The sound of phonographic records is contained in the radial position of the groove (and sometimes also its depth). The sound is usually extracted by a mechanical device (the stylus of the record player). Many old records are in such bad shape that no mechanical contact is possible. An alternative is to take a picture of the record and to estimate the radial groove position, using image processing. In this paper, we present the technique to extract the radial position of the groove and therefore the sound of the records.