sudo add-apt-repository ppa:otto-kesselgulasch/gimp
sudo apt-get update
sudo apt-get install gimp
sudo apt-get install gimp-plugin-registry
Install Resynthesizer Plugin with following command (It is not from above PPA):
sudo apt-get install gimp-resynthesizer
Gimp 2.8 Rc1 for Ubuntu 11.10
gimp
gimp
To install Gimp 2.8 rc-1 on Ubuntu 11.10 Oneiric/Linux Mint 12 open Terminal (Press Ctrl+Alt+T) and copy the following commands in the Terminal:
sudo apt-get install libgdk-pixbuf2.0-0
sudo add-apt-repository ppa:otto-kesselgulasch/gimp
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install gimp
http://www.noobslab.com/2012/04/install-gimp-28-on-ubuntu-1204-precise.html