This is a suite of ten Gimp plugins known as the 'Resynthesizer'. The most commonly used is 'Heal selection' but all use the plugin whose full interface is found at 'Filters>Map>Resynthesize.'
resynthesizer.tar.gz is an archive for Linux.
Resynthesizer_v1.0-i686.zip is an archive for Windows.
The plugins require Gimp and Python. (Or, there exists a script-fu 'Heal selection' plugin that does not require Python.)
To install, download the appropriate file, uncompress it, and copy the files to the standard place for Gimp plugins.