Add parity data to ISO images in Build mode

[geno888]

Hi LUK

 

I'd like to request for a new feature to be implemented in ImgBurn.

 

I have no idea if it is easy to do, but I think that it will be a very interesting and useful feature

 

Recently I started to use a software named DVDisaster. It is an opensource software to modify ISO files adding parity data to the image, to increase security and to increase the probability to recover data if the disc becomes damaged in some way. It basically uses all the remaining free space available to completely fill a DVD to the brim, adding parity data to the ISO.

 

The procedure I use at the moment is the following: First I create an ISO file with ImgBurn (having care to leave enough free space to contain parity data, usually around 800 MB), and then I run DVDisaster to add parity data.

 

I wonder if it is possible to make ImgBurn directly create an ISO file in build mode containing parity data, so I can create an ISO directly in build mode without being forced to use an external software. In fact, even if DVDisaster is an excellent software, the entire process is rather time consuming if you must create many ISO files.

 

What I'd like to have is the possibility to select in options if ImgBurn will create an ISO image regularly (i.e. in the way it already do) or adding parity data.

 

According to the DVDisaster software, at least 20% of the disc space must be dedicated to parity data to ensure a reliable disc recovery, but I think that the user should be able to select manually how much parity data insert in the file, so it will be useful to have in options a field to put the amount of parity data to be included in the image (this information will be necessary for ImgBurn to exactly calculate which media must be used to contain all the data when you progressively add data to the build window). I think that the user should be able to choose an amount variable from 10% to 50% (more than 50% is a nonsense in my opinion, and actually 50% could be an excessive amount too, maybe between 10 and 35 or 40 is sufficient to ensure a sufficient protection against data loss).

 

I'd like to add also that actually I have no idea what are exactly these "parity data" added by DVDisaster to the ISO file, sorry

 

I hope that I was able to explain enough clearly what I meant (sorry for my poor English )

 

Do you think that this feature could be implemented in future versions of ImgBurn?

 

TIA

 

geno

[_Greg_]

I also wouldn't mind seeing a feature like this. It is probably not possible in many cases to generate the parity data in real-time during the burning process, but the single build-adding-parity process described by geno would be quite useful.

 

In cases where sufficient disc capacity is available, it may be simplest to calculate RS codes on a frame-by-frame (32KB) basis and then span each byte of the codes across different frames (so that loss of a frame minimizes the loss of ECC data for another particular frame). This would probably work well for discs with scratches or scuffs not covering the majority of the surface. Burned discs tend to go bad from the outside-in, but some go bad from other areas first. For that issue, the user could opt to specify a general preference for where the ECC data goes into the ISO relative to the data. The ECC data could be ordered different ways from sequentially (to match the order of the corresponding frames) to random (to attempt to maximize the probability that at least some ECC data will be readable).

 

Of course, this could all be made a hell of a lot more efficient and useful if standard drive firmware weren't rigged to disallow reading of data from bad frames on DVDs.

Edited November 17, 2008 by _Greg_