SVideo plus AC3 capture to HD, then later playback.. how?

[TheServerGod]

Forgive my ignorance. I have digital cable, which provides a clean SVideo signal AND AC3 audio through a SPDIF jack. I've got an MSI TV@nywhere card for SVideo capture and a Live! 5.1 Platinum audio card with SPDIF input on the LiveDrive.

I want to be able to timeshift viewing of the many premium channels I subscribe to, and be able to enjoy it in the Dolby Digital some of it comes in. I know how to capture the SVideo.. in fact, I've tweaked the alpha version of Dscaler to give me a great picture.

But I have three problems: I can't figure out how to capture AC3 with the Live! 5.1 Platinum. I've downloaded and installed the latest drivers from the Creative site, and have a proven feed out of the digital cable box and am using a tested coax cable into the SPDIF port on the LiveDrive. But I can't find any settings on the Live! software that get the AC3 audio.

Second is, once I find how to listen to the AC3 audio, how do I capture it in a file that is easily synched up with my Svideo? And what application is best for playback? My primary objective is to timeshift using hard drives, as I'm waiting for DVD-R's to drop in price. (I have 240gigs of HD space, so I've got the room.) Once they do, I'm guessing that DVD is the way to go with this combination of sources.

Regarding the playback of the digital audio signals, I'm hoping someone will advise how the Live! card can do they Dolby Digital decoding on it's own to 5.1 speakers. If not, I do have a separate AV receiver that I can feed from an optical output on the LiveDrive.

Help!

Equipment list:
Asus A7M266 with Athlon 1.33
512 MB 2100DDR
Live 5.1 Platinum
Asus 8200 Deluxe GForce3
MSI TV@nywhere card (don't buy this.. it's tuner is in MONO ONLY)
DVD-ROM & CDRW drives
Window XP Pro

[TheServerGod]

bump

[TheServerGod]

Folks, is this something that's impossible? Or is it something that people do with some kind of "warez" that everyone is afraid to talk about?

It seems like anyone with a sound card, video capture card, and either digital cable or a DBS system would want to know this. Why does no one talk about it?

[TheServerGod]

yet another annoying bump

[TheServerGod]

Hey, I'll keep bumping till I get an answer. I'm an old man. I can wait.

[Nelson37]

The only person I have seen detail a method to successfully capture AC-3 audio was using a $500.00 sound card. SFAIK, it cannot be done unless you have a sound card capable of "bit-accurate" capture.

Several people, including myself, have tried this but I have seen NO info that it can be done with consumer level sound cards.

By using standard audio capture techniques you should get a file which has been downsampled to Dolby Prologic, and you can capture the audio as a PCM file for digital quality, but no AC-3.

SFAIK, most soundcard do NOT decode AC-3, they merely pass it on to an amp or speaker set with onboard AC-3 decoding.

If you want to try, set your SPDIF IN as default sound input, capture with any capable app. You will get a pulsing static which is similar to a true AC-3 file. There are several programs to convert AC-3, or place correct headers on an AC-3 wave file, but they will not accept the captured file.
AC3FIX, GOLDWAVE, COOLEDIT, BESWEET, AZID, HEADAC3HE, there are some others. Do a search on Capture AC-3, good luck and please report back any success or relevant info.

[TheServerGod]

Ok.. $500 for a sound card a year ago might mean $100 now. Any ideas about this? I understand that once captured as an AC-3 file, I can do anything I wish.

I need hardware ideas for this capture.

[Nelson37]

No, I checked the web site, Digi 96 or something like that, it was $479.00 a month or so ago. There is a thread on AC-3 cap at Doom9.org, from some time ago. As to which other cards can do this, no one else has reported success.

He reported that the capture should sound like pure white noise, no pulsing, when played as a WAV. Now I did download a valid AC-3, which on my machine the WAV played the same - pulsing static - as my captured AC-3 tests, but the DL'd file would play correctly, and be identified as AC-3, with WinDVD. It would also run correctly through the file converters I mentioned. My captures, however, would either fail or give a variety of errors, basically indicating an invalid or corrupted file, some indicated something like lost frames. I have tried both broadcast and DVD.

I tested before I got an AC-3 capable amp, have since verified valid AC-3 on cable and DVD, but haven't messed with this in a while. May give it a stab again as I did solve another big problem recently (editing MPG-2 caps) and am feeling lucky.

The similarity and some other info makes me think this could be some sort of timestamp or index problem, and that some combination of conversions or fixes may do it. Though editing and working with these files, even if made accurately, is another problem.

[TheServerGod]

Nelson, I appreciate your follow-up. The LiveDrive on the Platinum 5.1 has an SPDIF IN and is supposed to be able to capture DD. However, you may already know about Creative's poor drivers and customer service. I've been asking them for weeks, and just get a runaround.

I wonder.. will the Nforce2 Soundstorm on the newer motherboards be able to do this?