audio issue
by apxq12
on
May 31, 2007 at 1:14:18 pm
Here are the facts:
I've brought a 152MB MPEG movie that contains both audio and video into a new AE 7.0 comp. I've layered 2 small PNG files on top of it and want to render it out as a Quick Time.
Problems (in order of importance):
1. The audio stutters on playback. (Sometime it's barely
noticeable, other times it's more like a pause than a stutter)
2. I get better results using the render que than just exporting,
however when using the que, my 8 minute video takes 2.5 hours
to render, and my 152MB file jumps upto 3 GB.
3. I'm rendering at 1280 x 768. That's what it says in the comp
settings, and that's what it says it is in the QT video info.
However, my screen is that size, and I know that something is
off somewhere because the QT player doesn't fill the screen.
What I've tried and other info:
Exporting as MPEG, AVI, QT, (which is what I really want), and
even just the audio as a WAV.
I've tried every compressor listed, Sorenson, H.261, MPEG, etc...
The file plays back fine on it's own (pre-AE), and plays back
fine in program with a RAM preview.
The frame rates are the same - I've double checked.
I've tried rendering on 3 different PCs, so I don't think it's a
Hardware issue.
Any help would be appreciated! The audio issue is the main problem, but they all need to be fixed.
Thanks!
Re: audio issue by Dave LaRonde on May 31, 2007 at 1:40:34 pm
Here's the solution: convert all those mp3s you're using as audio sources to uncompressed formats like aiff or wav.
NEVER use mp3s in AE when you want to render out the audio. Not ever. They're the kiss of death. Sure, the Adobe propoganda lists mp3 as a supported file format, but they lie. So don't use 'em. I don't EVER use 'em, even if I have no plans to include audio with my animations... you never know, y'know?
Adobe SAYS they're going to solve the mp3 problem in AE8, but I'm not holding my breath....
Re: audio issue by Dave LaRonde on May 31, 2007 at 1:54:00 pm
I should read more closely. You're not using mp3s, you're using an mpeg with video and audio. That's just as bad as an mp3, and for the same reasons.
If you absolutely, positively MUST have the audio hooked to the video, you will need to export the source footage's audio as either an aiff or a wav, and then use that in AE.
But if you can add the audio to your rendered AE file later, cripes, just spare yourself the grief and do it then.
Re: audio issue by apxq12 on May 31, 2007 at 8:55:15 pm
I tried using the audio and video seperately, but it didn't work out. The audio problem still exists. Of course I have to use AE to render the audio out as a WAV because that's all that's available to me here at work. Do you know of another way to change the MPEG file and seperate out the audio? (That doesn't require buying another program?)
Thanks
Re: audio issue by Dave LaRonde on May 31, 2007 at 9:16:57 pm
[apxq12]"Of course I have to use AE to render the audio out as a WAV because that's all that's available to me here at work."
Well, that stinks, because you're using the application that's CAUSING the problem to try and FIX the problem. Good luck!
Do you HAVE to include the audio with the video?
"Do you know of another way to change the MPEG file and seperate out the audio? (That doesn't require buying another program?)"
I take it you're on a Windows box. I'd try downloading a freebie audio editor to do the job, because I don't think Windows Media player can do it. Well, maybe you have to download something from Microsoft to make windows media both read and write. I'm on a Mac, so I don't know for sure.
Re: audio issue by Dave LaRonde on May 31, 2007 at 9:33:15 pm
Here's a thought: what if you bring the original mpeg file into Sorenson Video, export JUST the audio as a wav file, then use the wav in AE?
I don't know if your problem is so much a audio sample rate mismatch as it is an audio compression problem. AE hates compressed audio, whether it comes in as the audio track of an mpeg or whether it's an mp3. Such audio sources cause AE to put annoying periodic clicks into the audio it renders.
Re: audio issue by Steve Roberts on May 31, 2007 at 1:52:32 pm
First, you need to commit to a specific codec and frame size for a specific purpose.
- Where is the rendered movie going? An editing app? A compressor for MPEG-2?
- What is the final playback medium? Web? DVD? Tape? Your hard drive? Somebody else's hard drive?
Please be specific.
1. If the audio stutters on playback, your data rate may be too high for the hard drive to play. Does it stutter in a RAM preview?
Also, AE doesn't like importing highly-compressed movies. Try using QT Player to convert the movie to Animation codec or Photo-JPEG Quicktime, then import into AE.
Why are you using 1280x768? That's very large. Please explain why you want to make a movie that size.
2. Only export when you have to. Otherwise, use the Queue. 2.5 hours may or may not be a big deal for an 8-minute video -- it depends on your effects. The file size is because you are making an 8-minute 1280x768 file, probably using a low-compression codec.
3. It sounds as if you just dropped the thing into AE. QT's size indication doesn't always help. Once again, you need to commit yourself to a specific size, purpose and codec for your video before we can help you,
Re: audio issue by apxq12 on May 31, 2007 at 9:03:51 pm
Okay, I'm committed to using Sorenson 3 and rendering as a QT movie. That's my goal and I'm sticking to it! ;p
The final product will be used on a HD touch-screen application. Just how the specific app works, I don't know...I'm just the graphics person. All I know is that I've been told to render the file as a QT and to make the size 1280 x 768. I'm new to the job and I do what I'm told.
The file does not stutter in a RAM preview, but I don't think that data rate is the issue since files that are much larger (bothe physically and file size)have played back fine.
Thanks.
Re: audio issue by moldyboot on May 31, 2007 at 1:53:36 pm
your audio issues may be due to an audio rate mismatch. the rendered audio rate needs to match the original audio rate. this audio was part of the movie, correct? it isn't an added mp3 (ae doesn't seem to work well with mp3s).
your file size will get very large if you render to a lossless (default) or uncompressed format. your final destination for the file will help decide what other codec you might want to choose. generally you waould like to render out losslessly, then compress as the final step, but that can be adjusted if you know what codec you will need int the end.
the render time seems long for just two overlayed images, so i think something else may be going on.
the frame size seems a bit odd 1280x720 would be a normal hd size. have you checked the frame size in ae... select the footage in the project window and next to the thumbnail at the top it should give your the size, duration and frame rate. again knowing your destination would help decide if you needed to make the file conform to normal hd.
Re: audio issue by apxq12 on May 31, 2007 at 9:09:28 pm
I agree that it sounds like an audio rate mismatch. (Yes, the audio was part of the original movie.) I see clearly that the frame rates are the same....how can I tell what the audio rate was/is?
My bosses would most like me to use Sorrenson 3 and render as a QT file for the sake of thier HD touch-screen app. That's also the reason for the frame size. It's specific for what this company does.
Re: audio issue by moldyboot on May 31, 2007 at 11:19:53 pm
qt 'get movie info' may give you the audio rate. but i think you may be best off separating the audio like dave suggested. especially since you're not seeing any other render issues.
