Gunturk-Altunbasak-Mersereau Alternating Projections Image Demosaicking

The problem of image demosaicking (or demosaicing) is where an image has been captured through a color lter array (CFA), and the goal is to estimate complete color information at every pixel. This IPOL article describes the image demosaicking method proposed by Gunturk, Altunbasak, and Mersereau in \Color Plane Interpolation Using Alternating Projections." Given an initial demosaicking, the method improves the result by alternatingly applying two dierent projections. One projection copies the green channel’s wavelet detail coecients to the red and blue channels while the other projection constrains the solution to agree with the observed data.