auto_chg_detect: Perform change detection for two Landsat CDR surface...

Description Usage Arguments Value References

View source: R/auto_chg_detect.R

Description

This image automates the change detection process using the Change Vector Analysis in Posterior Probability Space (CVAPS) algorithm. The threshold for change/no-change mapping is determined using Huang's algorithm (see threshold or can be specified manually. First the images should be classified using the auto_classify function (or any other classification approach that yields per-pixel probabilities of class membership).

Usage

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auto_chg_detect(t1_classes, t1_probs, t2_probs, output_path, output_basename,
  ext = "tif", overwrite = FALSE, chg_threshold = NULL, notify = print)

Arguments

t1_classes

cover classes as output from auto_classify_image for time 1 image

t1_probs

per class probabilities as output from auto_classify_image for time 1 image

t2_probs

per class probabilities as output from auto_classify_image for time 2 image

output_path

the path to use for the output

output_basename

the base filename for output files from auto_chg_detect (without an extension)

ext

file extension to use when saving output rasters (determines output file format).

overwrite

whether to overwrite existing files (otherwise an error will be raised)

chg_threshold

the threshold to use determining change and no-change areas from the change magnitude image (see chg_mag. If NULL, then threshold will be used to dermine this threshold value automatically. A threshold in the range of .75-1 is recommended as a starting point.

notify

notifier to use (defaults to print function). See the notifyR package for one way of sending notifications from R. The notify function should accept a string as the only argument.

Value

nothing - used for the side effect of performing change detection

References

Chen, J., X. Chen, X. Cui, and J. Chen. 2011. Change vector analysis in posterior probability space: a new method for land cover change detection. IEEE Geoscience and Remote Sensing Letters 8:317-321.


azvoleff/teamlucc documentation built on June 4, 2017, 12:08 a.m.