1. An encoding system for determining position and position changes of a moving member, comprising: a sequence of encoder marks forming incremental patterns and at least one index pattern, wherein two subsequent incremental patterns are indicative of an incremental position-change of the moving member and the index pattern is indicative of a reference position of the moving member; a sensor arrangement viewing a section of the encoder-mark sequence, the length of which is greater than one position-change increment; an analyzer arranged to analyze an encoder-mark pattern in the viewed section with regard to the incremental patterns and the index pattern and to generate, in response to a pattern match found, at least one of an incremental-position-change signal and an index signal.