Comment 0 for bug 391193

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Thomas Guyot-Sionnest (dermoth) wrote :

Binary package hint: brasero

This bud apply to the brasero application in Ubuntu Jaunty

When creating an audio disc copy (probably apply to any disks though) braserro uses cdrdao with the --read-raw
parameter. As stated in the manual, --read-raw reads data and P-W subchannels uncorrected, which mean that any correctable errors is copied as-it to the image file.

If the CD burner supports writing R-W subchannel data, the resulting CD therefore contains any read-errors (that are normally corrected) burnt in the copied cd.

This usually works as cd players can still use the error correction data to correct there errors, however these CDs are weaker since the have errors burnt-in and may not work on some poor-quality players.

For instance I created two copies from a CD and none of them would work on one of my cd players... for testing I re-copied the "broken" cd using cdrdao with the "--read-subchan rw" option instead and the resulting cd was perfectly readable on all my players.

The "--read-subchan rw" option makes a similar images but creates corrected data and R-W subchannel data. This results in a better quality reproduction without any subchannel data loss (ISRC, CD-TEXT, etc.). The --read-raw option is generally used when working with intentionally damaged disks bundled with copy protection systems.