  We study a ferromagnetic Ising model with a staggered cell-board magnetic
field previously proposed for image processing [Maruani et al., Markov
Processes Relat. Fields 1 (1995) \cite{MPS}]. We complement previous results on
the existence of phase transitions at low temperature [Gonz\'alez-Navarrete et
al., J. Stat. Phys. 162 (2016)] by determining bounds to the region of
uniqueness of Gibbs measures. We establish sufficient rigorous uniqueness
conditions derived from three different criteria: (1) Dobrushin criterion
[Dobrushin, Theory Probab. Appl. 13 (1968)], (2) Disagreement percolation [van
den Berg and Maes, Ann. Probab. 22 (1994)] and (3) Dobrushin-Shlosman criteria
[Dobrushin and Shlosman, in Statistical Physics and Dynamical Systems. Rigorous
Results. (1985)]. These conditions are subsequently solved numerically and the
resulting uniqueness regions compared.
