Tech

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Get rid of undesired APK icon

Posted by zdravko on 16 Feb 2013 | Tagged as: Android, Tech

For almost a month now I am a proud owner of Google`s Nexus 4 smartphone. I had to switch from the stock Email client to K-9 Mail application. What really bugged me up was the dog-envelope icon K-9 developers had chosen. In my thinking it was not appropriate for an email client at all. So, I was looking for a way of how to replace that icon, and ultimately ended on APK Multi-Tool web site, which tool, among other things, may replace APK`s icon, and do it proper. Basically you have to do this:

1. Download and extract APK Multi-Tool in a folder of yours choice, and run its Setup script and follow the instruction;
2. Copy K-9.apk from your phone and put it under “place-apk-here-for-modding” sub-folder of the above location;
3. Run the Script script, and choose option one – Extract for K-9.apk (the extracted files shall go under “projects” sub-folder);
4. Go find them and replace the file icon.png in both “res\drawable” and “res\drawable-hdpi” sub-folders with a new icon;
5. Make sure your phone is connected in Camera mode to your PC`s USB port and all drivers have been installed;
6. Go back to the Script window and choose option 7 – Zip, Sign, Install. The modified APK will be sent to phone and installed.

NB! Make sure the original application is uninstalled in advance because APK Multi-Tool shall generate a different signature of the apk file and installation shall fail. You don’t have to do this again for any subsequent uploads, i.e. would you like to test some other icons as well.

Here is what my new K-9 Mail application`s icon looks like — ahh, much better:

CPU upgrade

Posted by zdravko on 18 Aug 2012 | Tagged as: Cool, Tech

I have been looking for a CPU upgrade for some time, but since my Mobo is quite old socket AM2+ I was quite limited in what I can get. The best option was AMD Phenom X6 1100T, which is running at stock 3300GHz speed, and also supports Turbo-core at 3700GHz. Going beyond that would have required that all Mobo, CPU and RAM change. So I decided to stay with my current set up and find out that 1100T AMD CPU.

All went well just until I realized that these CPU-s are end-of-life and very hard to find. Not a single one here in Bulgaria, not available in Amazon UK and Amazon DE, and some second hand offers in Amazon US. At that moment I started considering alternatives (as AMD 960T one). I got 965 Black Edition AMD 4-core but still I was looking for 1100T 6-core one. Eventually I found one and bought it for $200 at Amazon.

GPU upgrade is coming…

Micro-Stuttering effect

Posted by zdravko on 14 Jul 2012 | Tagged as: Cool, Tech

Have you got a nice graphical card (and expensive one too) to put it in good use within your computer, which turned out not to be so good for gaming after all (hint, hint Crysis at max settings.) Then you decided to see yourself with a second identical card just to enable SLI / Crossfile and (theoretically) double the GPU performance, and at the end of the day what you see is that the perceived result is not so good as you had expected. And even it is worst compare to single card setup! Why so? Ever heard of phenomenon known as micro-stuttering? Welcome to the club!

Until today it was not so easy to measure the micro-stuttering effect you might see. Just released (as a pre-release) the GPU MIST tool can do that and produce a percentage number (a science bit analysis output) which shows how much your framerate is being affected (read degrade) from micro-stuttering. Download after the jump.

Greylisting explained

Posted by zdravko on 27 Oct 2010 | Tagged as: Cool, Tech

Well, I bet you know what a SPAM e-mail message is, so I am not going to explain it to you. I will show you rather how to fight SPAM. One of the most powerful tools against SPAM to chose from is the Greylisting. And it happens that the last day there was a SPAM storm attack against a server running this tool, which is a perfect example how it works in real world. Take a look at the following picture:

Greylisting in Action

I will explain it step by step:

  1. Greylisting will “temporarily reject” any email from a sender it does not recognize (putting it in Pending queue – represented by the blue line).
  2. If the mail is legitimate the originating server will (after a delay) try again, and provided a sufficient time had elapsed, the email will be accepted (moving it from Pending to Verified queue – represented by the green fill).
  3. If the mail is from a SPAM-er, who is being sending many SPAM emails to thousands-or-more recipients, it probably would not be retried, thus time out (timed-out entries are deleted from Pending queue).

In the above example, which is using real data statistics, almost 1000 servers have tried to communicate to that particular server in timeframe of just 4 hours, each of them probably trying to send 100-or-more of SPAM emails. Imagine what amount of SPAM has been filtered out by just implementing a simple Greylisting implementation. Good job, right?

