54 lines
2.9 KiB
Markdown
54 lines
2.9 KiB
Markdown
# dvdisaster provides additional ECC protection for optical media
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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.
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This version of dvdisaster supports the following platforms:
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Linux, FreeBSD, NetBSD on x86, PowerPC, Sparc, and Windows.
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Three protection codecs are supported, they're quickly detailed below. Please see the documentation/manual.pdf for more information about these, and everything else.
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# The codecs
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## RS01
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RS01 creates error correction files which are stored separately from the image they
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belong to. The artefact is an **ecc** file, which must be stored on another media than the one we're protecting.
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## RS02
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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
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information is not required.
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## RS03
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RS03 is a further development of RS01 and RS02. It can create both error correction files and
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augmented images, with the following added features:
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- RS03 can distribute work over multiple processor cores and is therefore much faster than
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RS01/RS02 on modern hardware.
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- RS03 error correction files are - contrary to RS01 - robust against damage. This should
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not delude you into careless handling of your error correction files though - the disadvan-
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tages of reading at the filesystem level are still valid.
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- RS03 augmented images do not require so-called master blocks holding important in-
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formation. This makes RS03 a bit more robust, but also more restrictive: The augmented
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image must completely fill the medium now while the size of augmented images can be
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freely chosen in RS02.
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The changes for parallel computation and higher robustness make RS03 a bit less space efficient,
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e.g. RS03 error correction data has slighly less error correction capacity than its RS01/RS02
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counterparts on images with equal size.
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# Unofficial version
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The last upstream version is dated 2017, and the official website is down.
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The original README has been left untouched in this repository.
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This version is built on top of the latest upstream version, with the following notable enhancements:
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- Most Debian patches have been applied (The Debian version source code can be found [here](https://sources.debian.org/src/dvdisaster/))
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- Windows build added back (was dropped upstream a few versions before the last one)
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- A Linux CLI-only version can now be compiled, without depending on gtk
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- Regression tests confirmed working on Linux64 (normal and CLI-only), Windows32 and Windows64
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- Added pre-defined sizes for BD-R Triple Layer (100GB), BD-R Quadruple Layer (128GB)
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# Screenshots
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(todo)
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