Tuesday 29 April 2008

Monday 21 April 2008

JPEG 2000 vs H.264 -- FIGHT!

here is the Video Communication project from our dear Vittorio Picco and fresh Giacomo Campieri from the telecomunication team!

They thoroughly analized two very popular compression format, jpeg2000 and h264, providing several images as example.

check it out!
http://www.scribd.com/doc/2581731/H264AVC-intra-coding-and-JPEG-2000-comparison?ga_uploads=1

Thursday 17 April 2008

Presenting some slides

Right in the middle of our exams, here we provide you the mithical slides we used for presenting our works from previous times!

About Computer Systems Security
http://www.scribd.com/doc/2563498/slides-OpenSSL-User-Manual-and-Data-Format
http://www.scribd.com/doc/2563466/slides-Block-Cipher-Modes-of-Operation-and-CMAC-for-Authentication
http://www.scribd.com/doc/2563436/slides-Authenticated-Encryption-GCM-CCM

and one we forgot to upload about the famous division algorithm
http://www.scribd.com/doc/2563434/slides-MicroprocessorBased-Systems-4832bit-division-algorithm-

all in pdf so you can read them anywhere without problems ;)
more to come in the following weeks
bye for now!

Friday 4 April 2008

20s boot

Finally i had some time to play with Gentoo on the Toshiba M200 i bought from the USA.
this time i wanted to tune every possible bit of the kernel in order to obtain a quickest boot as possible! i seem to have managed to fullfill my plans!

here is a couple of hints i can share (some of them might a little bit risky)
  • first of all, i tried to make the kernel as small as possible, totally moduable a very little built in! i believe there's now only the pci, ide, generic x86 istructions and the root fs support, while all the rest gets loaded at boot.
  • to know which modules are absolutely necessary, take a look at the udev printing! move all the modules it loads to /etc/modules.autoload/kernel-2.6 and then disable the RC_COLDPLUG variable in /etc/conf.d/rc.
  • while in /etc/conf.d/rc you can also set the PARALLEL stuff in order to speed up services starting, but it's not very effective
  • i shrunk the root partition so that the checkroot service will take much less time for controlling the filesystem. While here i also modded the init script to hdparm the drive before performing the scan.
Well that's more or less what i tried to do, and everything seems to work fine!
next target: create an initramfs to load the modules for an even faster boot :)



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If you wish to get in touch with me write at projectsymphony@gmail.com