PhenoMetrics: Phenologic metrics from time series vegetation index data

Description Usage Arguments Value See Also Examples

Description

This function extracts 15 Phenological metrics that indicate the growth conditon of crops, from multi-temporal vegetaion index images.

Usage

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PhenoMetrics(VIStack, ROI = NULL, Percentage = NULL, Smoothing = NULL)

Arguments

VIStack

- RasterStack - a raster stack from whichthe time series extracted

ROI

- a polygon designated for region of interest. It can be spatialPolygon object or extent.

Percentage

- Optional Numeric Vlaue - percentage of minimum NDVI value at which the Onset and Offset is defined. The 'Percentage' paramenter is optional; if not provided, a Default value of 20 will be taken.

Smoothing

- Optional logical value - if the user chooses to use smoothed curve or row/unsmoothed curve. If "Smoothing' is set to TRUE, the moving avegare filter will be applied to the vegetation index curve. The default value, if not provided, is FALSE, then the unsmoothed row data be used for the analysis.

Value

A RasterStack of 15 phenoloical metric images in the order of OnsetV, OnsetT, MaxV, MaxT, OffsetV, OffsetT, LengthGS, BeforeMaxT, AfterMaxT, GreenUpSlope, BrownDownSlope, TINDVI, TINDVIBeforeMax, TINDVIAfterMax, Asymmetry

See Also

MultiPointsPlot, PhenoPlot

Examples

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#EXAMPLE
ExampleROI<- readOGR (system.file("extdata","ROI.shp", package="CropPhenology"))
ExampleStack<- stack (system.file("extdata", "ExampleStack.grd", package="CropPhenology"))
PhenoStack<- PhenoMetrics (ExampleStack,ExampleROI )
CropPhenology::PhenoPlot(PhenoStack)

SofanitAraya/CropPhenology documentation built on May 9, 2019, 1:51 p.m.