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My AC3 Codec is not working. Help!

Hello,


I have Perian as my AC3 Dolby Codec and it was working fine until I upgraded to Mountain Lion. Does anyone have advice on what can be done? It seems as if there arent any Dolby AC3 codecs compatible with Mountain Lion. If anyone can help, I greatly appreciate it.


Thanks!

MacBook, Mac OS X (10.7.3)

Posted on Jul 30, 2012 6:28 PM

Reply
85 replies

Oct 3, 2013 12:17 PM in response to William Stanton

Yeah, the Apple "Security Update" then most likely…

While I have run accross several reports of the security updates causing previously playing files to suddenly stop loading and playing, I have never seen a report of a security update taking control of a hard drive and forcing it to corrupt files.



Yes, that's exactly what they did, to give the simulated effect that the sound is being output correctly… I still have it that way because like I said earlier, I want to hear the audio as intended. Before that, I simply had the actual speaker wires swapped instead. Essentially the same thing and without an actual fix, that's all I can do. So, yeah, the audio channels are still reversed… It just doesn't sound like they are because they're in turn reversed again in the MIDI Setup (i.e. channel 1 is channel 2 and vice versa). Hope you get it now…


The other thing you're not understading is the reversed audio channel problem is System-Wide and has nothing to do with QuickTime Player, VLC or any other "Player" at all. If I reset the MIDI settings back to default as you sugest and then open SYSTEM PREFERENCES from the APPLE MENU and then go to SOUND and click on the OUTPUT tab there's a speaker balance bar. If I then slide it to the RIGHT SIDE, I hear the little the "confirmation noise" through the LEFT SPEAKER and vice versa… So once again, the channels are swapped in the MIDI Setup in order to make the SYSTEM SOUND appear correctly to my ears. And regardless of the MIDI setting the channels are still reversed on the MICROPHONE/LINE-INPUT as well. I know all about swapping the channels of an audio file in QuickTime Player, in fact I've fixed one of my tape rips that way. Opened up each track, swapped the channel assignment in the properties window and saved as new files. For now though, I just swap the RCA plugs on the record player (white to red and red to white) so when the mac swaps them during input, it's actually fixing them istead…


P.S. I also mentioned before just copying a CD with iTunes results in an MP3 file with swapped audio channels as well.

Sounds like you are suffering from a self-inflicted wound.


1) You created stereo source files which were encoded with stereo channels reversed.

2) Rather that fix the encoding problem, you changed the global speaker settings to correct the symptom of your Left/Right channel encode issue.

3) You then use iTunes to transcode files with incorrect Left/Right channels to MP3 files which still contain reversed Left/Right channels but sound correct because you are still playing them back using your global reversed Left/Right speaker settings.

4) You then burn the MP3 files with incorrect channels to a CD.

5) You then play the CD with MP3 files incorrectly encoded Left/Right channels on your car's audio system which I assume you have not modified in some way, shape, or form to correct the symptomatic playback problem of your original files which were never corrected.

6) You know how to fix the files properly but choose not to do so but seem to be posting comments here that reflect a bit of frustration on your part. (I.e., I still have not figured out what your "free email for life" comment is supposed to refer to above.)


When I posted previously, I was trying to understand whether you wanted to fix the original problem or just fix the symptom. But all is clear now and I will leave it to you to decide what you really want to do here.


User uploaded file

Oct 3, 2013 9:27 PM in response to Jon Walker

wow, you still don't get it?


