Ac3 Audio problems

Hello all.. As we are all aware camcorders that record in Mpeg2 format using Ac3 Audio cannot be imported into PPCS4.. I know this subject has been covered but i need an answer to this simple question...
Premier Elements 7 is a slim down version off PPCS4, PE7 costing like 90% less than PPCS4 (£70 Vs £700) So how is it that my BUDGET version (PE7) can import my mpeg2 files with ac3 audio at ease but my expensive version (ppcs4) cannot...? Adobe am i missing something here, I mean if it was the other way around then i could understand but I'm at a total loss here as to why my £70 package works better than my £700 package.
Is there Any files i can copy from PE7 to PPCS4 that will solve this problem...?
Many thanks.... Levi

Levi Ferdinand sez ---> Do you run the Video and audio as separate files within PPCS4
Yes, the video and the audio are two seperate files, and when the AC-3 is DD 5.1, then six mono tracks.
The only instance where I have to edit MPEG-2 video is when a DVD-VIDEO has to be re-authored and where the original source footage is not available.
In case you have one of this cameras which records to miniDVD, you can demulltiplex the camera miniDVD to MPEG-2 video and AC-3 audio, then transcode the AC-3 to WAV 48Khz and import the WAV into the video editor. The demultiplexing software (e.g. SmartRipper.exe) analyses the container format for offset between video and audio.
Typically the offset is 0 millisecond (no offset) to 80 ms; one PAL frame at 25 FPS is exactly 40 ms (1000ms:25f = 40ms/frame), so if the offset is for example 80 ms, then you displace the video against the audio by two frame on the timeline before you start editing. The MPEG-2 video itself gets transcode to HUFFYUVv2.1.1, this in order to cut the footage frame accurate and to obtained the picture quality until the video is re-encoded to MPEG-2 again as well to have transparency available. That's the professional way of re-authoring DVD-VIDEO, or how to edit MPEG-2 with Dolby Digital AC-3 in general.
Of course I don't know if that all helps, or if your workflow is completly different.

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AC3 Audio and Quicktime 7.6 Problem

I was wondering if anyone else is having a problem with opening an audio file with the .ac3 extension in the updated Quicktime 7.6?
What I have been doing, for a couple of years now, is that I capture a TV program from my DVR using the firewire port. Once the file is loaded on my Mac, I then open MPEG Streamclip, trim out the commercials, Export to Quicktime using H264 and 2 channel AAC audio, after the export is done, I would then do a Demux to AC3 to get a separate audio only file containing the 5.1 surround sound.
I would open the .ac3 audio only file, open the .mov video file (both in Quicktime). I would then copy the 5.1 audio track from the .ac3 file, Go to the .mov file, perform Edit/Add to Movie. This way I would have 2 audio tracks, AAC a 2 channel track and AC3 a 6 channel track.
But now with Quicktime 7.6, I cannot open the .ac3 file at all, I get "The file is not a movie file." error message with no error code.
Any suggestions?
Thanks,
Bill

POSSIBLE SOLUTION
I think I have discovered a way to workaround the AC3 5.1 sound problem.
I found an old 20GB drive and installed Tiger 10.4 onto the drive. I then downloaded the "MacOSXUpdCombo10.4.11PPC.dmg" file and updated the system to Tiger 10.4.11. I performed all of the updates (System Security updates and the Java updates) through Software Update except for iTunes and QuickTime.
I then downloaded the "QuickTime755_Tiger.dmg" file from Apple and updated to QuickTime 7.5.5
DO NOT UPGRADE TO 7.6
I then opened the TV show in QuickTime 7.5.5, I extracted the audio file from the program and saved as a separate audio file (it saves as a .mov file).
I opened this audio file in QuickTime 7.5.5 and then exported the audio
selecting Export Movie to QuickTime movie,
clicked on the options button,
the sound box should already be checked,
clicked on the settings button,
under the Format drop down I clicked on AAC,
Channels: I clicked on 5.1,
then Rate:48.000,
checked on Show Advanced Settings,
Quality: Normal,
Encoding Strategy: Constant Bit Rate,
Target Bit Rate: 384
(used MediaInfo Mac to gate this information),
clicked OK,
Clicked OK,
then named the file, saved it and then waited for audio to be converted from AC3 5.1 to ACC 5.1.
If you now open up this file in QuickTime 7.5.5 it is an ACC format with 5.1 and plays fine.
I then restarted to my regular drive with QuickTime 7.6 loaded and it plays the audio file without any problems.
I'm sure that there must be a way to repackage the AC3 audio file in an AAC container that will work better and faster, but for now this seems to work, so I am going to try some other shows that I have.
Let me know if this works for others.
Bill
Message was edited by: Boliver
Message was edited by: Boliver

