Can the A-110 and C-200 do realtime decoding of 5.1 AAC sound to dolby digital 5.1?

[rogajoga]

As title,

Is this possible, would really like to know?

Many thanks in advance

[Specter]

No.

You can however convert the AAC 5.1 to AC3 5.1. Generally AAC 5.1 can only be experienced on a computer, or most likely a Apple product.

Read the Wiki
http://www.networkedmediatank.com/wiki/i...oconverter


I know those movies floating around the torrent sites look tempting because the are around 1.36GB and full 720P quality but with you notice that the audio is AAC 5.1 you know that you will be limited on the full experience due to stereo downmixing.

Stay away from the 720P AAC 5.1

[peterjcat]

Definitely not. On-the-fly transcoding to Dolby Digital is not on the cards.

The A-110 can't even decode 5.1 AAC to 5.1-channel PCM, only to stereo. No idea about the C-200.

[BuddyBoy]

I bet the 864x processor in the C-200 could do it. It has three 333MHz DSPs compared to the two 300MHz DSPs in the 863x, plus its MIPS general purpose CPU is about twice as fast. That could be enough additional resources to be able to decode the 5.1 AAC to six channels of PCM on one DSP and encode it to 5.1 AC3 on the other in real-time.

Whether that will be a supported feature is a completely different question.

[spawn]

It wont - license to Dolby for 5 channel encoding are considerable and seriously not worth the cost increase of the product just to support the few users that cant be bothered downloading stuff that works allredy using ac3/dts, or stuff that works with whatever receiver they have, or be bothered to buy a receiver that matches their needs. I dont want to have to pay extra for my mediaplayer to support these users. No offence intended.

Multichannel audio are supposed to be bitstreamed and decoded at the receiver end for optimum audio processing - not supposed to be converted to AC3 in real time at the player level (atmost it get decoded to multichannel PCM - but never converted to AC3). Nothing else out there does this either (yes I know about the xbox360 but lets not get into that - they only do it to overcome their own Microsoft limitations/failures with wmv 5.1)

[rogajoga]

Well the plex player which is a fork of xbmc on the mac does AAC 5.1 to dolby digital 5.1 real time encoding, but of course you need either a apple tv with patchstick or mac computers like the mac mini. Even if the c-200 could support AAC 5.1 to 5.1 PCM that would be pretty awesome. The problem is it's all about hard drive space, yes I could make a load of backups of my dvd collection but getting good quality out of them with ac3 5.1 sound will come to about 1.4GB in size (2CD's). If I had AAC 5.1 we could be looking at 1GB in total. Now 500 movies of mine backed up saves me around 400GB on HDD space. Now I could choose whether I wanted to play that AAC 5.1 track from my 1GB backup with real time encoding to ac3 5.1 or to 5.1 PCM. When you look at comparing this amount of movies to people with a collection of say 2000 movies the HDD space saving is huge and saves people with not so much money having to go out and buy so many hard drives.

[peterjcat]

Plex does it without a licence, which may be OK for a non-commercial project but isn't something Syabas etc would risk. I think you're overestimating the efficiency benefits of AAC vs AC3 somewhat; though AAC is more efficient you're not going to save 40% on the overall filesize. Considering 400GB costs something like $40 it's not really worth it for most people.

If you have HDMI then with any luck the new PCH will decode 5.1-channel FLAC to multichannel LPCM which should give some space savings.

[spawn]

(06-23-2009 12:17 PM)rogajoga Wrote:  Well the plex player which is a fork of xbmc on the mac does AAC 5.1 to dolby digital 5.1 real time encoding, but of course you need either a apple tv with patchstick or mac computers like the mac mini.

C'mon - whatever you can do more or less unofficially or maybe even illegally without licensing using software on computers are completely irrelevant for a commercial hardware player.

(06-23-2009 12:17 PM)rogajoga Wrote:  Even if the c-200 could support AAC 5.1 to 5.1 PCM that would be pretty awesome. The problem is it's all about hard drive space, yes I could make a load of backups of my dvd collection but getting good quality out of them with ac3 5.1 sound will come to about 1.4GB in size (2CD's). If I had AAC 5.1 we could be looking at 1GB in total. Now 500 movies of mine backed up saves me around 400GB on HDD space. Now I could choose whether I wanted to play that AAC 5.1 track from my 1GB backup with real time encoding to ac3 5.1 or to 5.1 PCM. When you look at comparing this amount of movies to people with a collection of say 2000 movies the HDD space saving is huge and saves people with not so much money having to go out and buy so many hard drives.

If you do not plan to keep the original AC3 track but will spend the time to convert them to 192kbps AAC to save space, then you could just as easily convert them to 192kbps AC3 to save the same amount of space. The format being AC3 instead of AAC does not in itself conclude it takes up more space.

[daniel_owen_uk]

Technically what you are asking is not a decode, it's an encode.

[spawn]

Not that theres anything wrong with the idea of decoding on the player as such - its just the decoding has to be done somewhere - the license cost are the same no matter where its done. So either you design a very expensive player that decodes everything by adding the licenses on the player cost, or you design an external receiver/decoder and pay the license cost there.

The general consensus is that its the external receiver that gets designed for good audio handling and thus has the license costs and the decoders for the different formats - and you buy a receiver that meets the decoding specs you need and just bitstream the audio from any player to it.

Could be the other way around but the overall cost of player + amp will be the same. Like do you want a $1000 player and a $200 amp, or a $200 player and a $1000 amp

Since I would normally have more players than Amps, Id prefer to only pay the cost once on the Amp, rather than having to pay licensecost for multiformat decoding on every player I connect.

[rogajoga]

(06-23-2009 12:33 PM)peterjcat Wrote:  Plex does it without a licence, which may be OK for a non-commercial project but isn't something Syabas etc would risk. I think you're overestimating the efficiency benefits of AAC vs AC3 somewhat; though AAC is more efficient you're not going to save 40% on the overall filesize. Considering 400GB costs something like $40 it's not really worth it for most people.

If you have HDMI then with any luck the new PCH will decode 5.1-channel FLAC to multichannel LPCM which should give some space savings.

Does the c-200 support multi channel FLAC?

Is FLAC as good as AAC?

[daniel_owen_uk]

Much better.

FLAC is lossless, filesize won't be as small as AAC, but will be better quality.

[BuddyBoy]

The old NForce2 motherboard chipset from NVidia featured real-time Dolby Digital 5.1 encoding. That feature was dropped from all their later products in favor of HD Audio support.