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no compression of a sector-by-sector backup: why ?

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Hi,

Can somebody explain to me why the full sector-by-sector backup isn't compressed? There is no difference between bytes read from a file, or bytes read from some not-in-use-part of a disk.  I understand that it is possible that the bytes from unused part of the disk are random, so hard to compress, but now Acronis doesnt even try to compress it.

I really need a sector by sector backup, including the 'unused' parts, since some software programs like to put their stupid DRM data there, but I really don't like the fact that these kind of backups are that big.

It's totally unnecessary that these backup files are that big.

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To all intents and purposes a sector by sector back up is a clone of a disk by another name. The difference being it is contained within a tib container and can be 'saved' anywhere that has the space.

So as information is less likely to be corrupted and so that on restore everything goes back as it was, compression is not possible.

Some software includes the empty secotrs and their placements as part of their anti pirating attempts, if the drive has been compressed then the expanding algorithm may not put exact sectors back in the exact place or starting at the exact addresses.

Colin B: 0 points.
Torsten Hoff: 10 points.

Compression is possible, but they choose not to implement it.

Which is kinda strange, since activating the sector-by-sector option ensures that to maximum amount of data has to be backup'ed; so compression would be most usefull with this option.

If you compress a sector by sector operation you will not as I stated always get back the exact structure that you started with.

Some disk formats wouldn't be able to cope with this. The safest option as True Image might be dealing with an OS it has no idea about is to copy everything exactly as it is.

That's simply wrong.

True Image uses lossless data compression, during a restore it gets back the exact same data it originally compressed during the backup. There is no technical reason why it can't apply this to a sector-by-sector backup.