On Apr 25 at 1:13pm, Whelan, Paul wrote:
Does anyone know how to rip tracks off an iso image?
I thought I'd be clever and just dd one of my new cd's to my hard drive
for later ripping/encoding of the tracks.

Short answer:

You can't do that. The "image" you extracted with dd is useless and can be deleted. To extract audio, you need to use CD Paranoia on the disc directly.

   Long answer:

"ISO image" is short for "ISO-9660 filesystem image". ISO-9660 was the original industry standard for *data* CDs. It defines things like file name format, directory structure, block structure, and layout on disc. It has nothing to do with audio CDs.

Standard audio CDs -- those used for regular consumer music -- are in a format called CDDA (Compact Disc Digital Audio). CDDA is also called "Red Book audio". CDDA contains nothing like an ISO-9660 filesystem structure. CDDA discs contain from 1 to 99 tracks. Each track contains a stream of digital audio. There's a TOC (Table Of Contents) which allows CDDA players to find the tracks, and some other magic metadata, too.

While I've seen software which allowed you to extract a "raw image" of a CDDA disc, this isn't an ISO image. I'm not even sure there's any kind of standard for storing a "raw image" of an audio CD.

I *am* sure that one cannot use "dd" to extract the contents of a CDDA disc. The "dd" command, like most everything in *nix, assumes a file is a single stream of data, with no "forks" or other special "metadata". CDDA discs do not fit into this paradigm.

This is why cdparanoia (CDP) exists in the first place. First and foremost, CDP reads CDDA from a disc and dumps it into files. One doesn't use "dd" to rip an audio disc; one uses CDP. CDP additionally performs a lot of tracks to detect and recover from read errors. As noted above, CDDA is an audio *stream*. It isn't block-based like a hard disk is. So error detection and correction is a lot more complicated then one might expect.

Using "dd" to extract an ISO-9660 filesystem image isn't really a good idea, either. I'm a bit fuzzy on the details, but suffice it to say that it doesn't always work. Using special-purpose tools such as "readcd" is a better idea.

   Hope this helps,

--
Ben <[EMAIL PROTECTED]>
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