Musical punctuation on the microlevel: Automatic identification and performance of small melodic units

In this investigation we use the term musical punctuation for the marking of melodic structure by commas inserted at the boundaries that separate small structural units. Two models are presented that automatically try to locate the positions of such commas. They both use the score as the input and operate with a short context of maximally five notes. The first model is based on a set of subrules. One group of subrules mark possible comma positions, each provided with a weight value. Another group alters or removes these weight values according to different conditions. The second model is an artificial neural network using a similar input as that used by the rule system. The commas proposed by either model are realized in terms of micropauses and of small lengthenings of interonset durations. The models are evaluated by using a set of 52 musical excerpts, which were marked with punctuations according to the preference of an expert performer.