1. Launch "Audio MIDI Setup" App

2. Verify channels are set correctly

3. Close "Audio MIDI Setup"

4. Launch "System Preferences"

5. Click on "Sound"

6. Test speaker channels with balance slider

7. Channels are reversed…


Once again, it's a System-wide problem. The entire Mac is effected. Not just iTunes or just MP3s or just QuickTime or anything else. Everything! And I never burned any MP3 files to a CD. I burned the original lossless files as an Audio CD after I swapped their channels. And then I compared the burned CD with the original cassette tape on an actual stereo. I was only giving you some other examples. Such as iTunes also encodes with the channels swapped as well as the line-in. To show that it's not only the speaker output that's swapped but all aspects of auido on the Mac as a whole. Regardless of the MIDI settings, the left and right audio channels in every app (or no app at all) are swapped. Video games, YouTube videos, EVEN PRESSED CD's listened to in iTunes, QuickLook, QuickTime Player, VLC, etc, etc. Left and right are swapped. The only way to listen to ANY SOUND on my Mac is to swap the speakers themelves, or swap them in the MIDI setup. And the reason I only "fixed the files properly" once is because its by far easier and much less time consuming to simply swap the RCA plugs (red and white) on the OUTPUT of the record player when recording because the INPUT is also swapped. In other words, swapping the channels before they hit the Mac, result in a recording with the left channel on the left and right channel on the right, which is what I want… It's been looked at by all three local Apple stores here. Please do those seven steps on your Mac first. I'm afraid if you don't understand that part, you'll never be able to help me… And no offense but only long-time Mac users will get the email joke ;P

Oct 4, 2013 4:05 PM in response to William Stanton

wow, you still don't get it?


1. Launch "Audio MIDI Setup" App

2. Verify channels are set correctly

3. Close "Audio MIDI Setup"

4. Launch "System Preferences"

5. Click on "Sound"

6. Test speaker channels with balance slider

7. Channels are reversed…

I honestly don't know how to explain things any more simply. Will, therefore, go through your list and, for the benefit of other users not already familiar with this process, make some additional amplifying comments of my own.


1. Launch "Audio MIDI Setup" App

I totally agree. The first step is to ensure your system hardware is properly configured.


2. Verify chennels are set correctly

Not really sure what you want people to do here. What I recommed is that people check to ensure their speakers are wired correctly. To do this, press the press the "Configure Speakers..." button under the "Output" tab. When the new window opens, press the "left front" and "right front" buttons under the "Stereo" tab to generate white noise audio signals and observe through which speaker the noises are played back. If you are in the default configuration mode (left front = Channel 1 and right front = Channel 2) then pressing the "left front" button will send sound to your left speaker and pressing the "right front" button will send sound to your right speker. If it doesn't, then your speakers are reverse wired and you really should change their wiring. In this configuration your system should match the configuration of all other users running the default configuration, all properly encoded files (Left channel source audio input recorded to Stereo Channel 1 and Right channel source audio input recorded to Stereo Channel 2) will play correctly in all media applications, and the System Preferences > Sound > Output Blalance slider will work normally. If, on the other hand, you have a large number of files encoded improperly (Right channel source audio input recorded to Stereo Channel 1 and Left channel source audio input recorded to Stereo Channel 2) and opt to reverse your MIDI speaker configuration, then be aware of the following: while all incorrectly recorded files played in non-QT 7 media apps (e.g., VLC, QT X, iMovie, GarageBand, iTunes, etc.) will ignore any embedded QT 7 channel assignments and play correctly, all properly encoded files will play with Left-Right channels reversed, the System Preferences > Sound > Output Blalance slider action will be reversed, any files played in QT 7 apps (QT 7, QT 7 Pro, MPEG Streamclip, etc.) will ignore your MIDI app settings and play the file content according to their embedded chennel assignments, your system configuration will not match that of most other users and most files shared to other systems or devices will play differently on those systems and devices than they do on your system. In any case, no matter how you opt to configure the MIDI Setup app, press the "Apply" button if not grayed out to apply any changed settings to your system before pressing the "Done" button to close the "Configure Speakers..." window.


3. Close "Audio Midi Setup"

Nothing to add here.


4. Launch "System Preferences"

No problem with this either.


5. Click on "Sound"

Go for it.


6. Test speaker channels with balance slider

Okay, here is where I ran into some problems. First of all, whether or not you have a "balance slider" to play with actually depends on how your speakers are connected to your system. In my case, I was using the optical output to connect to a Logitech digital decoder-amplifier-speaker hardware complement and this device has no device control options. So it was quite a while until I finally figured out that I had to disconnect the cable from my system to allow the system to enable the internally built-in speakers before I was able to access a "balance slider" and duplicate your stated workflow. This is also where I discovered that it is the Audio MIDI Setup app that was controlling the slider action. Basically, Apple's labeling of the slider leaves something to be desired since the Left/Right labels are, in this case, relative to the Audio MIDI Setup app channel preferences. In the default configuration, the slider action is normal with the "Left" label representing Stereo Channel 1 audio and "Right" label representing Stereo Channel 2 audio. Thus, when you reverse the Audio MIDI Setup app's speaker configuration preference, you are also reversing the slider action with respect to the Left-Right labels.


7. Channels are reverse...

Based on this comment, I suspect that when you said you were confirming that channels are set correctly, what you really meant was that you were confiming the channels were set correctly relative to a file being played back at the time and not set correctly based on an absolute harware generated signal reference. If true, then I further suspect that your Audio MIDI Setup app speaker configuration looks like this


User uploaded file


rather than this


User uploaded file


which would explain why your balance slider action is reversed.



And no offense but only long-time Mac users will get the email joke ;P

No offense taken, However, I might point out that my original DotMac, now defunct MobileMe, and current iCloud account email addresses all remain valid. (I.e., the Apple mail server still redirects email using older addresses to me so I don't see a problem.)



Please do those seven steps on your Mac first. I'm afraid if you don't understand that part, you'll never be able to help me…

As noted above, I have performed the steps you listed. My system hardware (in terms of reference signal generation) is correct, my speakers are connected correctly, I am running the default Audio MIDI Setup Speaker Configuration which matches nearly all other systems in use, the external speaker interface is delivering 1 to 6 channels of audio as encoded from the original source inputs, and my stereo playback is correct as recorded and/or "hard" cross-coded. The only issue I might complain about is the fact that only the QT 7 and MPEG Streamclip media players support QT 7 Pro "software" channel assignments—but since QT 7 is my primary player, this is not really an issue. Lastly, I do not suffer your System Preferences > Sound reversed "balance slider" issue. Rather than debating my understanding (or lack thereof) of your problems, let's try a simple experiment....


http://downloads.walker4.me/downloads/Temporary_files/DVD-Audio%20Test%20Norm.mo v


The above URL points to an MOV file containing H.264/AAC content. I know the file is correctly hard encoded for correct playback in any media player capable of handling this file type and compression formats. If the file plays correctly on your system, then it is properly configured. If it does not play correctly, then your system is either incorrectly configured or you have a system malfunction. By "play correctly" I mean that the speaker playback display references should match the actual Left/Right speaker playback channels. Feel free to download and test the file in anay and all media players installed on your system. It even plays correctly in my system's browser plug-in player.


What are your playback results?


User uploaded file

Oct 4, 2013 11:38 PM in response to Jon Walker

2. Verify channels are set correctly

By correctly I mean Channel 1=Left, Channel 2=Right (Default).


With the MIDI settings configured as in step 2 (Default), the Balance Slider in the Sound Preference Pane behaves in the opposite way (Right and Left are swapped). My speakers are verified as plugged in correctly. I even tried it with headphones… Leaving it this way (again on the default setting of L=1, R=2), the audio is swapped in your video using QuickLook/CoverFlow/Preview, QuickTime Player X (128), QuickTime Player X (131), QuickTime Player 7.6.6 (1710), QuickTime Player 7.6.9 (1680.8), QuickTime Player 7.7 (1680.25), VLC 1.1.12, VLC 2.1.0, MPlayer Extended rev15-test1, MPlayer 1.0rc2, MPlayer X 1.0.17, MPEG Streamclip 1.9.3b8, FrontRow 1.1, iTunes 10.7.21, DivX Player 11.2.0.81, Roxio Video Player 1.0.3, PresentMovie v1.43, RealPlayer 12.0.1 (1750), Safari 5.1.10 (6534.59.10)


With the MIDI settings configured backwards, per Apple (as Channel 1=Right, Channel 2=Left), the Balance Slider in the Sound Preference Pane now behaves as intended (Right is Right, Left is Left). Leaving it this way (backwards), the audio is now correct in your video using QuickLook/CoverFlow/Preview, QuickTime Player X (128), QuickTime Player X (131), VLC 1.1.12, VLC 2.1.0, MPlayer Extended rev15-test1, MPlayer 1.0rc2, MPlayer X 1.0.17, iTunes 10.7.21, DivX Player 11.2.0.81 and still swapped in your video using QuickTime Player 7.6.6 (1710), QuickTime Player 7.6.9 (1680.8), QuickTime Player 7.7 (1680.25), MPEG Streamclip 1.9.3b8, FrontRow 1.1, Roxio Video Player 1.0.3, PresentMovie v1.43, RealPlayer 12.0.1 (1750), Safari 5.1.10 (6534.59.10). The Speaker Balance slider in the Sound Preference Pane now functions as intended (Right is Right, Left is Left).

