chg_dir: Change Direction Image for CVAPS

Description Usage Arguments Value References Examples

View source: R/chg_dir.R

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

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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

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## 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)

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