makeDynamicChipsSF: makeDynamicChipsSF

In geodl: Geospatial Semantic Segmentation with Torch and Terra

makeDynamicChipsSF

Description

Generate a vector point sf object of chip center locations for use with defineDynamicSegDataSet().

Usage

makeDynamicChipsSF(
  featPth,
  featName,
  extentPth,
  extentName,
  extentCrop = 50,
  imgPth,
  imgName,
  doBackground = FALSE,
  backgroundCnt,
  backgroundDist,
  useSeed = FALSE,
  seed,
  doShuffle = FALSE
)

Arguments

featPth	Full folder path or relative path to vector features. Must include final forward slash.
featName	File name of reference features including file extension.
extentPth	Full folder path or relative path to vector extent. Must include final forward slash.
extentName	File name of extent including file extension.
extentCrop	Amount to crop extent to avoid edge effects. We recommend cropping the extent more than the size of the chips you will use to avoid chips with NA cells. Default is 50 cells.
imgPth	Path to image or predictor variable raster data. Must include the final forward slash
imgName	File name of image or predictor variable raster data including file extension
doBackground	Whether or not to randomly select background cells. Default is FALSE.
backgroundCnt	Number of background cells to select.
backgroundDist	Minimum allowed distance between randomly selected background locations and boundaries of reference features.
useSeed	Whether or not to set a random seed for replicability. Default is FALSE.
seed	Random seed value.
doShuffle	Whether or to shuffle the rows in the resulting table. Default is FALSE or no shuffling.

Details

Requires an input vector object of feature examples, a boundary extent, and the path and name of the associated raster predictor variables. Note that the raster predictor variable must cover the full spatial extent defined by the extent object. If not, a smaller extent should be defined for which predictor variables are available.

The input vector features must contain a "code" column of numeric class codes and a "class" column of text class names. If the data are not spatial contiguous, we recommend reserving code 0 for the background class.

The extent can be cropped to avoid generating chips without a full set of cells available. We recommend cropping by a factor larger than 50% the width/height of the desired chip size.

The tool returns a sf dataframe with class name ("class"), class numeric code ("code"), path to the image or predictor variables ("imgPth"), name of the image or predictor variables ("imgName"), the path to the input features ("featPth"), the file name of the input features ("featName"), the file path to the extent ("extentPth"), the file name for the extent ("extentName"), and the point feature geometry ("geometry").

Value

sf dataframe object of center locations for chip creation with associated information as attributes.

geodl documentation built on Nov. 12, 2025, 5:07 p.m.