Oct 5, 2013 12:31 AM in response to Jon Walker

"No offense taken, However, I might point out that my original DotMac, now defunct MobileMe, and current iCloud account email addresses all remain valid. (I.e., the Apple mail server still redirects email using older addresses to me so I don't see a problem.)"


I don't know if you followed the link I provided to some old comments from 2002 or not but anyway, when iTools first came out, back in 2000, a mac.com email address was free. They later removed all references from their online documentation that implied it was to be "free for life" and decided to start charging $99 per year to continue using your account that had been free for the last two or years. Those of who never paid were eventually locked out and to this day still recieve the following message after attemping to login: "This account has been disabled for security reasons."

Oct 5, 2013 4:41 AM in response to William Stanton

2. Verify channels are set correctly

By correctly I mean Channel 1=Left, Channel 2=Right (Default).


With the MIDI settings configured as in step 2 (Default), the Balance Slider in the Sound Preference Pane behaves in the opposite way (Right and Left are swapped). My speakers are verified as plugged in correctly. I even tried it with headphones… Leaving it this way (again on the default setting of L=1, R=2), the audio is swapped in your video using QuickLook/CoverFlow/Preview, QuickTime Player X (128), QuickTime Player X (131), QuickTime Player 7.6.6 (1710), QuickTime Player 7.6.9 (1680.8), QuickTime Player 7.7 (1680.25), VLC 1.1.12, VLC 2.1.0, MPlayer Extended rev15-test1, MPlayer 1.0rc2, MPlayer X 1.0.17, MPEG Streamclip 1.9.3b8, FrontRow 1.1, iTunes 10.7.21, DivX Player 11.2.0.81, Roxio Video Player 1.0.3, PresentMovie v1.43, RealPlayer 12.0.1 (1750), Safari 5.1.10 (6534.59.10)


With the MIDI settings configured backwards, per Apple (as Channel 1=Right, Channel 2=Left), the Balance Slider in the Sound Preference Pane now behaves as intended (Right is Right, Left is Left). Leaving it this way (backwards), the audio is now correct in your video using QuickLook/CoverFlow/Preview, QuickTime Player X (128), QuickTime Player X (131), VLC 1.1.12, VLC 2.1.0, MPlayer Extended rev15-test1, MPlayer 1.0rc2, MPlayer X 1.0.17, iTunes 10.7.21, DivX Player 11.2.0.81 and still swapped in your video using QuickTime Player 7.6.6 (1710), QuickTime Player 7.6.9 (1680.8), QuickTime Player 7.7 (1680.25), MPEG Streamclip 1.9.3b8, FrontRow 1.1, Roxio Video Player 1.0.3, PresentMovie v1.43, RealPlayer 12.0.1 (1750), Safari 5.1.10 (6534.59.10). The Speaker Balance slider in the Sound Preference Pane now functions as intended (Right is Right, Left is Left).

Very interesting. Based on your results, it would appear that Stereo Channel 1 in the file is being decoded/processed as if it were Stereo Channel 2 (Right Channel data) and vice versa. On the good side, it appears that everything is being processed normally, albeit in reverse. The next question is whether or not your inputs are also being reversed. It is important to determine this in order to know if your recorded files are directly compatible with other systems and devices. My guess is that if you currently have to cross inputs to get proper playback throught your current customized speaker configuration, then your line inputs are also reversed. On the other hand, if you plug in your inputs in the normal manner (left to left and right to right) and get the same results as with the test file, then I would assume your inputs are correct and files are being recorded normally with left channel data being recorded to Stereo Channel 1 and right channel data to Stereo Channel 2. In any case, have never heard of anyone having this particular problem before.


User uploaded file

Oct 5, 2013 5:10 AM in response to William Stanton

I don't know if you followed the link I provided to some old comments from 2002 or not but anyway, when iTools first came out, back in 2000, a mac.com email address was free. They later removed all references from their online documentation that implied it was to be "free for life" and decided to start charging $99 per year to continue using your account that had been free for the last two or years. Those of who never paid were eventually locked out and to this day still recieve the following message after attemping to login: "This account has been disabled for security reasons."

