chg_dir: Change Direction Image for CVAPS

In yinscapital/sat-locat-reference-team-lucc: TEAM land use and cover change data processing toolkit

Description

This code calculate the change direction image for the Change Vector Analysis in Posterior Probability Space (CVAPS) method of Chen et al. 2011. Use the change direction image in conjunction with the change magnitude image from chg_dir, and DFPS to use the Double Window Flexible Pace Search method (Chen et al. 2003) to determine the threshold to use to map areas of change and no-change.

Usage

chg_dir(t1p, t2p, filename, overwrite = FALSE, verbose = FALSE, ...)

Arguments

t1p	time 0 posterior probability Raster*
t2p	time 1 posterior probability Raster*
filename	(optional) filename for output change direction RasterLayer
overwrite	whether to overwrite existing files (otherwise an error will be raised)
verbose	whether to print detailed status messages
...	additional parameters to pass to rasterEngine

Value

Raster* object with change direction image

References

Chen, J., P. Gong, C. He, R. Pu, and P. Shi. 2003. Land-use/land-cover change detection using improved change-vector analysis. Photogrammetric Engineering and Remote Sensing 69:369-380.

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.

Examples

## Not run: 
t0_train_data <- get_pixels(L5TSR_1986, L5TSR_1986_2001_training, "class_1986",training=.6)
t0_model <- train_classifier(t0_train_data)
t0_preds <- classify(L5TSR_1986, t0_model)
t1_train_data <- get_pixels(L5TSR_2001, L5TSR_1986_2001_training, "class_2001", training=.6)
t1_model <- train_classifier(t1_train_data)
t1_preds <- classify(L5TSR_2001, t1_model)
t0_t1_chgdir <- chg_dir(t0_preds$probs, t1_preds$probs)

## End(Not run)

yinscapital/sat-locat-reference-team-lucc documentation built on May 14, 2019, 11:09 a.m.