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When documents are written on both sides, the ink might bleed through the paper. This is particularly true with old documents. Reading and studying such documents is not easy when serious bleed through is present. This report proposes a solution to correct the problem and shows how the first part of this solution, the registration process, was implemented. Using image processing techniques, the bleed through can be removed using thresholds but not before the recto and verso sides have been properly registered. First, both sides of the document are digitized. The verso is then flipped and corrected so that the bleed through coordinates of one side correspond exactly with the coordinates of the original writing on the other. This needs to be done because both sides are not scanned precisely the same way and there might be a shift and a rotation difference between the two. To do this we use an affine transformation of six parameters. The parameters are found by optimizing the alignment process. Performance is an issue when applying this algorithm on large size images and techniques are used to create a sample set of pixels, which will be used to estimate the results. It was found that by uniformly choosing only some pixel horizontally and vertically the performance was greatl