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Discussion Starter #1
I've seen this touched on slightly but have never seen a full and direct answer to the question I have. The new AIT 4800 series cards have the hardware to support full resolution 7.1 HD audio over HDMI but are not PAP compliant and so any HD audio tracks played from an AACS protected Blu Ray or HD DVD disc will be downsampled, that's my understanding anyway. I've seen guides here that recomend ripping discs with AnyDVD and then transcoding the hi def audio tracks to FLAC and muxing the audio and video into an MKV file to preserve the HD video and audio and allow unrestricted playback. However this seems like a far less than optimal solution as opposed to being able to pop the disc in and have full hi def audio. My question is if AnyDVD circumvents AACS protection, assuming I have hardware that supports hi def audio over HDMI like the ATI 4800 cards do, and I have a software player that supports 7.1 full resolution LPCM audio like Arcsoft is supposed to, will I be able to simply pop in a Blu Ray or HD DVD disc and get LPCM HD audio over HDMI without it being downsampled?
 

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No, no solutions today that do that. The players all dwonrez today regardless if they see AACS or not. Stupid but true. This may change in the future, but not today.
 

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AFAIK, all the "legitimate" players always cap you at 16/48k regardless of the presence of AACS.


There have been rumours that that is supposed to change (at least in PowerDVD) in a future update.


But big picture, good luck hearing the difference between 16/48k and 20-24/48k.
 

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Discussion Starter #5

Quote:
Originally Posted by stanger89 /forum/post/14296663


AFAIK, all the "legitimate" players always cap you at 16/48k regardless of the presence of AACS.


There have been rumours that that is supposed to change (at least in PowerDVD) in a future update.


But big picture, good luck hearing the difference between 16/48k and 20-24/48k.

In this case I have a follow up question. Every Blu Ray and HD DVD must have at bare minimum a Dolby Digital or DTS 5.1 audio track to fall back on so to speak if for one reason or another any higher end audio tracks that might be on the disc cannot be played back. If any point in the path between the origin and destination of the audio data isn't protected then only that basic 5.1 Dolby Digital or DTS audio track will be allowed to pass through. Is this what is going on with the software players like Cyberlink and Arcsoft or are they downgrading the audio in some other way and for some other reason?
 

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Quote:
Originally Posted by KTac /forum/post/14298359


Is this what is going on with the software players like Cyberlink and Arcsoft or are they downgrading the audio in some other way and for some other reason?

My understanding is this is the theory.

But PowerDVD plays it safe and downsamples always...



Diogen.
 

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Quote:
Originally Posted by KTac /forum/post/14298359


In this case I have a follow up question. Every Blu Ray and HD DVD must have at bare minimum a Dolby Digital or DTS 5.1 audio track...

Or LPCM.

Quote:
...to fall back on so to speak if for one reason or another any higher end audio tracks that might be on the disc cannot be played back. If any point in the path between the origin and destination of the audio data isn't protected then only that basic 5.1 Dolby Digital or DTS audio track will be allowed to pass through. Is this what is going on with the software players like Cyberlink and Arcsoft or are they downgrading the audio in some other way and for some other reason?

No, the "mandatory" tracks are there to ensure that there is at least one track that can be played regardless of player. Not every Blu-ray player supports decoding or passthrough of DD+, DTHD, or DTS-HD MA. Note that mandatory codecs include LPCM which is equivalent to the lossless codecs. Mandatory tracks have nothing to do with copy protection it's all about compatibility.


Downsampling is done because AACS has a requirement that in the license agreement to not output digital audio at over 16bit/48kHz unless it's an approved digital output. Since there are no Blu-ray discs (and very few HD DVDs) without AACS protection, it was probably simpler to just always downconvert and thus avoid breach of the AACS License Agreement than try to come up with multiple ways of handling audio.


And I've said it a number of times but the whole downconverting issue has been blown WAY out of proportion. Only a handful of discs have audio that's significantly higher sampling than 16bit/48kHz, essentially all are 48kHz, and most LPCM tracks are 16bit and DTHD and DTS-HD MA vary between 20 and 24bit. But it's highly unlikely anyone could tell the difference (in a blind test) and even with the downconversion the audio is still the best we've ever had (and better than the theater).
 

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what does MPC-HC do now? I know it has direct playback of Blu-ray files now. Does it downsample the audio?


The video filters still need some work unfortunately. I get a green line at the bottom of the film and sometimes get a small glitch or two. Not bad for the first release with native support though. Can't wait until they finally get it all working perfectly.
 

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Quote:
Originally Posted by tsb /forum/post/14299309


what does MPC-HC do now? I know it has direct playback of Blu-ray files now. Does it downsample the audio?

Probably not, but does it even decode DTS-HD MA or Dolby TrueHD?
 
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