TheiaCollection: A collection of tiles from Theia

In norival/theiaR: Download and Manage Data from Theia

A collection of tiles from Theia

Description

Generate and manage collection of tiles from Theia. This collection can be created either from a cart file ('.meta4') downloaded from Theia website, from a TheiaQuery object or from a list of TheiaTile (not implemented yet).

Usage

   c <- TheiaCollection$new(cart.path = NULL,
                            tiles     = NULL,
                            query     = NULL,
                            dir.path  = NULL,
                            check     = TRUE)
                            quiet     = TRUE)

   c$download(auth, overwrite = FALSE, check = TRUE, quiet = TRUE)
   c$check()
   c$status
   c$extract(overwrite = FALSE, dest.dir = NULL)
   c$read(bands)
   c$as_gdalcube(out.file = "gdalcube_collection.sqlite")

Arguments

c:

A TheiaCollection object

dir.path:

The path to the directory containing zip files

check:

Whether or not to check existing files on collection's creation

quiet:

Control verbose output

tiles:

A list of TheiaTile objects

cart:

An XML cart parsed from a 'meta4' file downloaded from Theia

website. Used only if Collection is created from a cart

query:

A TheiaQuery object, used only if collection is created from a TheiaQuery object. Can also be a list with search terms. In this case, it will create a 'TheiaQuery' object from it. See TheiaQuery for details on query syntax

auth:

A character string giving the file path to Theia credentials. Or a TheiaAuth object

overwrite:

Overwrite existing tiles (default to 'FALSE')

bands:

A character vector of bands to load from tiles

out.file:

Filename to store gdalcubes' image collection

Details

TheiaCollection$new() Create a new instance of the class

c$download(overwrite = FALSE, check = TRUE) Download the tiles of the collection and check the resulting files

$ccheck() Check the tiles of the collection

c$status Return the status of each tile of the collection

c$extract(overwrite = FALSE, dest.dir = NULL) Extract archives to dest.dir if supplied, or to the same directory as the archives otherwise

c$read(bands) Read requested bands, apply corrections on values (as specified in Theia's product information), and return a list of RasterStack objects (one stack per tile)

c$as_gdalcube(out.file) Create a 'gdalcubes' image collection from downloaded tiles. See https://github.com/appelmar/gdalcubes_R for more details.

Examples

# Create a collection from a query
## Create a query to Theia database, looking for tiles from Sentinel2
## satellite around Grenoble, between 2018-07-01 and 2018-07-06.

query <- list(collection = "SENTINEL2",
              town       = "Grenoble",
              start.date = "2018-07-01",
              end.date   = "2018-07-06")

## Create a collecion of tiles from this query
mycollection <- TheiaCollection$new(query = query, dir.path = ".")

print(mycollection)


# Alternatively, you can create a collection from a cart file (that you can
# download from Theia's website)
cart.path <- system.file("extdata", "cart.meta4", package = "theiaR")

mycollection <- TheiaCollection$new(cart.path = cart.path,
                                    dir.path  = ".")

print(mycollection)

## Not run: 
# Download the tiles in the collection
mycollection$download()

## End(Not run)

## Not run: 
# Finally, you can extract zip archives containing the tiles
mycollection$extract(overwrite = FALSE)

## End(Not run)

norival/theiaR documentation built on Feb. 6, 2023, 3:51 a.m.