How to extract each audio channel in a DAT file (from VCD)?

[coxanhvn]

Just wondering if I'm even able to do that? Thanks,

[AlanHK]

You could try just open the file in Audacity, the 1.3 series with ffmpeg filters.

If that doesn't work, first use VCDGear with "DAT-> MPEG".
Then Audacity on the MPEG.

VCDs use MP2 stereo audio.

In Audacity you can split the stereo to 2 mono tracks.

[coxanhvn]

Thanks Alan, I tried as what you suggested but nothing worked; however, I found Mp3AudioEditor and it did the job for me. So anyway, my next questions are:

1. How different between MP2 and MP3 'cause they both can contain 2 channel audio right?
2. Which software can extract the audio (MP2) and video (???) in a DAT file?
3. How many audio channels can an MP2 or MP3 contain 'cause for the same file that I just did (which has 2 channels), i opened it in PowerDVD and it showed up 3 (L, R and Both), and in another program it gave me 4 (L, R, L Stereo and R Stereo)?

Thanks in advance,

[davexnet]

See this:
http://en.wikipedia.org/wiki/Video_CD#Audio

[AlanHK]

The software I mentioned works for me.

Maybe TMPGEnc can read DAT files.
If so use Tools/Demultiplex to get the audio as an MP2.


See the "VCD: link above: https://www.videohelp.com/vcd
Audio:
44100 Hz
224 kbit/sec MPEG-1 Layer2

MP2 and MP3 can only be mono or stereo, L+R.
Any other channels are being faked by the software.

"L stereo" means it duplicates the Left channel and puts it to both speakers.
That's done because some VCDs use the stereo audio to have two mono tracks in different languages, as VCDs don't support multiple soundtracks. You use that if you hear English and Chinese (for example) at the same time.

[jman98]

Where are these VCDs from? India and Pakistan use some non-standard copy protection stuff that might prevent VCDGear from working. In general other countries don't use this and VCDGear should work to get the audio and video out of the disc. I use MPEGVCR for demuxing once I do that but as AlanHK points out TMPGenc should work for demuxing.

[Cornucopia]

Let's get the facts straight.

1st - MP2 & MP3 Both have 5.1 & 7.1 Implementations, though rare. I have copies of the tools that'll do this for both. Heck, it's even in the SVCD spec to allow 4 mono streams, 2 stereo streams, or 1 multichannel stream (all MP2).
2nd - Under the hood, MP3 is alot more complicated than MP2, that's why it's much more efficient a compression. They're (usually) backwards compatible, so if you have something that'll play/edit MP3's, it's very likely to play/edit MP2's and even the old & rarely-used MP1's (these usually came from DCC's).
3rd - "L, R, & Both" is not 3 channels, it's 2. You have the option of listening to only L or only R or both (or neither). Same with that "4ch" suggestion.

Here's the general steps one would take:
1. Ripping from Disc to HD & removing M2F2 sector headers (important!)
2. Demuxing from System/Program stream to Elementary stream
3. Decoding & opening in editor/player

For #1, I'd use either ISOBuster, VCDEasy, or VCDGear as they all thoroughly understand VCDs and can correctly extract the file while also removing the CDXA Mode2Form2 Sector Header info, etc. Otherwise, you've got extra crap in your file that'll make it either have trouble being read in #2 or #3, or it'll be interpreted as an ERROR, or it'll be processed and sound like some additional static.

For #2, I'd use MPEGVCR, TMPGEnc, Imago, on one of many other MPEG Muxer/Demuxers.

For #3, as mentioned before, Audacity, CoolEdit, or any other editor that supports MP2 (and as I said before, if it supports MP3, it probably also supports MP2).

Scott

[AlanHK]

Let's get the facts straight.

1st - MP2 & MP3 Both have 5.1 & 7.1 Implementations, though rare.

On paper. Never seen in the wild.
In particular, never seen on any VCD (note title of this thread).

The VCDs on sale (and I had hundreds) all only had one stereo track; and some used the trick of one language in left and a different one in right. Never saw any with more tracks.

[Cornucopia]

I've got a test disc I might post. It's got Multi-channel, MP3 & AC3 as audio on a VCD (as well as another disc which has Widescreen, or one with SVCD-in-VCD and VCD-in-SVCD). Some sections work in some players, other sections in others, etc. None work in all players, though. That's what you get for going off-spec.

What I was stating was against the statement that "MP2 and MP3 can only be mono or stereo", but I agree that "VCD audio can only be mono or stereo". Small difference, but one just the same.

Scott

[jman98]

Hey Scott - if you want to post your test disc I'd be interested. Like AlanHK I've also never seen this in the wild and I do buy VCDs at times. For the curious as to why I sometimes buy VCDs, some foreign films were only released on VCD and never on any other format. Sometimes I buy them because they can be really cheap.