AC3 Questions

[iparout]

Hi.

I did a search around the forums and found out that many people prefer to leave the sound in .ac3 format in their DivX rips in order to benefot from the 5.1 sound that AC3 offers.

I have some questions regarding that :

1) Which media players can playback .ac3 sound in DivX files ?

2) When playing back the DivX file from your PC, does your sound hard need to have AC3 decoding support in order to play it correctly ? Will my Sound Blaster Live support that ?


Thanks in advance.

[Snakeisthestuff]

1.) normally i would say every player could. iam watching my divx+ac3 movies with mplayer2, infact i watch all my movies with mplayer2 and got never problems. i have an creative soundblaster live 5.1!.
you only need the correct Decoder, i think there are 2 good AC3 Decoder that i know, 1. AC3Filter, 2. Moonlight Oudio Decoder.

2.) i think you will need an SPDIF output or an card who has an audio decoder and an 5.1 analog output. i have connected my 5.1 Creative Inspire 5300 analog to my Audio card, and it works fine, but Win98 didnt support 5.1 sound, you need Win2k or WinXP. and you need the newest driver updates for your soundcard, cause Creative Soundcards are a little tricky to set up. and if you mux divx with ac3 you must set specific interleave settings or your movie playback will be jerky.

see the great AC3 Q&A http://forum.doom9.org/showthread.php?s=&threadid=18318, there should be all answers you will seek after.

[SkaDood1]

As snake said, it depends on the decoder(also sometimes called directshow filters) they are *.ax files that tell the player how to decode and where to send the data. Get AC3Filter from http://ac3filter.sourceforge.net/ or install get and install PowerDVD. Both of these should let you output an ac3(to S/PDIF) stream to your 5.1 soundcard.
Regarding your soundcard though, I do not beleive it is 5.1 compatible. It has 4 speaker output and you can set that in the respective filter taht you use. I personally send a 5.1 ac3 stream though a 5.1 sound card to an exterior decoder(pansonic receiver) downstairs to watch movies in a totally different room. Its a nice setup:-)

Hope the explanation helps,
-Nick-

[solymi.hu]

I'm looking for a filter for decoding dolby surround stream (from AC3 2.0 or from mp3)without additional hardware and send it through a 4 channel system. Intervideo and Moonlight decoders don't do it! DO THEY?

[rjamorim]

Originally posted by solymi.hu
DO THEY?

NO THEY DON'T!

[MaTTeR]

AC3filter doesn't handle that function? The new 0.6b has alot fo new features such as downmixing but not sure about "upmixing"(LOL..is that a word?).

[Snakeisthestuff]

@solymi.hu
use Tombrettworks ChannelDownmixer and load your desired mixmatrix.
i use this great decoder, to get an 5.1 upmix from any stereo source.

get it here + Alestrix mixmatrix:

http://forum.doom9.org/attachment.php?s=&postid=222399

[solymi.hu]

Snakeisthestuff:
hmmm. I'v tried ChannelDownmixer.
Playing 5.1 AC3 to 4 channel it's oke.
5.1 to stereo Quasi-Dolby Surround Pro Logic downmix.mixmatrix, it'
oke.
Stereo to 5.0 Quasi-Surround upmix.mixmatrix, it's really a quasi sound: the same left and right front channel stream sounds from rear :-( No surround decoding!

[Snakeisthestuff]

@solymi.hu
yeah but its a first step and i hope somebody will get it working with surround decoding soon ;o)