The merits of 'TIMESAT' and 'phenopix' are adopted. Besides, a simple and
growing season dividing method and a practical snow elimination method
based on Whittaker were proposed. 7 curve fitting methods and 4 phenology
extraction methods were provided. Parameters boundary are considered for
every curve fitting methods according to their ecological meaning.
And 'optimx' is used to select best optimization method for different
curve fitting methods.
Reference:
Kong, D., (2020). R package: A state-of-the-art Vegetation Phenology extraction
package, phenofit version 0.3.1, <doi:10.5281/zenodo.5150204>;
Kong, D., Zhang, Y., Wang, D., Chen, J., & Gu, X. (2020). Photoperiod Explains
the Asynchronization Between Vegetation Carbon Phenology and Vegetation Greenness
Phenology. Journal of Geophysical Research: Biogeosciences, 125(8), e2020JG005636.
<doi:10.1029/2020JG005636>;
Kong, D., Zhang, Y., Gu, X., & Wang, D. (2019). A robust method for reconstructing
global MODIS EVI time series on the Google Earth Engine.
ISPRS Journal of Photogrammetry and Remote Sensing, 155, 13–24;
Zhang, Q., Kong, D., Shi, P., Singh, V.P., Sun, P., 2018. Vegetation phenology
on the Qinghai-Tibetan Plateau and its response to climate change (1982–2013).
Agric. For. Meteorol. 248, 408–417. <doi:10.1016/j.agrformet.2017.10.026>.
Rcpp, purrr, dplyr, magrittr, lubridate, data.table, zoo,
gridExtra, ggplot2, optimx, ucminf, numDeriv, JuliaCall,
methods, zeallot
knitr, rmarkdown, reshape2, spam, testthat (>= 2.1.0)

Rcpp, purrr, dplyr, stringr, magrittr, lubridate, data.table,
zoo, gridExtra, ggplot2, optimx, ucminf, numDeriv, methods,
zeallot

The package phenology fits a parametric function that describes
phenology
Functions to fit and test the phenology of species based
on counts.
'BE_to_LBLE.R' 'LBLE_to_BE.R' 'Likelihood_phenology.R'
'Lnegbin.R' 'daily_count.R' 'add_SD.R' 'add_format.R'
'extract_result.R' 'fit_phenology.R' 'format_par.R'
'growlnotify.R' 'map_phenology.R' 'par_init.R' 'phenology.R'
'plot_delta.R' 'plot_map.R' 'plot_phenology.R' 'plot_phi.R'
'remove_site.R' 'shift_sinusoid.R' 'phenology-package.R'