Two-step methods for image zooming using duality strategies
Tingting Wu, Yu-Fei Yang, Huichao Jing · Numerical Algebra Control and Optimization · 2014
In this paper we propose two two-step methods for image zoomingusing duality strategies. In the first method, instead of smoothingthe normal vector directly as did in the first step of the classicalLOT model, we reconstruct the unit normal vector by means ofChambolle's dual formulation. Then, we adopt the split Bregmaniteration to obtain the zoomed image in the second step. The secondmethod is based on the TV-Stokes model. By smoothing the tangentialvector and imposing the divergence free condition, we propose animage zooming method based on the TV-Stokes model using the dualformulation. Furthermore, we give the convergence analysis of theproposed algorithms. Numerical experiments show the efficiency ofthe proposed methods.