We present a new image processing strategy that enables an automated comparison of striation patterns. A signal model is introduced to describe the interesting features of forensically relevant striation marks. To provide a high image quality, several images of the same surface area are recorded under systematically varying conditions and then combined for an improved result by means of data fusion techniques. Based on the signal model, the signal of interest is concentrated, and a compact representation of the marks is obtained. To enable an efficient description of the relevant features, even in the cases of deformed surfaces or curved striation marks, a straightening of the grooves is performed beforehand. Following, a meaningful "signature" describing the information of interest is extracted using the whole length of the grooves. This signature is used for an objective evaluation of similarity of the striation patterns.