[gentoo-user] Re: Damaged CD medium

[Grant Edwards <grant.b.edwards@gmail.com>]

On 2015-03-13, Mick <michaelkintzios@gmail.com> wrote:
> Hi All,
>
> I was given a CD with some pictures, but I am not able to mount it.  This is 
> what dmesg reveals:

Here's what I recommend.

 1) Use ddrescue to read as many data blocks as you can off the CD.

      http://www.gnu.org/software/ddrescue/
 
    ddrescue will retry failing blocks and then skip over them.  You
    can rerun ddrescue to try to fill in missing blocks.  dd or cat
    will generally just stop when it hits the first bad block.

    I would do something like:

     a) Run several passes of ddrescue using a few different optical
        drives.

     b) Polish the CD.

     c) Repeat until you stop getting new data off the CD.     
    
    
 2) Use something like photorec to try to scavange any reconizable
    JPEGs (or other file types as desired) from the data image file
    you created with ddrescue.

      http://www.cgsecurity.org/wiki/PhotoRec
      
IIRC, there are ebuilds for ddrescue, photorec, and testdisk.

-- 
Grant Edwards               grant.b.edwards        Yow! I like the way ONLY
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