I have drawn a vast amount of knowledge from this remarkable site. It was therefore justice that I should myself provide with my humble contribution. (I have to say that my computer culture is rather limited; however the trick described below actually does work,. . . even if I do not know exactly why).
I was in the situation of someone who had to backup a video DVD in spite of the damages to the surface of the DVD itself. It was a long film (circa 2.30 hours, in which only a few seconds were flawed). Albeit minute, the error was sufficient to prevent DVD-Shrink from encoding the DVD. The error message was : "Cyclic redundancy check - Blah blah blah". (Immense irritation on my side).
Then I recalled the existence of some backup software that process data in "raw" mode. In that case the software disregards the nature of the data to backup; in other words it does not try to "understand" the content of these data. When there are errors, these are servilely copied. One of these software is Alcohol 120%, a soft that I did not use on that occasion (dunno why. . . .). The
other soft that I know is "BlindWrite 6" (hereafter "BW"). BW allows you to extract an image from a damaged DVD. What kind of image will you want? You can have an "BW6 image", but it is probably complicated to mount. So, instead, I chose an "ISO" image, this format seeming more generic. Then BW extracted the image. The extraction was a relatively slow process, probably because BW tried to ignore (or to solve?) reading errors. It has dawned to me that the reading process was all the slower that the damages to the disk were numerous.
When the ISO image is extracted, you can mount it. For that purpose, I used DaemonTools (a free software); but I am sure that other tools might do this job equally well (including Alcohol).
From this mounted image, DVD-Shrink easily encoded DVD files. Granted, the (few) problematic seconds of the film were indeed lost. Granted, the film was jittering a little at times. But all the other parts of the film had been safely backuped. At the end of the day, what I got was almost identical to a backup obtained from a brand new (undamaged) DVD.
I hope these lines will be useful to some of your members. (But I must stress that it is probably wiser not to let the toddlers play with your DVD:s!)
[To be thorough, I think I ought to mention the availability of software tools the purpose (essential or ancillary) of which is to rescue data from a damaged DVD or CD. I have drawn up a list of such tools but have not tested any of them: these are:
- CD Recovery
- DVD Data Rescue
- DVD Fab Decrypter
- IsoBuster - Magic Iso
- Roadkill-Unstoppable-Copier, and
- SuperCopier].
Thank you, again, for the intellectual wealth of your site.