Build and Analyse Sentinel-2 Time Series

{sen2rts} is an R library which helps to extract and manage time series from Sentinel-2 archives created with the package {sen2r}.

This package is currently under development (beta version).

Functionalities currently implemented in the package are summarised below. A wider overview is presented in the vignette “The sen2rts workflows”, which shows a simple, reproducible use case to obtain a smoothed equally-weighted time series, isolate cycles and extract metrics, explaining how the currently implemented functions can be used to perform a common workflow. For documentation about specific functions, see the Reference page.

Installation

Currently {sen2rts} is not on CRAN; it can be installed from GitHub:

install.packages("remotes")
remotes::install_github("ranghetti/sen2rts")

In case of troubles related to the installation of {sen2r}, whose {sen2rts} depends, refer to sen2r installation page.

Usage

The following minimal example synthetically shows how to perform the main steps provided by the package; refer to this vignette for a wider explanation.

library(sen2rts)

## Create a Sentinel-2 derived archive using sen2r
#  (see sen2r documentation at https://sen2r.ranghetti.info/ )
#  and read the paths of the raster using function load_s2paths()
#
#  (in this examples, sample data are used)
sen2r_ndvi_paths <- sample_paths("NDVI") # NDVI images (target product)
sen2r_scl_paths <- sample_paths("SCL")   # SCL images (quality flag)

## Extract, smooth and gap fill time series
data("sampleroi") # Sample spatial features for data extraction
ts_raw <- extract_s2ts(sen2r_ndvi_paths, sampleroi, scl_paths = sen2r_scl_paths)
# extract time series over sampleroi extension
ts_smoothed <- smooth_s2ts(ts_raw) # smooth time series
ts_filled <- fill_s2ts(ts_smoothed) # gap filling (daily time series)

## Phenological fitting and extraction
dt_cycles <- cut_cycles(ts_filled) # cut vegetation cycles
cf <- fit_curve(ts_filled, dt_cycles) # fit double logistic curves
dt_pheno <- extract_pheno(cf) # extract phenological metrics

## Plot results
plot(ts_filled, pheno = dt_pheno, plot_points = TRUE)

Credits

{sen2rts} is being developed by Luigi Ranghetti (IREA-CNR), and it is released under the GNU General Public License version 3 (GPL‑3).

The sen2rts logo, partially derived from the R logo, is released under the Creative Commons Attribution-ShareAlike 4.0 International license (CC-BY-SA 4.0).

To cite this library, please use the entry reported below.

L. Ranghetti (2021). “sen2rts: Build and Analyse Sentinel-2 Time Series”. R package version 0.4.0.9000. doi: 10.5281/zenodo.4682829, URL: https://sen2rts.ranghetti.info.

@Manual{sen2rts_manual,
  author = {Luigi Ranghetti},
  title = {sen2rts: Build and Analyse Sentinel-2 Time Series},
  year = {2021},
  doi = {10.5281/zenodo.4682829},
  url = {https://sen2rts.ranghetti.info},
  note = {R package version 0.4.0.9000},
}

Contributing

This project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms.