R/sen_max_overlap.R

In envima/GEDItools:

#' Get Sentinel 2a overlap
#'
#' This function calculates maximal overlap between sentinel scenes
#' @param inpath_sen characterstring to unzipped folder from sentinel download
#'
#' @keywords clip stack sentinel
#' @export
#' @examples
#' sen_max_overlap
#'
#' @import raster
#'

#inpath_sen <- "C:/Users/Alice/Uni/Projekte/GEDI/data/Sentinel"

sen_max_overlap <- function(inpath_sen){

  ########################################################################################
  ### settings
  ########################################################################################
  setwd(inpath_sen)
  sen_dirs <- list.dirs(inpath_sen, recursive = F)
  sen_ext_lst <- lapply(sen_dirs, function(i){
    # i <- sen_dirs[[1]]
    basenm <- basename(i)
    granule_dir <- list.dirs(paste0(basenm, "/", basenm, ".SAFE/GRANULE/"), recursive = F, full.names = F)
    sen_images <- list.files(paste0(basenm, "/", basenm, ".SAFE/GRANULE/", granule_dir, "/IMG_DATA/R10m/"), full.names =T)
    exmpl_img <- raster::raster(sen_images[1])
    sen_ext <- extent(exmpl_img)
    sen_ext_df <- data.frame(scene = basenm, xmin = xmin(sen_ext), xmax = xmax(sen_ext), ymin = ymin(sen_ext), ymax = ymax(sen_ext))
  })
  ext_all <- do.call(rbind, sen_ext_lst)
  sen_overlap <- c(xmin = max(ext_all$xmin), xmax = min(ext_all$xmax),
                        ymin = max(ext_all$ymin), ymax = min(ext_all$ymax))
  return(sen_overlap)
}