Systematic database creation for expressive singing voice synthesis control

In the context of singing voice synthesis, the generation of the synthesizer controls is a key aspect to obtain expressive performances. In our case, we use a system that selects, transforms and concatenates units of short melodic contours from a recorded database. This paper proposes a systematic procedure for the creation of such database. The aim is to cover relevant style-dependent combinations of features such as note duration, pitch interval and note strength. The higher the percentage of covered combinations is, the less transformed the units will be in order to match a target score. At the same time, it is also important that units are musically meaningful according to the target style. In order to create a style-dependent database, the melodic combinations of features to cover are identified, statistically modeled and grouped by similarity. Then, short melodic exercises of four measures are created following a dynamic programming algorithm. The Viterbi cost functions deal with the statistically observed context transitions, harmony, position within the measure and readability. The final systematic score database is formed by the sequence of the obtained melodic exercises.