Any way to capture RF AC3 from laserdisc?

[oddball]

Anyone figured this one out yet? I keep looking over the last few months and no answer yet. :)

[sebus]

Wouldn't it be nice to be able to do it?

But I believe there is NO way so far, as there is no software to accept input with 6 chanels

sebus

[ChristianHJW]

.. are there really no laser-disc players with digital out ?

[oddball]

Not sure but I do know you can get RF to SPDIF convertors. So the only problem then is capturing the SPDIF digi out from the RF convertor to the SPDIF input on a soundcard and save it as a raw AC3 file. Or even to split it to 6 wav channels. At least then the wavs would all be in sync and you could re-encode to 5.1 AC3 using Soundforge's AC3 encoding prog.

[sebus]

For the info of the reply posters here. RF out & Digital out on LD are two different outputs.
RF outputs AC3 signal in RF format which then gets converted to nornla Dolby Digital in RF Demodulator.
Digital out sends normal digital sound (surround, but NOT AC3).

So getting to Dolby Digital is NOT a problem (with use of RF Demodulator)
But then there is NOT known (at least to me) software that can capture Dobly Digital multichannel audio into any form.

Please correct me if I am wrong (same as one can NOT capture Dolby Digital signal from EXTERNAL player)

Regards

Seb

[crimazine]

I just posted about this in Video Capturing. Thanks for sharing your info here. Looks like bad news for someone looking to capture surround =(. Does anyone suppose its realistic to hook up to all the outputs of a surround receiver and record all 6 channels simultaneously?

- crimazine

[ZYron]

Hi!

I made a easy Test with the Digital out of my DVD Player ... sorry I have no LaserDisk ;) .. Try this:

Hook up the DVD/Laserdisk with your Soundcard
Sample with Cooledit at 48000Hz Stereo 16 Bit.
Save it as PCM Raw Data 16-Bit Motorola PCM (save Dialog Options..)
Rename the file from xxx.pcm to xxx.ac3 ...
This file works with BeSweet and Azid ..

Cya ZYron

[Kandor]

The dolby digital track is something that came to laserdisc very late in its life.
so the standard was there so for them to squeez the dolby digital track in the disc so it would be compatible with old players they did it this way. they but the DD track in analog for on left or right channel of the analog track in the laserdisc ( dont remeber witch one) and by analog I dont mean that it is saved actually as analog but that is nothing I am going to get my self into now, so the RF signal is the analog signal from one of the channels and that signal is actually a digital signal in analoge form so the rf converter is for that signal to be converted to digital.

so I dont think there is anyway you could record that but that is only what I know.

Best Regards
Kandor

[crimazine]

Thanks for sharing your method ZYron! Very encouraging, I'm going to give it a try. I had a hard time understanding Kandor's message but I'm just going to try ZYron's method and see what it sounds like. The Laserdisc player I'm working with is a Pioneer DVL-909 ( http://www.laserdiscarchive.co.uk/DVL-909.htm ) and claims to have Digital Out. It also plays DVD's though so perhaps the Digital Out is only for DVD if indeed there are no Laserdisc players with Digital Out.

Thanks for the great info guys!

- Crimazine :)

[oddball]

OK I tried the method SyRon suggested. Cannot get it to playback though. I am unclear about two things. The capture settings in Cooledit and the way to save it.

I am using Cooledit Pro 2.0 and when I hit record it prompts me for various options like 48000Khz, stereo, 16bit etc. Which combination should I be using? 48000Khz, mono and 16bit? I see the digital sugnal being recorded either way (Though obviously I cannot hear it unless I get a second long cable to loop it back to the decoder/amp maybe).

Then what about saving it? You say PCM RAW right? In the options for saving in PCM RAW there is 16bit Intel PCM something or other, 16bit Motorola PCM, 8bit mu-LAW and 8bit A-LAW. Which is correct?

Merging it into a test DiVX AVI file and playing back in something like BSPLayer using the Intervideo AC3 decoder results in no sound at present althout BSPLayer gives a volume control as if there is audio there. I tested using a DiVX with AC3 that I know works just before performing these tests so it's not my setup ;)

Any help appreciated as I find this interesting.

[ZYron]

Hi oddball,

for Sampling use 16bit 48000Hz stereo ! This works here :)
When you Play this File in Cooledit it sound´s like white noise (check it with frequency analysis, should be around -28db for the whole spectrum).

Save the File as PCM Raw Data 16-Bit Motorola PCM !!!

Don´t merge this File with AVI/DIVX .... its too big !
Between each AC3-frame is about 4352 bytes space !
Filesize is like uncompressed Wave at 48000Hz.
You have to transcode it with Besweet or decode it with Azid.

