Recover audio CD after safecopy

I have an audio CD (burnt a few years ago) that I want to rip (with K3B or other) to flac. K3B was unable to complete and I realized the CD was damaged. I managed to recover the data with safecopy and the --stage-1-3 arguments. From the output (see below) it seems that the data was properly recovered. However, I expected to be able to mount the file and take it from there. Unfortunately it doesn't seem to be the case: $ sudo mount -o loop -t iso9660 diskimage /media/cdrom1/ mount: block device /mnt/data/Bureau/diskimage is write-protected, mounting read-only mount: wrong fs type, bad option, bad superblock on /dev/loop1, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so dmesg doesn't show much useful output: $ dmesg | tail ISOFS: Unable to identify CD-ROM format. Indeed it seems to be in an unrecognized format: $ file diskimage diskimage: data Unsurprisingly, renaming the file to .iso, .raw, .img or .bin made no difference. Some people on the Internet recommend using ccd2iso but it fails as well (Unrecognized sector mode (0) at sector 0!). How can I proceed to extract the audio from this raw data dump? Here is the output from safecopy. The stage3.badblocks is empty. $ safecopy /dev/sr0 diskimage --stage1 Low level device calls enabled mode: 2 Reported hw blocksize: 4096 CDROM audio - low level access: drive reset, raw read CDROM low level disk size: 784954128 CDROM low level block size: 2352 Reported low level blocksize: 2352 File size: 784954128 Blocksize: 2352 Fault skip blocksize: 78493296 Resolution: 78493296 Min read attempts: 1 Head moves on read error: 0 Badblocks output: stage1.badblocks Marker string: BaDbLoCk Starting block: 0 Source: /dev/sr0 Destination: diskimage ......................................... ......................................... ......................................... ......................................... ......................................... ......................................... ................................(+669325104){X }(+78493296) ................(+37135728){X}(+78493296) Done! Recovered bad blocks: 0 Unrecoverable bad blocks (bytes): 2 (156986592) Blocks (bytes) copied: 333739 (784954128) xavier@marvin:~/Bureau$ safecopy /dev/sr0 diskimage --stage2 Low level device calls enabled mode: 2 Reported hw blocksize: 4096 CDROM audio - low level access: drive reset, raw read CDROM low level disk size: 784954128 CDROM low level block size: 2352 Reported low level blocksize: 2352 File size: 784954128 Blocksize: 2352 Fault skip blocksize: 301056 Resolution: 2352 Min read attempts: 1 Head moves on read error: 0 Incremental mode file: stage1.badblocks Incremental mode blocksize: 2352 Badblocks output: stage2.badblocks Starting block: 0 Source: /dev/sr0 Destination: diskimage Current destination size: 863447424 ........................(+726878544){X <<<<<<<}(+2352) .....(+10090080){X<<<<<<<}(+2352) ..... 8-( 95% Done! Recovered bad blocks: 0 Unrecoverable bad blocks (bytes): 2 (4704) Blocks (bytes) copied: 317950 (747818400) $ safecopy /dev/sr0 diskimage --stage3 Low level device calls enabled mode: 2 Reported hw blocksize: 4096 CDROM audio - low level access: drive reset, raw read CDROM low level disk size: 784954128 CDROM low level block size: 2352 Reported low level blocksize: 2352 File size: 784954128 Blocksize: 2352 Fault skip blocksize: 2352 Resolution: 2352 Min read attempts: 4 Head moves on read error: 1 Incremental mode file: stage2.badblocks Incremental mode blocksize: 2352 Badblocks output: stage3.badblocks Starting block: 0 Source: /dev/sr0 Destination: diskimage Current destination size: 863447424 . 8-( 93% Done! Recovered bad blocks: 0 Unrecoverable bad blocks (bytes): 0 (0) Blocks (bytes) copied: 313339 (736973328)