Abstract
The Hardanger fiddle is a variety of the violin used in the folk music of the western and central part of southern Norway. This paper presents a dataset of several hours of recordings of Hardanger fiddle music, with note annotations of onsets, offsets and pitches, provided by the performers themselves. A subset has also been annotated with beat onset positions by the performer as well as three expert musicians. The complexity of the music genre—polyphonic, highly ornamented and with a very irregular pulsation, among other aspects—motivated the design of a new annotation software adapted to these particular needs. Beat annotation in MIR is typically recorded as positions in seconds, without explicit connection with actual musical events. In the context of music where the rhythm is carried by the melodic instrument alone, a more reliable definition of beat onsets consists in associating them with the onsets of the notes that represent the start of each beat. This latter definition of beat onsets reflects that beats are generated from within the flow of played melodic-rhythmic events, which implies that the spacing of beats may be shifting and irregular. This motivated the design of a new method for beat annotation in Hardanger fiddle music based on a selection of notes in the note annotation. Comparisons between annotators through alignment—integrated in the interface—enable them to eventually correct their annotations or observe alternative valid interpretations of any given excerpt. After dedicating a part of the note annotation dataset to the training of a machine learning model, for the task of assessing both note pitch and onset time, an F1 score of 87% can be reached. The beat annotation dataset demonstrates the necessity of developing new beat trackers adapted to Hardanger fiddle music. The dataset as well as the annotation software is made publicly available.