Audio Drift using MP4/AAC

erichrudolph wrote on 12/24/2012, 7:17 PM

I'm ripping a Blu-Ray's audio only to MP4/AAC using a popular rip program, and am ripping it twice: once from PCM/5.1 and once from AAC/5.1, both times to Dolby ProLogic II, 160kbps. If I put these files into graphedt and decompress them to an AVI file (in order to contain the audio, uncompressed) and play them back, they sound "perfect". If I load them into Vegas Pro 11 or Vegas Movie Studio 12, they (a) skip fairly often during playback, sounding "slightly mangled", but only a little, and (b) drift compared to each other, starting off fine, but then having a major drift.

Thus, I think the MainConcept AAC inside Vegas aren't dealing with this audio correctly. I have yet to try another audio or video editing program, but it seems like there's a serious problem in Vegas. I don't know if it's just during audio playback preview or when it's render-to-disk too (haven't tried render-to-disk), but I think the issue is significant.

Any people from Sony want to comment?

Comments

musicvid10 wrote on 12/24/2012, 8:20 PM

Whoa. Unlikely you'll get a response from Sony because:
1) This is a peer forum.
2) You already used third party software to re-encode the audio.

You did not "rip" your audio program. You re-encoded it. AAC is not a BluRay audio codec.
http://en.wikipedia.org/wiki/Blu-ray_Disc#Audio

So, you've made multiple lossy AAC encodes? And, you probably used faac inside your "popular rip program."

Instead, why don't you rip/decrypt your BluRay au naturel, and import the pristine audio program into Vegas?

If you would like others here to suggest better workflows, post your original BDAV .m2ts file properties using MediaInfo from Sourceforge.

BTW, welcome to the forums.
;?)