Adjusts image points to source points — dc

Computes the positions of the adjusted points by fitting image points to source points. Note that points generated by the dc_generate_positions_from_durations function and by the dc_move_from_reference_point do not need to be adjusted.

Usage

dc_adjust(source_points, image_points, adjustment_type = "euclidean")

Arguments

source_points: The source point layer, sf POINT object
image_points: The layer of point to be adjusted to fit source_points, sf POINT object
adjustment_type: The adjustment type to use, either "euclidean" or "affine"

Value

A list object with the transformation matrix, various metrics and the adjusted points

Examples

library(sf)
#> Linking to GEOS 3.12.1, GDAL 3.8.4, PROJ 9.4.0; sf_use_s2() is TRUE

# Read source points
source_pts <- st_read(
  dsn = system.file("gpkg/data-prefecture.gpkg", package = "distanamo"),
  layer = "prefecture", quiet = TRUE
)

# Read non adjusted image points
image_pts_not_adj <- st_read(
  dsn = system.file("gpkg/data-prefecture.gpkg", package = "distanamo"),
  layer = "image-points-not-adjusted", quiet = TRUE
)

# Read the background layer to deform
background_layer <- st_read(
  dsn = system.file("gpkg/data-prefecture.gpkg", package = "distanamo"),
  layer = "departement", quiet = TRUE
)

# Adjust image points to source points
adj_result <- dc_adjust(
  source_points = source_pts,
  image_points = image_pts_not_adj,
  "euclidean"
)

# Use adjusted points to create the interpolation grid
igrid <- dc_create(
  source_points = source_pts,
  image_points = adj_result$image_points,
  precision = 2,
  bbox = st_bbox(background_layer)
)

# Deform the target layer
background_deformed <- dc_interpolate(
  interpolation_grid = igrid,
  layer_to_deform = background_layer
)