#15 Double file detector

[Anonymous]

just a nice feature i was thinking of to improve
compression.

Double file remover.

As every compressed file is crc 32 checked, the
compressor could keep a list of file sizes and crc32
values in memmory.
For every "new" file to be compressed it would check
the size against this list.

If any previes files is on the list with the same size, a
crc32 check should made onthe new (yet to be
compressed) file to se if its is inded the same file
if it is a pointer to the allreade compressed double file
should be there insted og compressed data.
if not compression continues as normal.

This would reduce size when comperssion af a lot of the
samme programs but in different langue. (e.g. the XP
sp1) as there are many files that are 100% identical. but
lies to far away for the dictionary size to use the
repeatable pattern.

[Igor Pavlov]

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user_id=65083

Do these identical files has different names in XP sp1?

If names are the same, files will be compressed together
in solid mode. So if dictionary size will be larger than
file size, compressing will be effective.

[Nobody/Anonymous]

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names are the same and only a few filere are actual different
(checked by comparing .sfv files )

but the compresed file is nowhere near 50%.

and yes there is many cabs files (allready compressed) both
most of them (if not all) are identical

[Nobody/Anonymous]

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This feature if implemented can allow to have multiple (incremental)
backups of the same directory in the same archive just adding the files
which have changed (possibly only parts of them which have changed:
see the program diff)
CD

[Nobody/Anonymous]

Logged In: NO

This feature if implemented can allow to have multiple (incremental)
backups of the same directory in the same archive just adding the files
which have changed (possibly only parts of them which have changed:
see the program diff)
CD