ChBg is for changing desktop backgrounds in a given period. It can render images with 10 modes (such as tiled, centered, scaled, etc.). It uses Imlib1, Imlib2, or gdk_pixbuf for loading images, so it supports many image formats. ChBg has a windowed setup program, is able to load setup files, can be used as slideshow picture previewer in its own window or as a desktop background, and can be used as screensaver or as an xscreensaver hack. It has a dialog for fast previewing of pictures and very usable thumbnail previews.