Did read the web artical and did have momentary pangs of nostalgia reading some of the terms/references. (Seti@home—now there's a word I havent seen in years.) Did not, however, realize that iTools had originally been developed by Apple. (I.e., I use PhoneView.) If true, then I assume Apple must have sold the rights to a third party. (Either that or the iTools reference I found on the Internet is something completely different.) In any case, when Apple switched to the "iCloud" I decided to set up my own personal dedicated server so I wouldn't have switch to some new Apple service sometime in the future. Am also running a 3 TB LeCie CloudBox—again to avoid commercial services over which I have no control.


User uploaded file

Oct 6, 2013 1:52 PM in response to Jon Walker

Yeah, I figured you've never heard of this problem before. Apple themselves can't even fix it… And yes, the channels on the Line-Input/Microphone Input are also backwards. I have to swap the left and right on the output of my record player and tape player when recording to the Mac. Also another issue for example, if I convert old .WMA files using EasyWMA, the audio channels are swapped there too… Like I said, ALL audio seems to be swapped: Input, Output, System Sound (and any new audio files created, or converted with anything)…


As far as the Apple iTools, you're obviously thinking of something else. PhoneView is for copying files from your iPhone, where as iTools was a suite of Apps for the Mac, which included iCards, iDisk, HomePage, KidSafe, and a "free for life" mac.com email address… then later became MobileMe and now known as .Mac (this was nearly 15 years ago)!



User uploaded file


User uploaded file

Jan 3, 2014 6:40 AM in response to JSBillian

When you install Perian 1.2.3, it removes the A52Codec.component and AC3MovieImport.component files from /Library/... folders, and places A52Codec.component (ver 1.8.0.) and AC3MovieImport.component (ver 1.7.9) into the respective ~/Library/... folders. I found that the problem was the A52Codec.componet version which seems to not decode AC3 in quicktime 7. I managed to get hold of an earlier verion of that file, (like ver 1.7 6) and replaced the 1.8.0 version file, ...and AC3 sound codes play in Quicktime 7. After such changes were made, you will notice in Perian preference, the button "update perian" will appear. Do not update, doing so will revert the A52Codec.component file to ver 1.8.0.


Try it. Works for me.

Jun 10, 2014 9:50 AM in response to Vietwoojagig

My OS version was also 10.9 Mavericks. Currently I have updated to 10.9.3, and my AC3 encoded movies still play with sound.


Make sure only the file, A52Codec.component (my version 1.7.6) is in the user folder ~/library/audio/plug-in/components/ folder, and the files, AC3Movieimport.component (my version 1.7.9) and Perian.component (ver 1.2.3) are in the user folder ~/library/quicktime/ folder. The above files need not appear in the similar sub-folders of the main library directory. It's ok if present but must not be of version 1.8.0. Best to remove them if present (both A52Codec and AC3Movieimport components, that is). You may need authentication to do this, as you are modifying a system folder.


Hope this helps you.

Jun 11, 2014 2:53 AM in response to tmkee

Unfortunately it does not work for me.

I did exactly as you said. But no audio. In the movie properties of Quicktime 7 it shows:

User uploaded file

ID 3 shows format=AC3 but size and data rate = 0.


I tried a lot of combinations, in the users' library and in the global libary, using:

  • A52Codec.component (1.7.6-20070702)
  • A52Codec.component (1.8-20110723)
  • A52Codec.component (1.8-20120727)
  • A52Codec.component (1.8.1-20121112)
  • AC3MovieImport.component (1.7.6 20070702)
  • AC3MovieImport.component (1.7.9 20110723)
  • Perian 1.3.2
  • Perian 1.2.3


I even tried it on two different machines (both with 10.9.3) and switched my account to admin.

Nothing worked for me.

😢

Jun 11, 2014 8:24 AM in response to Vietwoojagig

Sorry to hear that it does not work for you. Looking at the movie info, it seems the movie file may have encoding problem. Try playing it with VLC and see if it plays. If it doesn't, then it is definitely the movie file. Whether AC3 plays or not on quicktime 7, the size and bitrate values shouldn't be 0. Zero means it has no data. Try other movie files encoded with AC3 sounds on Quicktime 7, where those values are not 0.


If it still doesn't works, I'm sorry I cannot offer much more help. Just out of curiosity, is there a Perian version 1.3.2?

My AC3 Codec is not working. Help!

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