Chromatic aberration reduction based on the use of nonlinear poisson equation

This paper presents a chromatic aberration (CA) reduction technique to remove the lateral CA and longitudinal CA, simultaneously. In general, most visible CA-related artifacts appear locally in the neighborhoods of strong edges. Since these artifacts usually have local characteristics, they cannot be removed well by the conventional methods based on global warping methods. Therefore, we designed a partial differential equation (PDE) in which the characteristics of CA are taken into account. The PDE leads to the nonlinear Poisson equation by using Eular-lagrange equation. The proposed Poisson equation matches the gradients of the edges in the red and blue channels to that in the green channel, which results in an alignment of the position of the edges while simultaneously performing a deblurring process on the edges. Experimental results show that the proposed method can effectively remove even significant CA artifacts such as the purple fringing artifact.