Edit: The issue had auto-resolved in 24 hours (timed-out entries deleted), as it’s visible from the picture below:

Greylisting Resolved

1billion <> 1billion

Posted by zdravko on 06 Oct 2010 | Tagged as: Tech

A friend asked me why in one of my programs I am counting transferred bytes in KiB and MiB-s; why I am not using easy-for-read Kb, MB, GB prefixes we all are familiar with? And the answer is… because it is just NOT right! More detailed explanation after the jump:

http://lpar.ath0.com/2008/07/15/si-unit-prefixes-a-plea-for-sanity/

“Everyone knows that 1MB is 1024KB, unless you are talking about DVDs, or reading manufacturer specs for a hard drive, and that is just the hard drive manufacturers being stupid. Everyone knows that “K” on a computer means 1024; except for speeds, where it means 1000, except for file download speeds where it means 1024, except when it is the speed of your modem, when it is 1000. Everyone knows that. What, are you stupid?”

A new project arised!

Posted by zdravko on 07 Jul 2010 | Tagged as: Cool, Tech

Well, you will have to see it by yourself (aha, deja vu) to believe it. Yubiii Preview has been posted at 5Group. Already looking for it?!… (:

Yubiii

2-Factor Yubikey Authentication

Posted by zdravko on 08 Jun 2010 | Tagged as: Cool, Tech

YubiKey
Since I just received my Yubikey from Yubico I was eager using it, so I decided to start with my WP blog. It turned out to be an easy 2-step process once I’ve installed YubiKey WordPress plug-in:

  1. Enabled the plug-in and entered the yubico API key info from here;
  2. Entered my Yubikey OTP in my user’s account settings, and that’s it!

The latest Yubikeys firmware supports 2 configurations – one is preloaded from Yubico. Both can be re-programmed to have two independent and separate configurations, including any two of the three alternatives:

  • Standard YubiKey 44 character pass code;
  • Up to 64 character static pass code;
  • OATH-HOTP 6 or 8 digit code identity.

The result: From now on, I will need to provide my username/password and Yubikey OTP in order to login to my blog. Yubiiiiiiii!…

Overclocking day, again

Posted by zdravko on 28 Feb 2010 | Tagged as: Cool, Tech

Hi there! Again, Overclocking day post. Its has been a while since my last OC day, but I have great news for you:

First, ASUS had released new BIOS versions (for various boards) with improved OC features which refine AMD Core unlocking! Yes, indeed, my AMD Phenom X2 550 processor was recognized as X4 with 4 cores working and unlocked. Pity, Windows always stopped with BSOD no matter what I did. But ASUS did their job well, and in BIOS settings under Unleashed more, you can specify which cores to be unlocked. In my case the faulty core was #3 (starting from zero). So, I was able to boot and load in Windows successfully with 3 working cores: #0, #1 and #2.

Second, I needed a better OC tool to stress the 3 cores. It happened that Orthos is running on 2 cores only, and Prime95 I don’t like since it downloads some data chunks to process, then uploads results. So, a new OC tool was born, and it’s named FFT-z! You can see it in action on the screenshots bellow, next to CPU-z, HWMonitor, FurMark, K10stat and TaskManager applications. FFT-z is not released yet officially, but you can grab a public preview release from here. Expect some new cool features added to it In the next releases.

GodMode in Windows 7

Posted by zdravko on 12 Jan 2010 | Tagged as: Tech

Are you already using Windows 7? Well, create a new folder name it “GodMode.{ED7BA470-8E54-465E-825C-99712043E01C}” (without quotes) and hit Enter. Hahaaa Icon changed you see. So open it, to see what’s inside (:

Cleaning up corporate temporary files

Posted by zdravko on 07 Jan 2010 | Tagged as: Cool, Tech

Imagine your company has hundreds if not thousands of computers. Imagine they are running for at least of a year. How many applications, updates, SP-s were installed meanwhile? How many unused files are left after that? How many temporary files were placed anywhere on those computers? Are your users complaining their computers are getting slow, or that their system drive is full? You want to cleanup! But how?

First of all you download Cleanup Temporary Files (shortly “Cle”) tool. The you setup Logon script for your Active Directory’s users (or OU-s, if you prefer) as this:

REM -- Startup script "user.bat"
REM -- Cleanups the PC temporary and unused files from
REM -- various (hidden) places.
\\SRV-DFS\Files\Audit\cleanup\Cle.exe /custom 32839 /p

then on each user Logon this will happen in the top left corner of the Desktop:

Of course all this could be managed from Cle Configuration application, which brings lots of settings and allows you to cleanup custom specified folders. You can tune up the GUI as well, even you can disable the visuals at all, so Cle would work quietly in the background. Corporate admins could deploy a company-wide Cleanup Policy easily using command-line switches as shows above, and force it to computers using “/s” option.

Noted the magic number parameter after the “/custom”? Well it could be easily obtained from Windows Registry (using regedit.exe) once you have run Cle Configuration. It should be specified as a decimal and not hexadecimal number. Here is its location in the Registry:

Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\5GROUP\Cle]
"Selection"=dword:00008047 (32839)

and here is a screenshot of Cle’s Configuration dialog:

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