79 lines
4.7 KiB
Markdown
79 lines
4.7 KiB
Markdown
# dvdisaster provides additional ECC protection for optical media
|
|
|
|
It can loosely be compared to *par2* files, but the protection works at the *iso* level instead of working at the file level. This way, even if metadata from the optical media filesystem is damaged, dvdisaster can still work flawlessly.
|
|
|
|
This version of dvdisaster supports the following platforms:
|
|
Linux, FreeBSD, NetBSD on x86, PowerPC, Sparc, and Windows.
|
|
|
|
Three protection codecs are supported, they're quickly detailed below. Please see the documentation/manual.pdf for more information about these, and everything else.
|
|
|
|
# The codecs
|
|
|
|
## RS01
|
|
|
|
RS01 creates error correction files which are stored separately from the image they
|
|
belong to. The artefact is an **ecc** file, which must be stored on another media than the one we're protecting.
|
|
|
|
## RS02
|
|
|
|
RS02 creates error correction data which is added to the medium to protect, we call this *augmenting* the image we're protecting. Damaged sectors in the error correction information reduce the data recovering capacity, but do not make recovery impossible - a second medium for keeping or protecting the error correction
|
|
information is not required.
|
|
|
|
## RS03
|
|
|
|
RS03 is a further development of RS01 and RS02. It can create both error correction files and
|
|
augmented images, with the following added features:
|
|
|
|
- RS03 can distribute work over multiple processor cores and is therefore much faster than
|
|
RS01/RS02 on modern hardware.
|
|
- RS03 error correction files are - contrary to RS01 - robust against damage. This should
|
|
not delude you into careless handling of your error correction files though - the disadvantages
|
|
of reading at the filesystem level are still valid.
|
|
- RS03 augmented images do not require so-called master blocks holding important in-
|
|
formation. This makes RS03 a bit more robust, but also more restrictive: The augmented
|
|
image must completely fill the medium now while the size of augmented images can be
|
|
freely chosen in RS02.
|
|
The changes for parallel computation and higher robustness make RS03 a bit less space efficient,
|
|
e.g. RS03 error correction data has slighly less error correction capacity than its RS01/RS02
|
|
counterparts on images with equal size.
|
|
|
|
# Unofficial version
|
|
|
|
The last upstream version by Carsten Gnörlich is dated 2017, and could be found on the [official](https://web.archive.org/web/20180428070843/http://dvdisaster.net/en/index.html) [website](https://web.archive.org/web/20180509154525/http://dvdisaster.org/en/index.html) which is [now](http://www.dvdisaster.net) [down](http://www.dvdisaster.org). The original source code [repository](https://sourceforge.net/projects/dvdisaster/files/dvdisaster) doesn't have it, but [Debian sources](https://sources.debian.org/src/dvdisaster/) does, thanks to the maintainer there.
|
|
The original README has been left untouched in this repository.
|
|
This version is built on top of the latest upstream version, with the following notable enhancements:
|
|
|
|
- Most Debian patches have been applied, those specific to Debian have been omitted
|
|
- Windows build supported again, it was dropped upstream a few versions back
|
|
- A Linux CLI-only version is now supported, without depending on gtk (`CLI_ONLY=1 ./configure && make clean && make -j4`)
|
|
- Regression tests confirmed working on Linux64 (normal and CLI-only), Windows32 and Windows64
|
|
- Added pre-defined sizes for BD-R Triple Layer (100GB), BD-R Quadruple Layer (128GB)
|
|
|
|
# Rationale
|
|
|
|
Even if the optical media era is sunsetting now, and has been for a few years, it's still of some value for off-site backups. In any case, we still have media in our hands that we want to be able to repair, should it be damaged, during the next years/decades. Repairing is actually pretty much the very reason of dvdisaster existence (as long as parity data has been added, of course).
|
|
The idea of this unofficial version is to ensure dvdisaster doesn't get hard to find, use or compile, should upstream development never resume (we hope it does!).
|
|
This is also why precompiled Windows binaries and a precompiled static CLI-only Linux version are available here.
|
|
|
|
# Compiling
|
|
|
|
See the INSTALL file
|
|
|
|
# Screenshots
|
|
|
|
### Scanning a damaged CD under Windows
|
|
|
|
|
|
|
|
### Scanning a healthy BD-R (single layer) with Linux GUI
|
|
|
|
|
|
|
|
### Creating an RS03 error correction file with Linux GUI
|
|
|
|
|
|
|
|
### Verifying a BD-R image with Linux GUI
|
|
|
|
|