lsMosaic: Mosaic a set of Landsat-7 or Landsat-8 images

In RGISTools: Handling Multiplatform Satellite Images

Description

lsMosaic merges the Landsat-7 or Landsat-8 imagery that covers a region of interest on the same dates.

Usage

lsMosaic(
  src,
  AppRoot,
  region,
  out.name = "outfile",
  verbose = FALSE,
  gutils = TRUE,
  overwrite = FALSE,
  ...
)

Arguments

src	the path to the folder with the Landsat-7 or Landsa-8 images in GTiff format.
AppRoot	the directory to save the mosaicked images.
region	a Spatial*, projected raster*, or sf class object defining the area of interest.
out.name	the name of the folder that stores the outputs. By default, “outfile” is assigned.
verbose	logical argument. If TRUE, the function prints the running steps and warnings.
gutils	logical argument. If TRUE, the function uses ‘GDAL’ utilities for mosaicking.
overwrite	logical argument. If TRUE, overwrites the existing images with the same name.
...	arguments for nested functions: pathrow a list of vectors with the path and row numbers of the tiles concerning the region of interest. This argument is mandatory if region is not provided. bFilter a vector with the bands to be mosaicked. If not supplied, all bands are mosaicked. dates a vector with the capturing dates being considered for mosaicking. If not supplied, all dates are mosaicked.

Details

The function mosaics the imagery in the src folder. The folder can hold GTiff images from several tiles, dates and bands. When only a subset of dates has to be mosaicked, the dates should be provided through the argument dateFilter. The dates must be provided as a Date class objects. For further details about the bFilter argument go to lsDownload.Once mosaicked, the images can be cropped to fit the extent (optional). The extent can be defined in any coordinate reference system, since lsMosaic automatically reprojects the extent to match the projection of the image. The outputs are placed in the AppRoot directory, under the folder named as out.name. If no name is provided, the folder isn named “outfile”. To use 'gutils = TRUE', a proper installation of ‘GDAL’ and the 'gdalUtils' library is required. This method is faster than native ‘R’ functions.

Value

this function does not return anything. It saves the imagery in the AppRoot directory.

Examples

## Not run: 
# load a spatial polygon object of Navarre
data(ex.navarre)
# main output directory
wdir <- file.path(tempdir(),"Path_for_downloading_folder")
print(wdir)
# download Landsat-8 images
lsDownSearch(satellite = "ls8",
             username = "username",
             password = "password",
             startDate = as.Date("01-01-2018", "%d-%m-%Y"),
             endDate = as.Date("20-01-2018", "%d-%m-%Y"),
             extent = ex.navarre,
             untar = TRUE,
             AppRoot = wdir)
# folder with the Landsat-8 untared images
wdir.ls8 <- file.path(wdir, "Landsat8")
tif.src <- file.path(wdir.ls8,"untar")
# mosaic the Landsat-8 images
lsMosaic(src = tif.src,
         AppRoot = wdir.ls8,
         out.name = "Navarre",
         extent = ex.navarre,
         gutils = TRUE, # using gdalUtils
         overwrite = TRUE) # overwrite

## End(Not run)

RGISTools documentation built on July 2, 2020, 3:58 a.m.