Spews

Spews can be the solution you seek for automating the process of changing the desktop wallpaper and a useful tool for those who rapidly get tired of viewing the same background picture every day.
The application is nothing more than a wallpaper switcher that can periodically modify the current background. In a sector that is infused with similar utilities, Spews is distinctive through ease of use and the possibility to pause its actions in case specific programs are running.
All the configuration options are comprised within a single window, no extra menus to navigate through. Despite this, the GUI is rather uncluttered, offering fast access to each setting.
You can add multiple source directories that contain the set of pictures you want the application to rotate and select just the ones you want to use at a certain point. Options for changing the wallpaper display style are available, together with background color customization possibilities.
As expected, you can set the time interval a picture should be shown onto the desktop, which range from a few seconds to a few hours.
The 'Exclusion' section is probably the top feature of Spews. You can specify games or resource-demanding programs that you want to include in this list. If the application detects even one of the processes as active, then wallpaper switching is immediately disabled.
With support for most popular graphic formats, Spews can modify the desktop background image according to a given schedule, saving you the effort of manually performing this operation.