fill_time: Fill NA data cube pixels by simple time series interpolation

In appelmar/gdalcubes_R: Earth Observation Data Cubes from Satellite Image Collections

Fill NA data cube pixels by simple time series interpolation

Description

Create a proxy data cube, which fills NA pixels of a data cube by nearest neighbor or linear time series interpolation.

Usage

fill_time(cube, method = "near")

Arguments

cube	source data cube
method	interpolation method, can be "near" (nearest neighbor), "linear" (linear interpolation), "locf" (last observation carried forward), or "nocb" (next observation carried backward)

Details

Please notice that completely empty (NA) time series will not be filled, i.e. the result cube might still contain NA values.

Value

a proxy data cube object

Note

This function returns a proxy object, i.e., it will not start any computations besides deriving the shape of the result.

Examples

# create image collection from example Landsat data only 
# if not already done in other examples
if (!file.exists(file.path(tempdir(), "L8.db"))) {
  L8_files <- list.files(system.file("L8NY18", package = "gdalcubes"),
                         ".TIF", recursive = TRUE, full.names = TRUE)
  create_image_collection(L8_files, "L8_L1TP", file.path(tempdir(), "L8.db"), quiet = TRUE) 
}
L8.col = image_collection(file.path(tempdir(), "L8.db"))
v = cube_view(extent=list(left=388941.2, right=766552.4, 
              bottom=4345299, top=4744931, t0="2018-01", t1="2018-12"),
              srs="EPSG:32618", nx = 497, ny=526, dt="P3M", aggregation = "median")
L8.cube = raster_cube(L8.col, v, mask=image_mask("BQA", bits=4, values=16))
L8.rgb = select_bands(L8.cube, c("B02", "B03", "B04"))
L8.filled = fill_time(L8.rgb, "linear")
L8.filled


plot(L8.filled, rgb=3:1, zlim=c(5000,12000))

appelmar/gdalcubes_R documentation built on March 9, 2024, 10:23 a.m.