Extract ARC+SREP on the fly

[Razor12911]

Yep. I think.

[danswano]

like what? an x64 version of srep/arc maybe?

[Razor12911]

There is a srep64 but I don't know whether it works with isdone 0.6 but you can et up thread and compression memory using freearc.

[danswano]

is it possible via command line?

[Razor12911]

yep,

-mt# - number of cpu threads
-lc# - compression memory usage

[danswano]

Hello dear Razor,
i've been testing since yesterday and i'm comparing my tests to an another already compressed file i have but the problem i don't know what values used to compress it.
I've unpacked it and re-compressed it, the original size is 4.05GB and mine after using the precomp command you gave me got 4.41GB.

Do you know what might be used on this file to get such lower size? with precomp or without it no problem.

if you have anything to add to the command to make an extreme smaller size please tell me.

Thank you

[Razor12911]

hmm, try precomo038, method arc-pcf-srep-arc.

try this one:
arc (-m0)
precomp (-slow)
srep (-m3f)
arc (-msrep+delta+rep+lzma:a1:mfbt4:d158m:fb273:mc1000:l c8)

[pakrat2k2]

also remember that you arcive files/folders with zero compression.
then precomp them > end up with much bigger file
then srep the result from precomp
finnaly compress the srep result with highest setting you want with freearc.

not an all in one shot deal, takes multiple steps to achieve final result.

[Razor12911]

Originally Posted by pakrat2k2

also remember that you arcive files/folders with zero compression.
then precomp them > end up with much bigger file
then srep the result from precomp
finnaly compress the srep result with highest setting you want with freearc.

not an all in one shot deal, takes multiple steps to achieve final result.

yea, that too. plus, keep an eye on the precomp file. it must be bigger, much bigger than the size of the original data.

[danswano]

Can you modify my command please, i'm such a noob in compression world.

arc a -ep1 -r -w -hpPASSWORD --HeadersPassword=123 data.arc "C:\Data\*" -mprecomp:t-jnf:zl31,34,39,44,55,64,67,68,73,74,75,84,85,94,97 ,99:d0+srep+exe+delta+lzma:a1:mfbt4:d158m:fb273:mc 1000:lc8

[danswano]

I forgot to mention that the original small file (4.05GB) Compressed using one step cause the files are directly inside the arc not an srep file.

[Razor12911]

was the original file precomp-ed?

[danswano]

I'm not sure because i'm not the file author.
If you can please provide a code for repacking with precomp and without it and i will test and reply back to you.

[Razor12911]

Testing files sometimes is a waste of time.

To find out what method was used click here

[danswano]

I wish i can do that but the author encrypted his work with password. :/