BandUP is a code that allows you to obtain a primitive cell representation of the band structure of systems simulated using supercells. The unfolding of the bands is performed as described in the following papers:

Paulo V. C. Medeiros, Sven Stafström and Jonas Björk, Phys. Rev. B 89, 041407(R) (2014)

Paulo V. C. Medeiros, Stepan S. Tsirkin, Sven Stafström and Jonas Björk, Phys. Rev. B 91, 041116(R) (2015)