Digital restoration of ancient color manuscripts from geometrically misaligned recto-verso pairs

We propose a fast automatic procedure for registration and restoration of images of recto-verso pairsof color manuscripts affected by bleed-through distortion. The registration algorithm assumes a rigidprojective deformation of a side with respect to the other. The coefficients of the geometric transformationare computed from a large number of pairs of matching points, automatically detected by exploiting theestimates of local shifts between pairs of small patches. We validate the efficiency of the registrationalgorithm through the performance of a restoration method based on a model that relates each coupleof corresponding pixels in the two images, and thus requiring a very accurate alignment of the twosides. The experiments show that this combined procedure of registration plus restoration can providean excellent removal of the bleed-through pattern, while leaving unaltered the salient features of theoriginal manuscript.