AC3 Issue with Sony HDR-SR7 MPG files

[jeremyhall]

I have been closely watching this forums hoping to find a fix for my AC3 issue. I have read the various posts about Leopard and the Quicktime update having "broken" the ability to decode AC3 audio, but everything I have read seems to be addressing DIVX/XVID encoded AVIs. I figure I'll through in my situation in hopes that there may be a fix out there or to provide any sample files that may help in the work towards a fix.

I am a recent user to come from the Vista dark side to a Mac Book Pro, only to be very disappointed in Leopard not being able to natively decode the audio from the SD quality MPG files produced by the Sony HDR-SR7. The files are MPEG-2 files muxed with AC3 5.1 sound.

I regularly edit these files quickly for web and DVD production, but have been unable to on the Mac without running them through a MPEG Streamclip batch process. This is a short term fix, but completely unacceptable for me in the long term. The files go through one more step of compression, and in using an intermediate codec at high quality the files are tremendously larger.

Of note, I have tried the output option offered by MPEG Streamclip to convert the files to MPEG-2 with MP2 audio in hopes that this muxed version would still work but with no love.

I would be happy to shoot and provide a sample clip if that would be of any help in getting a fix to be part of a future release, or if someone might be able to guide me towards a more individual solution.

Thanks!

[The_Tick]

I have been closely watching this forums hoping to find a fix for my AC3 issue. I have read the various posts about Leopard and the Quicktime update having "broken" the ability to decode AC3 audio, but everything I have read seems to be addressing DIVX/XVID encoded AVIs. I figure I'll through in my situation in hopes that there may be a fix out there or to provide any sample files that may help in the work towards a fix.

The problem with this is that the sooner you had reported it, the sooner we could have started looking into it. Waiting means it'll be at least 1-3 months before a stable release is put out with anything that would address this. Just a heads up for the future.

[The_Tick]

I would be happy to shoot and provide a sample clip if that would be of any help in getting a fix to be part of a future release, or if someone might be able to guide me towards a more individual solution.

Samples are typically what we need to address issues.

[gbooker]

Are you saying the container format is a MPEG-2 file? If that is the case, then the fault lies with Apple's MPEG component, not Perian. Furthermore, there really isn't anything the Perian can do about this situation.

If it isn't an MPEG-2 file, then what is the container format?

[jeremyhall]

Yes, the format is an MPEG-2 file, but with AC3 5.1 muxed audio. I have the QT component for MPEG-2, but I thought Perian made up for the lack of support for the muxed audio. Perhaps this is my new-to-Mac misunderstanding?

[jeremyhall]

Just in case there is some help to be found, I have posted a sample file of the SD format from this camera.

http://www.smartfamilyteam.com/files/M2U01784.MPG

Again, apologies if I have this wrong due to my lack of understanding. If there is another solution to getting this audio decoded from these files, I would greatly appreciate any direction.

Edit: Also, I forgot to post that VLC does in fact play these files fine (with audio), but QT is necessary of course to edit these files in any editor as they all seem to use the QT engine for decoding.

[gbooker]

Yes, the format is an MPEG-2 file, but with AC3 5.1 muxed audio. I have the QT component for MPEG-2, but I thought Perian made up for the lack of support for the muxed audio. Perhaps this is my new-to-Mac misunderstanding?

This is only the case when QT is actually told that there is any AC3 audio. In this case, the MPEG2 component tells the rest of QT that there is no AC3 audio. Demand that Apple fix this major oversight and you get what you paid for: http://bugreporter.apple.com

[jeremyhall]

Are there any alternatives to the MPEG2 component?

[jeremyhall]

I take the stunned silence as a no, there is no alternative to the official component?