HydrogenAudio

Digital Audio/Video => General A/V => Topic started by: skexu on 2011-02-21 18:01:42

Title: Demuxing audio out of dvd/vcd
Post by: skexu on 2011-02-21 18:01:42
So, I have some DVD concerts and I've tried in past a few programs to extract audio from them and convert to MP3, but recently I've started to more CARE about quality, and now I know transcoding isn't really good. IIRC Easy DVD Extractor has only option to extract mp3/wav/ac3.

Most DVDs have MP2 audio, and I can actually play MP2 on computer (portability not really interests me in this case). Can you recommend me a program to extract audio stream out of DVD without conversion (losing quality)?

A option for VCD (MP1) would be nice to see but I actually don't need it lol (just testing).
Title: Demuxing audio out of dvd/vcd
Post by: DVDdoug on 2011-02-22 20:28:50
Quote
Most DVDs have MP2 audio..
Actually, most commercial DVDs, have AC3 audio (multiplexed into the MPEG-2 stream).    I don't think I've ever seen MP2 audio on a DVD.

PAL players (most of the world) are required to play MP-2 audio, but NTSC (American) DVD players are not.  So, all NTSC DVDs are required to have an AC3 or LPCM track.  MP-2 (and DTS, etc) are optional.  I'd guess that 10% of my DVDs have LPCM audio (uncompressed).

If Eazy DVD Extractor can extract to WAV (and if WAV is acceptable for you) that should give you a "high quality" file that contais the same PCM data you get when you play the original file (and de-compresss on-the-fly).

A couple of other tools you can try:
VOB2MPG[/b][/u] (http://www.svcd2dvd.com/default.aspx)  (FREE!!!) can combine the VOB files to one-big MPEG-2 A/V file.  (It only works with un-encrypted DVDs.)

SUPER[/u] (http://www.erightsoft.com/SUPER.html) can be used extract the audio-only, and in the "stream mode", it won't transcode.

You can also look for a "demultiplexer" to separate the audio & video. 

Transcoding is something we'd all like to avoid, but it's not always that bad.  I usually transcode AC3 to  (high-quality) MP3, and I've never noticed any degradation (except that I can't get 5.1 digital surround  ).  Whenever I thought I heard an MP3 artifact, the same defect has been present on the original.

And, I usually edit the individual concert-tracks to fade-in and fade-out the crowd noise.  Editing requires decoding & re-coding anyway.
Title: Demuxing audio out of dvd/vcd
Post by: skexu on 2011-02-24 14:32:11
Thanks!.. I actually have only heard about the MP2 (I know it isn't related to mpeg-2 video) so it's my bad, I was just referring to others' words, I'd better further read about Ac3 format and if it's a big loss to convert to mp3.

If I somehow couldn't manage to get original audio stream then I'll post.
Title: Demuxing audio out of dvd/vcd
Post by: B7k on 2011-06-27 07:10:23
VLC can extract both the origonal video and audio no converting.