The best open source alternative to scrot is maim. If that doesn't suit you, our users have ranked six alternatives to scrot and four of them is open source so hopefully you can find a suitable replacement. Other interesting open source alternatives to scrot are shotgun (screenshot utility) (Free, Open Source), Gnome Screenshot (Free, Open Source) and Hyperdesktop (Free, Open Source).
GNOME Screenshot is a utility used in the GNOME desktop environment for taking screenshots. It was part of the GNOME Utilities (gnome-utils) package, but was split into its own package for the 3.3.1 version in 2011.
Other than being an uploading tool for Imgur, it also allows you to take screenshots and perform simple editing functions on them. You can capture the complete screen or a selected region of your screen.