CYa ZYron

[oddball]

Hmm. Not having much luck here. Did exactly as you said but when I try to transcode it in BeSweet it comes up with a bunch of errors about CRC and incorrect frames etc.

I am using an original SBLive! card to capture via the SPDIF input. However I noticed that the recording level slider in the mixer panel affects the volume of the capture. Surely if it's a digital capture you should have no control over the volume of it? Which makes me think that that is the problem and that I am not capturing a valid digital signal but rather just a PCM audio stream that's converted via DAC back to a digital stream (A DAC in between is not what we want right?).

I only have a button in the mixer panel to select digital output only not a button to select digital input only so there is where I think the problem lies. What soundcard do you use?
Confused.

[oddball]

Yup! It's definitely the way the SBLive! is capturing the audio. I opened a working ac3 file in Cooledit by renaming it to .pcm and it looks and sounds totally different. A true ac3 raw file opened in Cooledit has no wavform just a big greenness and sounds like white noise. The capture on the otherhand does have a waveform and has an electronic patter patter type sound. It's capturing as some kinda PCM rather than a raw digital stream or something like that.

Off to the Creative message boards I go! ;)

[ZYron]

Hi oddball,

you are right .. you need a Card which can record Digital audio bit accurate! You can get some info about SB Live on http://grassomusic.de/english/rauschen.htm#phase ... looks not very promising ;(

Hopefully some people can name a few Card´s which can handle this ... I use a RME DiGI 96/PST.

Btw. found a faster way to convert the recorded Wave back to real AC3.

Save as WAV 16 Bit 48000Hz Stereo and use Besplit ->

BeSplit -core( -input live.wav -prefix d:\ -type ddwav -fix )

CYa ZYron

[sebus]

You are all wrong here. You are only talking about Digital sound capture. Digital sound is NOT the same what Dolby Digital AC3 (surround 5.1)

It makes TOTALLY no difference if we talk about sound coming from DVD player or LD player with RF Demodulator. It is all the same (as I said the RF Dem chnges the Pioneer propriety signal into a standard DD AC3)

So far there is NOTHING that can capture AC3 in full 5.1 surround.

Regards

sebus

[ZYron]

Hi sebus,

as i told before i connect my DVD Player via the Digital-Coaxial-Output with my Soundcard (RME DiGI 96/PST) and record the signal in Cooledit. Of course the DVD in the Player was AC3 encoded. My Amplifier connected via the Digital-Optical-Output of the DVD-Player indicated that. After recording I play the signal back in Cooledit and connected my Soundcard to my Amplifier and again it indicate that the signal is Dolby-Digital. Saving this signal to WAV and use Besplit to get a nice AC3 file !

I made that Test to find a way to help oddball... and it works, belief me or not, the problem is to get a Soundcard that samples bit accurate!

CYa ZYron

[sebus]

I will certainly give it a go.
Sounds like it could work (my apologies for jumping on you)

Regards

sebus

[crimazine]

heh heh "look before you jump!"

[crimazine]

ZYron, we are trying to capture with a Hercules Gamesurround Fortissimo 2 via the SPDIF Optical Input port. Starting a new file in Cooledit at 48000hz 16bit Stereo, when I hit record it records a discouraging STEREO stream. Is the card converting the digital signal to analog before letting cooledit record it? Any ideas would be greatly appreciated.

- crimazine

[oddball]

Sounds like the same issue I have. The sound you should get is a continuous white noise. If you are getting a static noise interspersed with short gaps it's just recording the digital signal a a PCM stream doing DAC (Digital to analog conversion). If you can control the volume level it's a pretty good indicator. Digital will be once solid block in Cooledit with no peaks and troughs as such.

[crimazine]

So this Hercules Fortissimo 2 card is not unlike the SB-Live in that its impossible? I read in the AC3 faq in this forum:

__Proven & Recommended Sound Cards for SPDIF pass through->

Audio Excel-Theater Excel-$19 USD
Hercules Fortissimo I & II-$45 USD <- the card im using :)
Hercules Game Theater XP- $110 USD
Terratec DMX XFire 1024-$58 USD
Philips Acoustic Edge - $??
M-Audio Dio 24/96 - $??

pass through doesnt necessarilly mean capturability?

- crimazine

[oddball]

No unfortunately. Pass thru just means it will pass the AC3 output from a DVD to the SPDIF out.

[crimazine]

damn ... well looks like i've reached a conclusion for this one ... no surround for this project.

- crimazine

[thankam]

Hai,
Any one have idea about DTS or Wav 5.1 files to DVD-/+R burning? or backup? (Re-Open)