Computing Trivia

This article applies to Android applications in Windows using IntelliJ IDEA development tools. Windows 7 was used in this example but the explanation will work for other recent versions of Windows. It is quite a task learning how to use mobile application development tools. This page describes how to digitally sign your .apk file which is the  Android application package file. In short, your Android program file. Once you have created an APK file to launch it, simply copy to your device and use the Android file manager to install it. The picture below shows the digital signature keystore file, the unsigned APK file and the signed APK file. The procedure of signing the APK file is quite straighforward but first you must ensure your Java JDK is properly installed and that the Java tools are accessible on your commandline (Windows command console - what used to be called the DOS window). Most important is that your PATH environmental variable (In Windows 7 find thi...

Video DVDs contain files that are named "Something.vob" where VOB stands for Video OBject. In fact, it is an MPEG video file and can be played by any software capable of playing MPEG. I tried to make a copy of one of my DVDs for a friend (this DVD is not copyrighted) but could not copy the .VOB files. Programs such as Roxio burn, ImgBurn, CD Recovery Toolbox etc. all failed to read the DVD. It seems there was a scratch on the disc that followed the circular tracks of the DVD which supposedly is the most difficult to deal with. There are different solutions offered on various places on the web  including using banana peel.   The one that worked for me was  white BATA shoe cream  shown below: The cream is pretty old and almost solid but I rubbed a little onto white tissue paper then placed a few drops of water on the spot and used this mixture to gently rub on the DVD surface. The water helped to spread the  polish. I then rubbed gently with wet tissue tha...

How to Install RIOT Plugin for GIMP::  Since this article was first written a stand-alone version of RIOT has been made available Download the plugin from   http://luci.criosweb.ro/riot/download/   Select the download link titled " RIOT as plug-in for other applications "    Launch the  Riot-plugin.exe  file by double clicking. The installer installs all the files including Riot.exe, Riot.dll, and FreeImage.dll in the location where you installed GIMP  If GIMP is open, close it and re-launch it. To optimise an image, open it then save with menu  File->Save for web with RIOT    You can set the target file size by selecting " Compress to size " button  on bottom right corner of optimised image pane and providing the size in kilobytes. Alternatively you can use a slider provided to allow you to change the quality while showing you a preview of the resulting image. Enjoy .       ...

This particular modem is a ZTE HSUPA MF637U modem. Click on images to see enlarged view. Let's get started: OS is Linux Mint version 15. Yours may be older or newer. Plug in the modem to a free USB port and check that it recognises the modem as a drive in the File Manager whose icon is shown below third from left and the File Manager view is also shown with the modem listed as the "MODEM-SDSK" drive: Fig. 1. Linux Mint Desktop Panel Fig 2. Linux Mint File Manager view showing listed drives at left and Application Manu at top. Click on image to see enlarged view. 3. Go to the Applications Menu shown in Fig. 2 and select Settings>Network Connections Fig. 3. Network Connections dialogue. Click on image to see enlarged view. 4.  Select Add > Mobile Broadband then click  "Create" 5. Follow the wizard to select the device, country, billing plan, service provider and deafult settings. Fig. 4. Safaricom default set...