AC3 audio on BD

DVC wrote on 9/4/2008, 1:29 AM

From what I've read, multi-channel (5.1) LPCM cannot be passed from a BD player to a receiver via SPDIF. The data rate, is simply too high. (Also, bass-management may not function with LPCM.)

Which is why AC3 is used for BD movies -- although other advanced codecs are added.

Sony claims MS9P supports AC3 encoding. Naturally, I expected there would be an AC3 option on the Burn-to-BD function. Yet, there is no AC3 option I can find. Not even for AC3 stereo!

This is true of both MPEG-2 and AVC on BD.

Assuming only LPCM is supported -- how does Sony think you will get the signal to your receiver and get it to switch to 5.1?

PS1: this problem is also critical to playback on computers with BD players. With a USB sound "card" you can send AC3, but not 5.1 LPCM.

PS2: HDMI 1.3 does support up to 8 PCM channels. But, there are very few HDMI 1.3 receivers and no HDTVs with 6 speakers.

Comments

Eugenia wrote on 9/4/2008, 9:49 AM

There is AC3 export support on Plat9, but you need to make sure that DVDA is also installed, as that's the one that offers the codec. However, Vegas doesn't use it in conjunction to BDs, it is mostly used for DVD usage.

DVC wrote on 9/4/2008, 6:07 PM

So, the burn to BD is useless if one is using 5.1 sound. Sony seems to be playing games. The solution is not to buy DVD Arch. Buy Ulead MovieFactory at $50. Then export .ac3 and .m2v files and burn ANY disc -- AVCHD or BD or HD DVD -- from it. With Menus.

Wolfgang S. wrote on 9/5/2008, 10:48 AM

Vegas Moviestudio 9a Platinum has only the AC3 Consumer encoder integrated (the so called Creator). Due to compatibility reasons, that should not be used for BD-R - that is the reasony why you cannot choose that encoder in the burn to disc export option. Vegas Pro 8 has the more expensive AC3 Pro encoder, that can do what you are looking for.

What does not mean that you cannot burn with tricks like the Moviefactory such a AC3 Studio-Encoder footage to a BD-R - that is up to you, off course. But if the disc is compatible is also up to you - and if it works, you are fine.

ggrussell wrote on 9/5/2008, 10:07 PM

What makes the AC3 'consumer' encoder any less qualified for BD-R creation? VMS9 supports 5.1 editing so exactly what are you saying or implying? That the AC3 output in VMS9 for some reason is less capable?

Wolfgang S. wrote on 9/6/2008, 3:56 AM

I cannot explain you the technical differences between the Creator and the professional AC3 encoder really, because I do not know. But from Sonys side I know for sure, that there are limitations. Why do you think is another AC3 Pro encoder in Vegas Pro 8/DVDA5?