GetCDLImage: Request images of the CDL data

In CropScapeR: Access Cropland Data Layer Data via the 'CropScape' Web Service

Request images of the CDL data

Description

A function that requests images of the CDL data for an area of interests in a given year from the CropScape. This function implements the GetCDLImage service provided by the CropScape https://nassgeodata.gmu.edu/CropScape.

Usage

GetCDLImage(
  aoi = NULL,
  year = NULL,
  type = NULL,
  format = "png",
  crs = NULL,
  destfile = NULL,
  verbose = TRUE,
  tol_time = 20
)

Arguments

aoi	Area of interest. Can be a 5-digit FIPS code of a county, 2-digit FIPS code of a state, four corner points or an sf object that defines a rectangle (or a box) area, multiple coordinates that defines a polygon, or a URL of an compressed ESRI shapefile.
year	Year of data. Should be a 4-digit numeric value.
type	Type of the selected AOI. 'f' for state or county, 'b' for box area, 'ps' for polygon, 's' for ESRI shapefile.
format	Format of the image file. Can be png or kml.
crs	Coordinate system. NULL if use the default coordinate system (i.e., Albers projection); Use '+init=epsg:4326' for longitude/latitude.
destfile	A character string that specifies the directory to save the downloaded image file (e.g., 'C:/image.png'). Note that the name of the image file should be specified as well. If not providing destfile, the function will create a temporary folder to save the image file.
verbose	TRUE/FALSE. Display the directory saving the file or not.
tol_time	Number of seconds to wait for a response until giving up. Default is 20 seconds.

Details

The usage of this function is similar to the GetCDLData function. Please see the help page of the GetCDLData function for details. Note that the aoi cannot be a single point here.

Value

The function downloads an image file in png or kml format to users' computer. This function is different to GetCDLData that returns a raster TIF file.

CropScapeR documentation built on Feb. 16, 2023, 9:32 p.m.