Welcome to Doom9's Forum, THE in-place to be for everyone interested in DVD conversion.

Before you start posting please read the forum rules. By posting to this forum you agree to abide by the rules.

 

Go Back   Doom9's Forum > General > Audio encoding

Reply
 
Thread Tools Search this Thread Display Modes
Old 14th June 2004, 08:06   #1  |  Link
Tony Maroni
Registered User
 
Join Date: Jun 2004
Posts: 13
EAX over SPDIF. ..Is it possible?

Hi there!

I've done quite some research, but didn't find anything that will really fulfill my needs...

Well some months ago i bought an Audigy. My PC stands in the workroom, with an analogue 5.1 PC-Speakerset. No problem until here, but it's also connected with the TV and the Dolby Digital receiver in the livingroom (via S-VHS and digital coaxial). DVDs work great, I can watch them on the TV with great AC3 sound.

But the thing that sucks are EAX-Games. Over SPDIF output i can only get stereo PCM, because there is no soundcard on the market (besides NVIDIA soundstorm(DICE), but thats a mainboard...) that can do real-time AC3 encoding...
But on-the-fly-AC3-encoding is possible with todays hardware, I found the Direct-Show AC3-Filter (rc5) that can do exactly the same thing!!
It takes every multichannel-input (with 48000 khz) and transforms it to AC3 while listening....

Is there a programm to catch the EAX-game multichannel sound ( a prg that pretends to be a sound output device for example), transform it to 48000 and handle it over to AC3-Filter... This would be like a dream coming true...
Or am I only dreaming and this will never be possible??
Any advice from you PROs would be very handy!!

Thanks for your brainpower!
Tony Maroni is offline   Reply With Quote
Old 14th June 2004, 08:46   #2  |  Link
E-Male
mad computer-scientist
 
Join Date: Mar 2002
Posts: 1,375
all free realtime ac3 encoders are in their early stages
it'll take time until they are mature

encoding the EAX audio tro ac3 should be possible
maybe creative will try to block such programs (maybe not)

i think it's just a matter of time, not sure how much
E-Male is offline   Reply With Quote
Old 14th June 2004, 21:58   #3  |  Link
Tony Maroni
Registered User
 
Join Date: Jun 2004
Posts: 13
Why do you think CREATIVE would not be happy with such a program?

I tried to encourage some discussion on this topic (EAX over SPDIF)at the official creative board, and several posters were requesting the same feature.

The only answer i did get was to buy a digital speaker-set from CREATIVE, which is really ridiculous... (don't think their small speakers will match my self-build ones, beside the fact that all needed equipment is standing right there in my living-room, why spend more money???)
Could this be the reason why CREATIVE seems to have no interest in this feature? That would be really poor...

Anyway, good to read that it may be possible in the future, hope the development will go on further...
Tony Maroni is offline   Reply With Quote
Old 15th June 2004, 02:13   #4  |  Link
E-Male
mad computer-scientist
 
Join Date: Mar 2002
Posts: 1,375
guess you answered the question yourself

it would be neccessary to "catch" the seperate channels and send them to the ac3 encoder, all that in realtime
E-Male is offline   Reply With Quote
Old 20th June 2004, 07:33   #5  |  Link
Tony Maroni
Registered User
 
Join Date: Jun 2004
Posts: 13
I read spomewhere "encoding time=decoding time" for the AC3-Stream.
As decoding does not need that much CPU-Power, real-time encoding should be possible on todays hardware, I guess the only problem is the missing software...
Well there's really a need for this kind of utility...
Tony Maroni is offline   Reply With Quote
Old 20th June 2004, 16:19   #6  |  Link
brute
Registered User
 
Join Date: May 2003
Location: germany
Posts: 51
every nForce Mainboard that has the MCP-T southbridge can encode EAX in AC3 and this is sent through S/P-DIF to a receiver. That's how it works for me. The disadvantage is, that nForce only have EAX 2.0 Support.
__________________
I WANT TO BELIEVE
brute is offline   Reply With Quote
Old 20th June 2004, 16:21   #7  |  Link
E-Male
mad computer-scientist
 
Join Date: Mar 2002
Posts: 1,375
there ARE realtime ac3 encoders
the only problem is getting the channels from EAX
E-Male is offline   Reply With Quote
Old 20th June 2004, 17:36   #8  |  Link
Tony Maroni
Registered User
 
Join Date: Jun 2004
Posts: 13
@brute:
Well buying a new mobo is not quite the solution im thinkin' about. I've read about it before, sounds really interesting, but why did they remove it on nForce 3?? That really bothers me...
But I think it must also be possible with other cards in software...

@E-Male:
Yeah, I'm quite aware of that fact(tested new AC-Filter by myself) and that's not what i meant.
I think the CPU usage has to be rather low for real-time encoding, because the EAX games (mostly 3D games...) will use most cpu power, I guess. With stuttering gameplay, there would be no point in using an encoder...

So the real problem is getting the EAX-streams...

Just waitin...

