As you may know, QGifer is a simple software, that allows you to convert video files to GIF images. It also have some useful functions, like crop video, add text to images, apply filters and many more.
The downside is that you have to cut the part of the video you want to gif, but this can be easily done with some cli tools like ffmpeg, mencoder or avconv.
The latest version available is QGifer 2.3 RC2, which has been released a while ago.
Because it is available via PPA, installing QGifer on Ubuntu 15.10 Wily Werewolf, Ubuntu 14.04 Trusty Tahr, Linux Mint 17.x, Elementary OS 0.3 Freya and other Ubuntu derivative systems is easy.
All you need to do is add the PPA to your system, update the local repository index and install the qgifer package:
$ sudo add-apt-repository ppa:samrog131/ppa
$ sudo apt-get update
$ sudo apt-get install qgifer
Optional, to remove qgifer, do:
$ sudo apt-get remove qgifer