dvdisaster Version 0.66  To the Internet version
Contents

Overview
Examples and screen shots
·Scanning media for errors
·Creating error correction data
-as a file
-within the image
·Reading defective media
·Recovering media images
·Getting information about images and error correction data
·Configuration
·Command syntax
Download
Questions and Answers
Background information
Imprint

Augmenting the image with error correction data

Augmenting images with error correction data is currently only supported at the command line. The respective functions will be integrated into the graphical user interface in dvdisaster version 0.70.

Create an image of the data to be protected.

Use your favourite CD/DVD writing software to select data files and create an ISO or UDF image from them. Using other image types may lead to data loss!

Append the error correction data to the image.

This requires the following parameters (defaults are given in parenthesis):
-c/ --create Create the error correction data
-m / --method  Select the error correction method
-n / --redundancy maximum medium size in sectors (size of smallest possible medium)

When you have created the image "image.iso" using the CD/DVD writing software, enter:

user@linux> dvdisaster -c -mRS02 -i image.iso
dvdisaster-0.66 Copyright 2004-2006 Carsten Gnoerlich.
[... remainder of the GPL announcement ...]

Opening /dvd/image.iso: 284234 medium sectors.

Appending image with Method RS02: 555M data, 143M ecc (52 roots; 25.6% redundancy)
Calculating sector checksums: 100%
Expanding image: 100%
Ecc generation: 100.0%
Image has been appended with error correction data.
New image size is 357818 sectors.

Write the image to the medium.

Use your CD/DVD writing software to transfer the augmented image to the medium.

Your writing software may not be compatible with the augmented image and destroy the error correction information. At least when using it the first time, perform the following check:

Re-read the image with dvdisaster after burning the medium:

-r/ --read Read
-d / --device  Drive selection (/dev/cdrom)
-i / --image Image file (medium.iso)

user@linux> dvdisaster -r -d/dev/hdc -i image-new.iso
dvdisaster-0.66 Copyright 2004-2006 Carsten Gnoerlich.
[... remainder of the GPL announcement ...]

Device: /dev/hdc,  ATAPI DVD+RW 8X4X12 B2K7
Medium: Data CD Mode 1, 357818 sectors, 1 layer(s)

Creating new image-new.iso image.
Waiting 5 seconds for drive to spin up...
Read position: 100.0% ( 6.3x)
All sectors successfully read.

Check the image:

-t/ --test Check the image
-i / --image Image file (medium.iso)

user@linux> dvdisaster -t -i image-new.iso
dvdisaster-0.66 Copyright 2004-2006 Carsten Gnörlich.
[... remainder of the GPL announcement ...]

dvd/new-image.iso: present, contains 357818 medium sectors.
- good image : all sectors present
- data md5sum : 4eca3615a88a11ba68466226295c4bcb

Error correction data: created by dvdisaster-0.66
- method : RS02, 52 roots, 25.6% redundancy.
- requires : dvdisaster-0.65 (good)
- data md5sum : 4eca3615a88a11ba68466226295c4bcb (good)
- crc md5sum : 9776489c12e12cbabfe5145da4f6ae66 (good)
- ecc md5sum : e975aed39c962eeabedd9d6cbdbfc45e (good)

Copyright 2004-2006 Carsten Gnörlich.
Verbatim copying and distribution of this entire article is permitted in any medium, provided this notice is preserved.