geodl (version 0.3.1)

makeMasks: makeMasks

Description

Make raster mask from input vector data

Usage

makeMasks(
  image,
  features,
  crop = FALSE,
  extent,
  field,
  background = 0,
  outImage,
  outMask,
  mode = "Both"
)

Value

Single-band raster mask written to disk in TIFF format and, optionally, a copy of the image written to disk. Cropping may be applied as specified. No R objects are returned.

Arguments

image

File name and full path or path relative to working directory for image. Image is converted to a SpatRaster internally.

features

File name and full path or path relative to working directory for vector mask or label data. A field should be provided that differentiates classes using unique numeric codes. If the input features use a different coordinate reference system then the input image, the features will be reprojected to match the image. Vector data are converted to a SpatVector object internally.

crop

TRUE or FALSE. Whether or not to crop the input image data relative to a defined vector extent. The default is FALSE.

extent

File name and full path or path relative to working directory for vector extent data. If the extent uses a different coordinate reference system then the input image, the features will be reprojected to match the image. Vector data are converted to a SpatVector object internally.

field

The name of the field in the feature vector data that differentiates classes using a unique numeric code with an integer data type. Field name should be provided as a string.

background

The numeric value to assign to the background class. The default is 0. If the full spatial extent has labels in the input feature data, no background value will be applied. For binary classification problems, the background should be coded to 0 and the positive case should be coded to 1. It is not necessary to include the background class in the vector feature data.

outImage

Image output name in TIFF format (".tif") with full path or path relative to working directory for image. This output will only be generated if the mode is set to "Both".

outMask

Mask output name in TIFF format (".tif") with full path or path relative to working directory for image. Output will be a single-band raster grid of class numeric codes.

mode

Either "Both" or "Mask". If "Both", a copy of the image will be made along with the generated raster mask. If "Mask", only the mask is produced. If you are experiencing issues with alignment between the image and associated mask, setting the mode to "Both" can alleviate this issue. However, this will result in more data being written to disk.

Details

This function creates a raster mask from input vector data. The cell value is indicated by the field parameter. A unique numeric code should be provided for each class. In the case of a binary classification, 0 should indicate background and 1 should indicate positive. For a multiclass problem, values should be sequential from 0 to n-1, where n is the number of classes, or 1 to n. We recommend using 1 to n. If no cropping is applied, the generated raster mask will have the same spatial extent, number of rows of pixels, number of columns of pixels, cell size, and coordinate reference system as the input image.

Examples

if (FALSE) {
makeMasks(image = "INPUT IMAGE FILE AND PATH",
          features = "INPUT VECTOR FEATURES FILE AND PATH",
          crop = TRUE,
          extent = "INPUT VECTOR BOUNDARY and PATH",
          field = "ATTRIBUTE COLUMN NAME",
          background = 0,
          outImage = "OUTPUT IMAGE NAME AND PATH",
          outMask = "OUTPUT MASK NAME AND PATH",
          mode = "Both")
}