A sufficient descent conjugate gradient method for impulse
noise removal
Peiting Gao, Yongfei Wu*
ABSTRACT: In this paper, we introduce a modified PRP-type conjugate gradient (CG) method for impulse noise removal
in the second phase of the two-phase method. A nice property of the scheme is that the search direction at each iteration
satisfies the sufficient descent condition independent of any line search. Under the Armijo-type line search, its global
convergence result is proved. Numerical comparison is given to illustrate that the proposed method for removing
impulse noise is promising.