Sync AC3 Audio to Video function problem

Hi there,
I have an AC3 audio track with embedded time code and a video mpeg-2 segment with embedded timecode that I want to sync together. I use DVD Studio Pro 4.0.3.
In the help file it tells me to drag the audio from the Asset tab to the track editor while holding down the OPTION key.
But, when I do this, the track doesn't synch automatically and I have to do it manually anyway. Any thought on why it won't work ? It works on the Scenarist stations we have here and the tracks are made on profesionnal-grade encoders.
Audio track (AC3)
start time: 09:59:55:00
end time: 10:59:36:12
Video track (Mpeg-2)
Start Time Code:09:59:59:00
End Time Code: 10:02:41:07
I have searched the forums and support pages without finding any hints. Your help would be very appreciated. Thanks !
Arnaud
4 x 2.5 Ghz PowerPC G5 Mac OS X (10.4.8)

Thank you Colin. Yes indeed, I have read that part in the help file, but it just didn't make any sense to me at the time.
After running some test to figure it out, I found out that DVD Studio Pro will only sync my audio when the audio starting Time Code is later than the Video starting Time Code.
So in other words, DVDSP only adjust audio start time automatically but does trim the audio automatically, which is just a partial sync function according to me.
I sincerely hope that the development team will add this functionnality in a near future. As it is right now, the DVDSP auto-sync function is almost useless for us here. Moreover, the ability to sync AC3 audio to multiple video segment in the same track would be a great plus. I don't think it would be that hard to implement, but who knows ?
Well at least we can do it manually ! Thanks again Colin !

Update 4.1. and AC3 audio

Alas no AC3 audio, anyone else experiencing this?

Bogus! I think that a lot of folk were. I could have sworn that I saw something about it being part of 4.1 - probably just one of those rumors...
Thanks for reporting, even if it's bad news,
Hunt
[Edit] I'm probaby thinking back to an issue with the SurCode DD 5.1 SS plug-in. I know that efforts to fix those issues were underway. That is obviously a problem affecting things in one way ->, but I'd hoped to see things fixed in the other way <-. Hm-m, OK, so it ain't perfect.

Dolby AC3 Audio (code "8192") format

I tried to find in the QuickTime forum about this topic but no success.
I received this message trying to watch a movie:
This file contains a track in the Dolby AC3 Audio (code "8192") format. You may need to install a DirectShow decoder for this audio format in order to hear the soundtrack of this file.
The problem is that I visit about 15 discussions webpages about this "AC3 Audio (code "8192")" and what I really got? Nothing that really worked. What I found was for PCs, codec in .exe and so on, but for the Mac, zero. I even bought DivX for Mac and it was a deception. I looked at Apple/QuickTime/Components and I was again at DivX page...
Any help would be great. Thanks in advance!
Mario Lordeiro, Rio de Janeiro

http://perian.org/
http://discussions.apple.com/thread.jspa?messageID=10368675

AC3 audio not compressing properly

I am compressing under the DVD selection. Everything was working great, until today. The compressor audio output for the AC3 audio has changed (different icon like a itunes file) and the DVD shuts down when I try to import the asset.
I cannot preview the audio. I went back and looked at earlier projects and I could always preview the audio in Finder. Any suggestion? I need to deliver the DVD on this project in 4 days. Help!
Thanks!

