BISE: Best Index Slope Extraction

In ozjimbob/ecbtools: Environmental Change Biology Tools

Description

Best Index Slope Extraction (BISE) function for removing noise from satellite NDVI data.

Usage

BISE(x, slide_period = 20, slope_threshold=0.2)

Arguments

x	A sequence of equally-spaced values, for example, from daily NDVI or meteorological data.
slide_period	Days to look ahead for decrease.
slope_threshold	Percentage decrease threshold.

Details

This is a simple implementation of the BISE algorithm for reducing noise in time-series data where sudden drops in value (for example, due to cloud in satellite imagery) should be ignored. It is based on Viovy et al. 1992.

Value

A vector of corrected data.

Author(s)

Grant Williamson

References

Viovy, N., Arino, O., & Belwards, A.S. (1992) The Best Index Slope Extraction (BISE): A method for reducing noise in NDVI time-series. International Journal of Remote Sensing. 13:8, 1585-1590.

Examples

h=c(seq(10,90,2),seq(90,10,-2))
h=h+rnorm(82,0,10)
o=BISE(h)
plot(h)
lines(o)

ozjimbob/ecbtools documentation built on Jan. 18, 2021, 7:39 p.m.