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TrueDisc Error Correction for Disc Burning?
An anonymous reader asks: "Macintouch has a link to a new piece of software — TrueDisc — which claims to make data burned to record-able discs more reliable. More specifically it uses interleaved redundant cells to rebuild data should part of the disc be scratched. On the developer's blog they say they plan to create an open-source implementation of the TrueDisc system, now that it is not going to be included in the Blu-ray/HD-DVD standards. Have any of you used this software before, and what alternatives are already available?"
If you are backing up important data, having the disk go bad is only one issue. I always "duplicate the data"...one disc stays home, one goes to work. No other error correction scheme will work if my house burns down.
The cake is a pie
Music CD's already include error correction bytes embedded in each frame of data, so I assume this technology does the same sort of thing for data CD's/DVD's/bluray's/etc..
On music CD's, there's one error correction byte for every three bytes of data. That's a lot more space-efficient than just burning your data twice.....
Music CD's have piss poor error correction, by data standards. CD-ROM and DVD-ROM (which includes the video variant, since it's an application of DVD-ROM) have much more robust error correction. There is more error detection (and correction) per block on a CD-ROM (consequently, less for data) than on a music CD. Music CDs have the additional advantage of not needing to be precise; it can try to guess (interpolate) the missing data it runs into, or, at worse, skip (which may or may not be noticable). Can't do that with a spreadsheet.
Burning your data twice also has the advantage of being able to separate the copies (to different physical locations). Error correction technologies aren't going to help if you CDs and DVDs are roasted in a fire; the extra copy you made and put into storage elsewhere will still be safe.