About to give up on 24000->23976

Corran · Post by **Corran** » Sun Jun 06, 2004 12:32 pm

That difference in length will hardly be noticable, if at all. It is more of a quality freak issue than anything. I'm not sure what the problem is but if you continue to have problems you can always use the 24fps audio.

Unfound · Post by **Unfound** » Sun Jun 06, 2004 12:37 pm

Corran Productions wrote:That difference in length will hardly be noticable, if at all. It is more of a quality freak issue than anything. I'm not sure what the problem is but if you continue to have problems you can always use the 24fps audio.

Actually, the difference in length is what's causing it to be off sync. (And, personally, I like Korn at 23.976 seeing as they're supposed to be deep)

Corran · Post by **Corran** » Sun Jun 06, 2004 12:58 pm

You can honestly notice a .1% difference in pitch? No one has ever said anything to me about my Shinobu video. I got lazy on when exporting and decided to export directly from premiere at 24fps and leave it that way.. There are a lot of editors that choose not to make this change. The only real reason people need to concern themselves with it is when submitting to a con as 23.976 is a standard video frame rate. For online distro 24fps is perfectly fine.

Unfound · Post by **Unfound** » Sun Jun 06, 2004 2:09 pm

I'd just like to figure out what's wrong so I can fix it for next time.

Scintilla · Post by **Scintilla** » Sun Jun 06, 2004 2:21 pm

I think I tried using the ABCavi tag editor once and having it not work quite right. After that, I just kept my export at 24 and used AssumeFPS(23.976) in AVISynth. See if that works any better.

Only other thing I can think of is that perhaps the audio didn't get sped up properly when you made the 24fps version.

Unfound · Post by **Unfound** » Sun Jun 06, 2004 3:05 pm

Alright, I FINALLY figured it out. The original audio, for whatever reason, was in 23 fps (Why, I have no idea) and not in 23.976 because when I put the fps at that for the video, its on sync and the audio+video are the same length. Go figure. So, I'll either have to change the audio from 23->23.976 (Which I'm trying now) or just make the video's FPS 23. (This would also explain why I could tell the difference between the two tracks so easily when editing in Premiere.)

Unfound · Post by **Unfound** » Sun Jun 06, 2004 3:35 pm

Alright, that didn't work. Apparently, I can't convert audio into 23.976 successfully, however, the video will convert to 23.976 just perfect. I honestly have no idea why it does this.

AbsoluteDestiny · Post by **AbsoluteDestiny** » Sun Jun 06, 2004 5:12 pm

Well - when I have problems like this, here's what I do.

1) Go into virtualdub and find out the exact length of the video stream

2) Get the highest quality wav copy of the audio around

3) Put the wav into a real wav editing program like soundforge or cooledit or maybe even audacity

4) Use a time stretch tool (one that doesn't change pitch) to get the audio length to fit the video length exactly. In sound forge does this pretty well.

Export the newly sampled audio and put it on your video.

Scintilla · Post by **Scintilla** » Sun Jun 06, 2004 5:39 pm

Unfound wrote:Alright, I FINALLY figured it out. The original audio, for whatever reason, was in 23 fps (Why, I have no idea) and not in 23.976 because when I put the fps at that for the video, its on sync and the audio+video are the same length. Go figure.

I thought I should point out that audio doesn't come in frames per second. We say "convert audio from 23.976 to 24", but all that really means is that we're making it (approximately) 0.1% faster. You could just as well say "convert audio from 29.97 to 30".

So if the original audio syncs to the video when you force the video to play at 23 fps, all that means is that you messed up somehow in the beginning and made the "24 fps" version of the audio too fast. I'm actually guilty of this very error in "Haruko the Superfreak"; I converted my audio in SoundForge XP instead of BeSweet, and I made the mistake of converting it to 44541 Hz (a full percent faster) instead of 44144.1 Hz. Stupid me.

Unfound · Post by **Unfound** » Sun Jun 06, 2004 6:37 pm

Scintilla wrote:
Unfound wrote:Alright, I FINALLY figured it out. The original audio, for whatever reason, was in 23 fps (Why, I have no idea) and not in 23.976 because when I put the fps at that for the video, its on sync and the audio+video are the same length. Go figure.
I thought I should point out that audio doesn't come in frames per second. We say "convert audio from 23.976 to 24", but all that really means is that we're making it (approximately) 0.1% faster. You could just as well say "convert audio from 29.97 to 30".

So if the original audio syncs to the video when you force the video to play at 23 fps, all that means is that you messed up somehow in the beginning and made the "24 fps" version of the audio too fast. I'm actually guilty of this very error in "Haruko the Superfreak"; I converted my audio in SoundForge XP instead of BeSweet, and I made the mistake of converting it to 44541 Hz (a full percent faster) instead of 44144.1 Hz. Stupid me.

Well, I even tried to re-do the BesweetGUI part, but it came out the same length at 24 FPS again. Although, I just did the calculation and .99% of 2:46 (The original audio length) is 2:4354 and has a higher pitch then it is apparently supposed to have (Judging by the replies in this topic). I probably did make a mistake in BeSweetGUI, so I'll have to revive the other topic in audio help to figure out what I did wrong.