Audio not synching at 24fps

Jason_T · Post by **Jason_T** » Mon May 29, 2006 3:35 am

Hi all, new to this whole thing and the forums. Read the entire AbsoluteDestiny writeup and everything pretty much makes sense. I've gotta say though, this whole 24fps thing is working my nerves. I'm using Adobe Premiere 6.5 and I've got my video to 24fps, that wasn't a problem. Using BeSweet, I took my .ac3 file that i ripped from the dvd and made a .wav file from that. I'm assuming, from the guide, that this .wav file is 23.976 fps. So I used BeSweet again and used this new .wav file as the input and chose to convert it from .wav to .wav to 24fps. But when I take this (supposedly) 24fps .wav file and put it on the timeline in Premiere it's a good deal shorter than the video file and everything's out of synch. What am I doing wrong?

Willen · Post by **Willen** » Mon May 29, 2006 12:27 pm

It sounds like you have your steps in the wrong order or are following the wrong portion.

The very first thing when editing in 24fps for later conversion back to 23.976 (OPTION 2) is to change everything you are editing to 24fps. Use AssumeFPS(24) in your AviSynth scripts when making clips. Rip your music and load into BeSweet to make a 24fps version that is slightly faster and a bit shorter time-wise. Then load everything into Premiere and edit away. After you are done, then use AssumeFPS(23.976) on your exported video when converting to Xvid or MPEG. Reattach the original speed/length audio (not the 24fps one used for editing) to the file, preferably a MP3 compressed version.

It seems like you imported your clips, which I assume you converted to 24fps, edited the video, but used the original audio source to do it instead of the 24fps converted audio (OPTION 1).

Now, your options are this:
1) follow OPTION 2: re-edit the video with the correct 24fps audio and follow the steps for conversion back to 23.976fps later.
2) follow OPTION 1: export your video and audio separately. Change the 24fps video to 23.976fps with AVIfrate or AviSynth. Change the audio to match using BeSweet from 24fps to 23.976fps.
3) leave it as 24fps (non-NTSC standard), which isn't a problem for computer playback, but MPEG-2 convention submissions may be another issue.

Jason_T · Post by **Jason_T** » Mon May 29, 2006 6:06 pm

Thanks for the reply. I think I'm doing what you're saying though. I'll give a more detailed explanation of my steps. I haven't edited anything yet, I noticed this when I was prepping to edit my first clip in the montage. Just for reference, I'm ripping off of the StarWars special edition original trilogy widescreen. The steps I did were as follows: put my vobs in dgindex and got my .d2v file to put into virtualdubmod. Now, in the avisynth script in VDUBmod all I put was "AssumeFPS(24)" and "LanczosResize(848,480)". Made my low-quality .avi file and put it on the Premiere timeline. I double-checked with AVIfrate that the video was 24fps just in case Premiere was lying to me and indeed, it is. Now on to audio: am I correct in assuming that the untouched .ac3 file is 23.976 fps? I'm under the impression it is so I load BeSweet and use my .ac3 file to create what I'm thinking is a 23.976 .wav file. But I want 24 fps right, so I turn right around and take the 23.976 .wav file and turn it into a 24 fps .wav file, again with BeSweet, via the AbsoluteDestiny_WAV_23.976_to_24fps. Now I have my original titled .wav and another one titled "originaltitle.wavNEW". When I put EITHER of these .wav files on the timeline next to the video they are shorter than the .avi file in length and everything is out of synch. It DOES sound like the audio is moving along rather quick, could it be then that my video is still slower at 23.976 fps for some reason?

Jason_T · Post by **Jason_T** » Mon May 29, 2006 9:15 pm

I suppose I'll add that for this particular clip I am trying to synch the audio and video to the same chapter in the same DVD...so basically, I'm just looking for an editable copy of this DVD chapter.

Jason_T · Post by **Jason_T** » Mon May 29, 2006 10:44 pm

I think I may have royally misinterpreted the guide. I thought Premiere could only edit 24fps video and audio....this isn't the case, is it?? My footage will always be 16:9 29.97fps NTSC footage from these dvds, and I can leave it at that, correct?

gangstaj8 · Post by **gangstaj8** » Tue May 30, 2006 1:06 am

Jason_T wrote:I think I may have royally misinterpreted the guide. I thought Premiere could only edit 24fps video and audio....this isn't the case, is it?? My footage will always be 16:9 29.97fps NTSC footage from these dvds, and I can leave it at that, correct?

That's correct, Premiere can use more than just 24fps, EADFAG recommends against using 23.98fps footage, that's all. You can keep your footage in it's original frame rate and it should sync up just fine.

Qyot27 · Post by **Qyot27** » Tue May 30, 2006 7:03 am

Jason_T wrote:I think I may have royally misinterpreted the guide. I thought Premiere could only edit 24fps video and audio....this isn't the case, is it?? My footage will always be 16:9 29.97fps NTSC footage from these dvds, and I can leave it at that, correct?

That was probably the problem, actually. The audio was lining up with the 24fps markers, but if you didn't do inverse telecining on the video, then you were just telling 29.97fps video to play back at 24fps, which will make it longer because it's slowing the video down. The problem was with the video itself, not the audio.

If you used DGIndex's Force Film feature, or if you included Telecide/Decimate or TFM/TDecimate, etc. in the file and then AssumeFPS(24), it should have lined up perfectly.

If you want to use 29.97fps audio, you don't do any adjustments of the audio, except decoding to wav.

Qyot27 · Post by **Qyot27** » Tue May 30, 2006 7:03 am

Qyot27 wrote:If you want to use 29.97fps video, you don't do any adjustments of the audio, except decoding to wav.

Gah, this is what I get when I don't get any sleep.

gangstaj8 · Post by **gangstaj8** » Tue May 30, 2006 7:14 am

Qyot27 wrote:Gah, this is what I get when I don't get any sleep.

Hey, that's no excuse, *notes current time* especially in this community...

Jason_T · Post by **Jason_T** » Tue May 30, 2006 12:28 pm

Excelleeenntt...thank you much people!! I hear you about no sleep, I was so excited to get stuff synched last night that I didn't stop until I got my intro done! w00t! well...except for a quote and title I want to include. Hey, any of you know a good effects program that I can use to add text and maybe some visual effects to my video? If it's included somewhere in Premiere or the AMVapp then I've got it and it just takes finding...if not, I really only wanna go shareware 'cause I'm broke! Thanks again-