AgCropCount Task

This task locates and counts crops in high-resolution, single-band images.

This task requires a separate license for the ENVI Crop Science Module; contact your sales representative for more information.

Example

This example performs the following steps:

Opens an RGB image of emerging cotton plants, captured by an unmanned aerial vehicle (UAV). Image courtesy of Drone Global Network.
Runs AgCropCount Task on the green band of the image, to count the crops and to create an ENVIAgCrops object.
Prints the ENVIAgCrops object properties.

; Start the application

e = ENVI(/HEADLESS)

; Open an input file

File = Filepath('Cotton.dat', $

SUBDIR=['data','crop_science'], $

ROOT_DIR=e.Root_Dir)

Raster = e.OpenRaster(File)

; Process the green band

subset = ENVISubsetRaster(Raster, BANDS=[1])

; Get the task from the catalog of ENVITasks

Task = ENVITask('AgCropCount')

; Define inputs

Task.INPUT_RASTER = subset

Task.INCLUDE_EDGES ='true'

Task.MINIMUM_CROP_DIAMETER = 9 ;pixels

Task.MAXIMUM_CROP_DIAMETER = 12

Task.NUMBER_OF_INCREMENTS= 12

Task.GAUSSIAN_FACTOR = 0.8

Task.PERCENT_OVERLAP = 60

Task.INTENSITY_THRESHOLD = 0.81

; Run the task

Task.Execute

; Get the output ENVIAgCrops object

outCrops = Task.OUTPUT_CROPS

; Print the properties of the crop object

Print, outCrops

Syntax

Result = ENVITask('AgCropCount')

Input parameters (Set, Get): GAUSSIAN_FACTOR, INCLUDE_EDGES, INPUT_RASTER, INTENSITY_THRESHOLD, MAXIMUM_CROP_DIAMETER, MINIMUM_CROP_DIAMETER, NUMBER_OF_INCREMENTS, OUTPUT_CROPS_URI, PERCENT_OVERLAP

Output parameters (Get only):OUTPUT_CROPS, OUTPUT_NCROPS

Parameters marked as "Set" are those that you can set to specific values. You can also retrieve their current values any time. Parameters marked as "Get" are those whose values you can retrieve but not set.

Input Parameters

GAUSSIAN_FACTOR (optional)

Specify a Gaussian smoothing factor to use before searching for crops. This is the fraction of the maximum search diameter at which smoothing should occur. To disable Gaussian smoothing, set GAUSSIAN_FACTOR to 0.

INCLUDE_EDGES (optional)

Set this parameter to true to count partial crops touching the edges of the image or any masked area that surrounds the area to be counted. Also set it to true when applying a mask within the area being counted, for example, when masking out non-vegetation pixels. The default is false.

INPUT_RASTER (required)

Specify a single-band raster as input.

INTENSITY_THRESHOLD (optional)

Specify the fraction of the maximum crop intensity, below which crop detections will be removed.

MAXIMUM_CROP_DIAMETER (required)

Specify the maximum crop diameter. The diameter is measured in meters if the input raster has a standard spatial reference. Otherwise, specify the number of pixels for the diameter.

MINIMUM_CROP_DIAMETER (required)

Specify the minimum crop diameter. The diameter is measured in meters if the input raster has a standard spatial reference. Otherwise, specify the number of pixels for the diameter.

AgCropCount Task works best when the minimum and maximum crop diameters do not differ greatly in size. For example, a range of 1 to 4 meters will produce better results than a range of 1 to 16 meters. If your area of interest has a wide range of crop diameters, consider splitting up the area into separate images to process, each with a similar range of crop diameters.

NUMBER_OF_INCREMENTS (optional)

Specify the number of increments to use when searching crops. Use this parameter in conjunction with MAXIMUM_CROP_DIAMETER and MINIMUM_CROP_DIAMETER. The number of increments includes the minimum and maximum diameters. The default value is 5. For example, if the minimum crop diameter is 1 meter and the maximum crop diameter is 5 meters, setting the number of increments to 5 will search for crops of exactly 1, 2, 3, 4, and 5 meters.

OUTPUT_CROPS_URI (optional)

Specify a string with the fully qualified filename and path for the output JSON file that will contain the crop data.

PERCENT_OVERLAP (optional)

Specify the percentage of allowable overlap between crops before one of them is removed from consideration. The default value is 50.0. To disable the overlapping percentage, set PERCENT_OVERLAP to 100. To allow no overlapping at all, set PERCENT_OVERLAP to 0. Enter smaller values if the crops are distinctly separated from one another.