight.

JButts