Regards and thanks for your answers
Tony Maroni is offline   Reply With Quote
Old 20th June 2004, 23:41   #9  |  Link
E-Male
mad computer-scientist
 
Join Date: Mar 2002
Posts: 1,375
eax costs much cpu power?
i thought the soundcard would do most of it
E-Male is offline   Reply With Quote
Old 21st June 2004, 18:58   #10  |  Link
Tony Maroni
Registered User
 
Join Date: Jun 2004
Posts: 13
I'm talking about the whole game (3d-engine,physics,KI and so on) that will take much CPU power... Without a running game, there's no real point in EAX sound i guess!

About EAX in hardware:
As far as i know (i didn't find anything official from inventor CREATIVE), on cheap Audigy LS (the card i'm using) EAX is produced by the driver in some kind of software mode mostly. I'v read reports about 30% cpu power used by the driver in EAX mode, but on my system (AthlonXP1600+), everything is fine when turning on EAX.

So there should be some CPU power left for the AC3 encoder...
Tony Maroni is offline   Reply With Quote
Old 21st June 2004, 19:27   #11  |  Link
E-Male
mad computer-scientist
 
Join Date: Mar 2002
Posts: 1,375
like always, if your power isn't enough, you gotta upgrade
maybe when the topic get's more up2date (when eax channels can be cought) realtime ac3 encoders will get some kind of "high quality vs. cpu greedyness" option
E-Male is offline   Reply With Quote
Old 23rd June 2004, 17:05   #12  |  Link
Tony Maroni
Registered User
 
Join Date: Jun 2004
Posts: 13
Well I guess the only problem right now is catching the EAX streams and handle them to AC3-Filter. Is this such a big issue??

There must be tools around that catch the sound stream for recording purposes, i guess. Can these tools record EAX-streams? Then it would be just a little step further, i suppose...

Oh by the way, does anybody know a good EAX related site with explanations and maybe some testing tools for EAX?
Tony Maroni is offline   Reply With Quote
Old 23rd June 2004, 20:37   #13  |  Link
E-Male
mad computer-scientist
 
Join Date: Mar 2002
Posts: 1,375
i'm not aware of any way to record eax output as multichannel
E-Male is offline   Reply With Quote
Old 27th June 2004, 19:25   #14  |  Link
Raptus
heretic nuB
 
Join Date: Sep 2003
Posts: 71
I'd be even more interested in some way of getting multichannel ASIO > SPDIF, maybe using AC3 as "transport", too.
Raptus is offline   Reply With Quote
Old 28th June 2004, 12:54   #15  |  Link
ursamtl
Registered User
 
Join Date: May 2004
Location: Montreal
Posts: 729
Have you guys checked out the kX drivers for Live/Audigy cards? I don't know about the EAX stuff as it's not really my interest, but I do know that they give these cards a new lease on life when it comes to ASIO. Plus they're free. www.kxproject.com.

I've been using them for awhile now and they blow the Creative drivers right out of the water!

Steve.
ursamtl is offline   Reply With Quote
Old 29th June 2004, 00:16   #16  |  Link
E-Male
mad computer-scientist
 
Join Date: Mar 2002
Posts: 1,375
kx isn't the holy grail either (not yet, maybe)
E-Male is offline   Reply With Quote
Old 29th June 2004, 00:45   #17  |  Link
ursamtl
Registered User
 
Join Date: May 2004
Location: Montreal
Posts: 729
Quote:
Originally posted by E-Male
kx isn't the holy grail either (not yet, maybe)
No, not at all, but for ASIO on a Live, it's great! I also like the DSP applet in that you can basically route almost anything anywhere. Try doing that with those bloated Creative drivers.
ursamtl is offline   Reply With Quote
Old 29th June 2004, 11:06   #18  |  Link
Tony Maroni
Registered User
 
Join Date: Jun 2004
Posts: 13
The kx drivers are really quite astonishing, but have no suppport for EAX yet. But thats not so bad, because EAX is only some kind of DSP device( i have learned), the real positioning is done by DirectSound3D. And this is of course supported by the drivers. (with a few bugs i guess?)

But right now, these drivers can't do AC3 encoding on the fly, maybe this will be done in the future.

I think it's far more possible to get the solution we are waiting for from the kx-project than from CREATIVE, so praise open source programmers!
Tony Maroni is offline   Reply With Quote
Old 29th June 2004, 16:16   #19  |  Link
E-Male
mad computer-scientist
 
Join Date: Mar 2002
Posts: 1,375
i read dolby will release a new mobo in the usa that has a realtime ac3 encoder chip on board
E-Male is offline   Reply With Quote
Old 29th September 2004, 21:59   #20  |  Link
NizZ8
Registered User
 
Join Date: Dec 2003
Posts: 1
Is there any new news on this subject? 6ch direct analog sound just isn't working for me. I have substantially lower quality sound when i have to do a 25ft run for an analog signal from PC -> Reciever .

I know the soundcards will output the eax signal through the digital out on the card (for those w/ digital speaker packages).. if there was a way we could grab this and re-encode it...?

Last edited by NizZ8; 30th September 2004 at 00:47.
NizZ8 is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +1. The time now is 14:57.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2017, vBulletin Solutions Inc.