Presuming you are making an SD DVD you will most likely need to lower your video data rate.
If compressor is giving you problems this could be done in DSP.
Preferences/Encode/ If your show is under 70 minutes I would do average 6.5/max 7.7 and motion est. -best / background encoding. If your source is longer duplicate compressor data rates based on length settings. Drag your source movie from FC into assets.
This will create a MPG folder where your project is. Create an AC3 from the aiff and see how that works. Mac DVD player app is a good way to check and see how your burned disc will look. Build/check/burn from DSP or Toast.

Adobe CS6 audio problem

Hey guys, I'm really new to Adobe, I've been using SonyVegas for a long time now. I thought I'd try out a different program. I really like CS6's interface, it feels really natural. However, I can't use it for what I want to do. I record game footage from my Hauppauge HDPVR and commentate games on Youtube. Whether I save the recording as an .MP4 or .MT2S when I open up a new project in Adobe and import the video it will not drag the audio in with it. It works fine in Vegas, and when I watch the video the sound plays along just fine.
This may be a really no-brainer kind of problem, but I've never had an issue importing anything into Vegas, it just simply knows the video is coupled with audio. Adobe seems to only see there is a video.
If computer specs help rule out hardware incompatibilty I'm using two GTX 670's SLI. 3rd gen i7 processor, and 16gb of ddr3 2333 ram.

Something is going on here because cs6 supports AC3 audio. Can you upload a small test file to yousendit or some other share site, so I can see if it has audio on my system.
I'm thinking something might have gone wrong with your install process. Although please try doing this although this is supposed to only apply to AVCHD media it can't hurt to try.
This solution was originally posted in another thread by a adobe employee, and even though he was talking about AVCHD media it's worth a shot IMO.
1) Quit Premiere. Launch Premiere again. Go to the Help menu and verify that you are activated (towards bottom, should see "Deactivate..." that signifies that you are activated).
2) Go to Preferences > Media > Media Cache Database. Click the "Clean" button. Import your file(s) again and see if you get audio now.
3) If 1 and 2 do not work, then could you please try to uninstall and then install Premiere Pro again.

?Compressor 2 = 3.95gb-mpeg2 & 172.39 AC3 Audio ='s 4.6gb in "Disc Meter"??

Movie time = 2hours and 6 mins:
??? Compressor 2 = 3.95gb-mpeg2 & 172.39 AC3 Audio ='s 4.6gb in "Disc Meter" ???.
I just put these assets into DVDSP4 from FCP5 after using compressor 2 (Average bit rate = 4.5mbps, Maximum Bit rate = 7.5mbps, motion estimation = best, sound is sample rate = 48kHz, Data Rate = 192 kbps.
I looked in the forum but ditn't get an answer that solved this problem including reboot program change preferences ect...
I would grateful for a solution to this problem as I am new to dvdsp4 and my clients are waiting. Thank you for taking time to read this.
G5 1.8 ghz 512 ram Mac OS X (10.4.8)
g5 Mac OS X (10.4.8)

This issue comes up all the time
The meter is not always 100% accurate and the sizes being reported change depending on how you look at them - when you are looking at the size of the files, how are you doing that In Finder->Get Info? Which number the smaller or larger if doing it that way? The sizes can be reported different ways, take a look at the link above. Also try deleting the PAR/MPEG files and closing and reopening.
What size is the folder when it is built to the hard drive? Keep in mind there is some overhead from making a DVD
Also 2 hours 6 minutes (missed that in the original post, sorry) is very close to the edge on being able to fit on a DVD-5 with the rates you have - an average of 4.6 should fit in theory, but it is never an exact science

Exporting files with AC3 audio

Forgive me if this is not the right place to post this question.
Using QT Pro, I want to trim and edit some files containing AC3 (Dolby Digital) audio. When I export or save the edited video, will they retain the AC3 audio?
More specifics: These files contain both AAC audio (in the default track) and AC3 audio (second track). These files were encoded using Handbrake, and I will be playing them on my AppleTV (hence the desire to retain the AC3 audio). The source files come from my DVR, and I want to trim some commercials. I tried to trim them prior to encoding, but I'm having trouble finding reliable software for editing MPEG2 streams on a Mac. Thus, I'm trying to figure out whether or not I can trim them afterwards using QT Pro and still retain the AC3 audio.
Any thoughts would be appreciated. Thanks!

