"We compute a mask for the object pixels, and use this mask to inpaint the background using the PatchMatch algorithm [Barnes et al. 2009]"
PaintMatch algorithm: http://gfx.cs.princeton.edu/pubs/Barnes_2009_PAR/index.php
PaintMatch algorithm: http://gfx.cs.princeton.edu/pubs/Barnes_2009_PAR/index.php