Image segmentation by hand — image_segment

This R code is a function that allows the user to manually segment an image based on the parameters provided. This only works in an interactive section.

Usage

image_segment_manual(
  img,
  shape = c("free", "circle", "rectangle"),
  type = c("select", "remove"),
  viewer = get_pliman_viewer(),
  resize = TRUE,
  edge = 5,
  plot = TRUE
)

Arguments

img: An Image object.
shape: The type of shape to use. Defaults to "free". Other possible values are "circle" and "rectangle". Partial matching is allowed.
type: The type of segmentation. By default (type = "select") objects are selected. Use type = "remove" to remove the selected area from the image.
viewer: The viewer option. If not provided, the value is retrieved using get_pliman_viewer(). This option controls the type of viewer to use for interactive plotting. The available options are "base" and "mapview". If set to "base", the base R graphics system is used for interactive plotting. If set to "mapview", the mapview package is used. To set this argument globally for all functions in the package, you can use the set_pliman_viewer() function. For example, you can run set_pliman_viewer("mapview") to set the viewer option to "mapview" for all functions.
resize: By default, the segmented object is resized to fill the original image size. Use resize = FALSE to keep the segmented object in the original scale.
edge: Number of pixels to add in the edge of the segmented object when resize = TRUE. Defaults to 5.
plot: Plot the segmented object? Defaults to TRUE.

Value

A list with the segmented image and the mask used for segmentation.

Details

If the shape is "free", it allows the user to draw a perimeter to select/remove objects. If the shape is "circle", it allows the user to click on the center and edge of the circle to define the desired area. If the shape is "rectangle", it allows the user to select two points to define the area.

Examples

if (interactive()) {
img <- image_pliman("la_leaves.jpg")
seg <- image_segment_manual(img)
plot(seg$mask)

}