Aaah, I wish I could help! I have exactly the same problem! I was going to post about it, but since there's this workaround, I didn't want to take up bandwidth with a problem that was not a total showstopper.
Indeed. I have stopped doing what I used to do before. Before, I used to select "All" in compressor - the files generated were the video, the aiff, and the ac3. Well after burning a few coasters through DVDSP 4.1 where there was picture but no sound, I realized that I needed to drag the aiff file to compressor again, and use that - at that point everything is fine. So, right now, my workflow is to export just the video from FCP through compressor, let it encode. Then export the aiff separately and encode it to a3 in compressor, then import the video and ac3 to DVDSP for good results. In short, no more exporting "All" from FCP through compressor, it's a waste of time.
But as to why, I have no idea, and I'm eager to hear what folks have to say! Anyhow, just letting you know you are not alone. Btw. my set up is: FCP 4.5 HD, compressor 2.1 and DVDSP 4.1.0... what's yours?

How do I get AC3 audio on my DVD

Hi,
Thank you for reading and offering your help.
I want to make some DVDs using iDVD09. I have no problem creating and editing videos and burning DVDs using iDVD.
Here is my problem. I want to create DVDs that will be duplicated by a company that says no Mpeg audio. They want AC3 audio.
Could someone please help me out here. What do I do, so that I can create a video, use iDVD09 and have AC3 audio? Or if that can't be done, please tell me my options.
Thank you very much.

I don't have first hand knowledge of iDVD on this, but here's a post that suggests iDVD won't be able to solve your dilemma (unless the production house accepts PCM audio -- check this):
http://www.mhvt.net/quicktime/eng/idvd.php
DVD Studio Pro offers a greater range of audio encoding options, including AC3. You may wish to check Toast and other software, but if you like nice menus, you may be looking at Apple's Pro$$ software.
John

AC3 Audio - Is there a bitrate limit?

I've got quite a few HD movies that I've converted to MOV format using Visual Hub for use on my Apple TV. They all have AC3 audio. All but 3 of them play just fine. The 3 in question have flawless video (no skipping or stuttering) but the audio either stutters and cuts out or I just get popping noises. I couldn't see any difference in the files until I downloaded a program call MediaInfo Mac. It gives a ton of info about audio/video files. What I discovered is that although the sampling rate on the audio is 48.000 KHz the bitrate of the 3 in question is greater than 448 Kbps. The Apple TV specs don't indicate any limitation on bitrate for AC3 audio so I'm not sure if this is really the problem but so far it seems to be the only thing different about these files. It's my understanding that the Apple TV just does a pass-through of the AC3 audio to my A/V receiver .... could it be my receiver that's the problem?
Oh... the 3 problem files all play just fine in Quicktime/iTunes on my Mac.

I'm not too knowledgeable when it comes to audio, but yes I believe AC3 is simply passed through the tv, but I believe the problem that you have is that the DVD standard is 448 kbps, it sounds though something along the way, either your tv or your receiver is struggling with these higher datarates.
How are you playing AC3 from your mac with quicktime, do you have the ability to output this to your receiver so that you can eliminate it or confirm it as the problem.

