You may have installed new applications, however those new applications come with not so new icons. They may provide you with ugly low resolution icons. Or you may have installed a beautiful icon theme like Numix-Circle and may be wondering why some of your icons have not changed. Never fair, you do not have to suffer with the presence of these low resolution icons, as the solution is simpler than you might think.
First look for the Application.
This is the AVI Demux application icon. Alexander obtained this variant of the application from getdeb.net as it was more up-to-date than the one present within the official repositories. As you can see, this application has decided to stick its low resolution icon instead of using the one present in the Numix-Circle icon suite.
In order to solve this problem we must first understand the basics of how Ubuntu handles applications and their icons.
Ubuntu stores the Unity Dash shortcut configuration files in /usr/share/applications
All configuration files in this directory feature a .desktop extension to indicate that it is an application launcher configuration file.
And all icons referenced by those configuration files are normally stored in the /usr/share/icons directory.
You will need to gain root access to edit the configuration files. This is Ubuntu’s way of protecting you from yourself, so to speak. A lot of things could go wrong if you were to be the root user 24/7 for this very reason you are not a “root” user.
First open a Terminal window (Ctrl + Alt + T) and type sudo nautilus
This will open a Nautilus window with root privileges.
Go to usr/share/applications
The following window will appear:
As you can see, the Avidemux icons “appear” to be present in this folder. This is not the case as these are simply just shortcuts referring to the actual icons located in usr/share/icons
Let us go there and investigate.
You can see that the icon Alexander Lindo has highlighted is avidemux.svg. It is there but it is not appearing in the launcher or the dash. This simply means that the application’s shortcut configuration file is not referencing the icon from the Numix-Circle icon suite but is actually sourcing its icon from another directory (either from within the usr/share/icons folder or sometimes in it’s own folder).
An example of this is the Xdiagnose application. It sources its icon from /usr/share/xdiagnose/icons/microscope.svg
This means that, no matter what icon theme you use it will completely ignore it.This can be resoloved using the same method mentioned in this tutorial.
Close all your open windows and then close your terminal window.
Open a terminal window and type sudo gedit
This will open up the text editor with root privileges, enabling to edit configuration files editable only by the root user.
Hit the “Open” button and navigate to usr/share/applications
Click avidemux2.6-qt.desktop and click Open
The following window will appear:
Look at the Icon field. You can see it says: avidemux2.6-qt
Change this to avidemux and hit Save.
Or, alternatively, If you would like to have a backup in case you mess up just comment out the Icon=avidemux2.6-qt with a # so it will look like #Icon=avidemux2.6-qt
The field will become blue indicating that it is inactive.
Now you can hit Enter and type: Icon=avidemux in the next line.
Hit Save, close all windows, log out and log back in and you’re done.