# Annotated-VocalSet: A Singing Voice Dataset
## 2 Steps to Generate the Dataset
### Detecting Onsets, Offsets, and Transitions  
After preparing the pitch contours, a semi-automatic approach was used to annotate pitch contours with onset, offset, and transitions. First, the algorithm introduced by [PERSON] and [PERSON] [35] as a state-of-the-art algorithm and explicitly designed for singing signals was used to estimate the onset, offset, and transition between two consecutive notes.  
The onset detection algorithm [35] looks for the trajectory changes in a pitch contour to calculate the onset, offset, and transition. First, the algorithm calculates the slopes of the points in a pitch contour to discover when a significant change happens in the contour.  
Figure 1: An illustration of the Smart-Median algorithm for smoothing pitch contour. The red line shows the pitch contour estimated by an F0 estimator, while the green dashed line is the corrected version of the red line.  
Then, these changes are considered as events, onset, offset, or a transition. The algorithm seeks onsets and offsets for both articulated sounds and rests. In other words, an onset point can be the start of a sound or rest; similarly, an offset can be the end of a sound or rest. As [PERSON] and [PERSON] [35] reported, their algorithm works better than other available onset detection algorithms for singing signals.  
After labelling the events, all the detected events were graphed to double-check the accuracy of the annotations. Some errors observed among the estimated events were then corrected with a software tool developed by this paper's authors; Figure 2 depicts the tool. The software uses different colours for each event. If the user finds an incorrect event, they should edit the CSV file containing the values that will be explained in Section 3.1. Therefore, its users can change the CSV files and immediately see the results on the screen to ensure the events are labelled correctly. This tool was developed using the language C# and is available at [[https://doi.org/10.5281/zenodo.7061507](https://doi.org/10.5281/zenodo.7061507)]([https://doi.org/10.5281/zenodo.7061507](https://doi.org/10.5281/zenodo.7061507)), accessed on 3 August 2022. It should be mentioned that this tool works on CSV files in the \"raw\" folders.  
To adjust the estimated annotations, firstly, files were divided among five unexpert musicians (but they were trained how to interpret a pitch contour to find events) to correct the estimated events. Finally, an expert musician with more than 12 years of music training reviewed all the events and adjusted any incorrect ones.  
Figure 3a depicts the onset, offset, and transition from a part of a pitch contour. The red line shows the offset, the green line is the onset, the blue line shows the start of the transition, and the purple line shows the end of the transition.  
Figure 2: The software tool used to check and correct F0, onset, offset, and transition annotations by indicating them with different colours.  
However, there is an acknowledgement among researchers [1, 4, 5, 12] that there is not a universal agreement as to where to precisely select the onset/offset points in a pitch contour. Therefore, each annotator picks a point approximately between the red and green lines in Figure 3a.  
Therefore, since several software libraries and associated studies do not include transitions but only onsets and/or offsets, we have proposed two approaches, considering and not considering the existence of a transition, for annotating onsets, offsets, and transitions.