Audio problems on Satellite L755-S5277

Since I bought this laptop two weeks ago, I've noticed intermittent buzzing sounds when playing back video. The sound emitted can best be described as a "digitized" sound that lasts for about a half-second and no other audio can be heard over the top of it. I've not noticed this when playing back pure audio MP3s, but I can reproduce this when playing back YouTube videos in Firefox or playing back MP4s and Divx videos (with AC3 audio) using VLC or Windows Media Player.
I've updated the audio and video drivers, as well as the Synaptics pointing device driver (thinking that there might be a conflict). I noticed that others have had this same issue and made posts to this forum.
Are there any solutions that have been found, or is the device defective and should be returned?
Thank you.
Tim

Did this problem occur immediately after purchasing, or did you install any software first?
- Peter

MPEG videos with AC3 audio in iMovie

Hi there,
Aplle seems to totally ignore AC3 audio streams (at least in MPEG videos)! Why?
My JVC cam corder records *.MOD files on its hard disc. Those files
are in fact MPEG2 files, but with AC3 audio.
Renaming the files makes them playable using the Quicktime Player, but
without the sound
MPlayer is able to play them correctly, but that does not help me,
because I want to use the videos in iMovie and iDVD.
I tried installing the 'AC3 Codec.component' (what is supposed to fix
the problem for AVI files)
and now I installed Perian, which does not do the trick either.
I can ofcourse use ffmpeg to convert the files, but that means a
quality loss and a lot of work I wanted to save by buying a Harddisk
camcorder, so I could skip the time consuming conversion from DV tapes
to mpeg.
I there anybody out there with a solution?

QuickTime doesn't like to play the multiplexed sound on mpg videos. The QT Plugin ONLY supports video playback and NOT the audio track of such content (as you have found out).
I suggest you look at VisualHub software ( http://www.techspansion.com/ ) to convert your files to DV. It works with my problem mpg-4 files with multiplex audio. It runs in a free trial mode so you can verify it does what you want before buying it.
F Shippey

Audio Problem since upgrading to Mountain Lion

Has anyone encountered audio problems with their iMac? I just upgraded to Mountain Lion on my i7 27" with 16GB of Ram and found that the Audio starts to get distorted and eventually cuts out after about an hour! It starts cutting in and out when I move the mouse and eventually there will be no sound at all!
Sometimes it can take over an hour of steady use, my last time was watching a movie on Netflix. I initially noticed this using a USB DAC Headphone Amp.
I never had any Audio problems before, my machine is over 1 year old.
I enjoy watching movies in iTunes and DVDs, but this is making it difficult! A full restart usually fixes the problem for a time but it will eventually come back
I'm seriously thinking of going back to Lion for the time being and seeing if it is a Hardware problem.

i don't know if mine is the same issue, but i had no sound through any of my applications after upgrading to mountain lion. here is what i had to do to fix it:
-- applications > utilities > audio midi setup > UNmute all options under "built-in output" (they were mysteriously muted)
Also, I noticed that the options for "use this device for sound output" and "play alerts & sound effects through this device" were no longer assigned to my Built-in Output device. They were assigned to some other random sound driver. To fix, i right-clicked on Built-in Output and reassigned those items to my built in speakers. All fixed now!
very weird problem, though.

Can Apple fix the 12 bit audio problem once and for all?

I have had persistent audio problems from I Life V3 all the way up to I Life 06. Sometimes it is synch issues. Sometimes it is audio dropping out. I have been through the various forums and applied the various remedies with some successs, some failure. The basic problem is that I have an extensive quantity of Mini DV tapes dating back to 1997, most recorded with 12 bit sound (prior to 2002). Apple's basic stance has been, you must use 16 bit sound or I Movie and/or I DVD won't work and . And proposes awkward workarounds. Basically placing the onus on it's own consumers. Why can't 12 bit sound support be included in I DVD 06 and these persistent audio issues put to rest once and for all? Is there some overwhelming technical reason why it cannot be done?

I don't know about overwhelming, but the DVD specification (which was not developed by Apple) calls for the audio to be sampled at 16-bit/48KHz (I think you might also be able to use 96KHz as well). This is what the software expects. If you choose to use another sample rate then the software may or may not be able to "fix" it in post. The real problem is that many camcorder manufactures set the audio to 12-bit by default.
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