this project combines F0 detection and note segmentation,it achieve a good result.
onset detection method cite this paper
@conference {rgong2018singing,
title = {Singing voice phoneme segmentation by hierarchically inferring syllable and phoneme onset positions},
booktitle = {Interspeech 2018},
year = {2018},
month = {02/09/2018},
address = {Hyderabad, India},
url = {https://arxiv.org/pdf/1806.01665.pdf},
author = {Rong Gong and Xavier Serra}
}