ee_image_to_drive function

Creates a task to export an EE Image to Drive.

Creates a task to export an EE Image to Drive. This function is a wrapper around

ee$batch$Export$image$toDrive(...).

ee_image_to_drive(
  image,
  description = "myExportImageTask",
  folder = "rgee_backup",
  fileNamePrefix = NULL,
  timePrefix = TRUE,
  dimensions = NULL,
  region = NULL,
  scale = NULL,
  crs = NULL,
  crsTransform = NULL,
  maxPixels = NULL,
  shardSize = NULL,
  fileDimensions = NULL,
  skipEmptyTiles = NULL,
  fileFormat = NULL,
  formatOptions = NULL
)

Arguments

• image: Image to be exported.
• description: User-friendly name of the task.
• folder: Folder name in the user's Drive account where the export will be stored. Default is "rgee-backup".
• fileNamePrefix: Prefix for the export filename in Google Drive. Defaults to the task name.
• timePrefix: Prefixes the current date and time to the exported files.
• dimensions: Defines the image dimensions for export. It can be specified as a single positive integer for the maximum dimension or in "WIDTHxHEIGHT" format, where WIDTH and HEIGHT are positive integers.
• region: The lon,lat coordinates for a LinearRing or Polygon specifying the region to export. It can be specified as nested lists of numbers or a serialized string. Defaults to the image's region.
• scale: Image resolution in meters per pixel. Defaults to the native resolution of the image asset unless a crsTransform is specified.
• crs: Coordinate reference system of the exported image's projection. Defaults to the image's default projection.
• crsTransform: A comma-separated string of 6 numbers describing the affine transform of the coordinate reference system of the exported image's projection, in the order: xScale, xShearing, xTranslation, yShearing, yScale, and yTranslation. Defaults to the image's native CRS transform.
• maxPixels: Maximum number of pixels allowed in the exported image. The task will fail if the exported region exceeds this limit in the specified projection. Defaults to 100,000,000.
• shardSize: Size given in pixels of the shards in which the image will be computed. Defaults to 256.
• fileDimensions: Defines the pixel dimensions for each image file when the image size exceeds the capacity of a single file.To indicate a square shape, use a single number; for width and height, use a list of two dimensions. Please note that the image will be clipped to the overall image dimensions. The specified file dimensions must be a multiple of the shardSize.
• skipEmptyTiles: If TRUE, skip writing empty (i.e., fully-masked) image tiles. Defaults to FALSE.
• fileFormat: The string file format to which the image is exported. Currently only 'GeoTIFF' and 'TFRecord' are supported, defaults to 'GeoTIFF'.
• formatOptions: A dictionary of string keys to format-specific options. **kwargs: Holds other keyword arguments that may have been deprecated, such as 'crs_transform', 'driveFolder', and 'driveFileNamePrefix'.

Returns

An unstarted task that exports the image to Drive.

Examples

## Not run:

library(rgee)
library(stars)
library(sf)

ee_users()
ee_Initialize(drive = TRUE)

# Define study area (local -> earth engine)
# Communal Reserve Amarakaeri - Peru
rlist <- list(xmin = -71.13, xmax = -70.95,ymin = -12.89, ymax = -12.73)
ROI <- c(rlist$xmin, rlist$ymin,
         rlist$xmax, rlist$ymin,
         rlist$xmax, rlist$ymax,
         rlist$xmin, rlist$ymax,
         rlist$xmin, rlist$ymin)

ee_ROI <- matrix(ROI, ncol = 2, byrow = TRUE) %>%
  list() %>%
  st_polygon() %>%
  st_sfc() %>%
  st_set_crs(4326) %>%
  sf_as_ee()

# Get the mean annual NDVI for 2011
cloudMaskL457 <- function(image) {
  qa <- image$select("pixel_qa")
  cloud <- qa$bitwiseAnd(32L)$
    And(qa$bitwiseAnd(128L))$
    Or(qa$bitwiseAnd(8L))
  mask2 <- image$mask()$reduce(ee$Reducer$min())
  image <- image$updateMask(cloud$Not())$updateMask(mask2)
  image$normalizedDifference(list("B4", "B3"))
}

ic_l5 <- ee$ImageCollection("LANDSAT/LT05/C01/T1_SR")$
  filterBounds(ee$FeatureCollection(ee_ROI))$
  filterDate("2011-01-01", "2011-12-31")$
  map(cloudMaskL457)

# Create simple composite
mean_l5 <- ic_l5$mean()$rename("NDVI")
mean_l5 <- mean_l5$reproject(crs = "EPSG:4326", scale = 500)
mean_l5_Amarakaeri <- mean_l5$clip(ee_ROI)

# Move results from Earth Engine to Drive
task_img <- ee_image_to_drive(
  image = mean_l5_Amarakaeri,
  fileFormat = "GEO_TIFF",
  region = ee_ROI,
  fileNamePrefix = "my_image_demo"
)

task_img$start()
ee_monitoring(task_img)

# Move results from Drive to local
ee_drive_to_local(task = task_img)
## End(Not run)

See Also

Other image export task creator: ee_image_to_asset(), ee_image_to_gcs()