Extract sf Polygons from geosam or geosam_image Object

Converts detection masks to sf polygon geometries.

Usage

sam_as_sf(x, min_area = NULL, max_area = NULL)

Arguments

x

A geosam or geosam_image object.

min_area

Minimum object area. For geosam, in square meters. For geosam_image, in square pixels. Objects smaller are filtered out.

max_area

Maximum object area. For geosam, in square meters. For geosam_image, in square pixels. Objects larger are filtered out.

Value

An sf data frame with polygon geometries, scores, and area. Returns NULL if no polygons remain after filtering.

Details

For geosam objects (georeferenced imagery), returns polygons in WGS84 coordinates with area in square meters.

For geosam_image objects (non-georeferenced images), returns polygons in pixel coordinates where x = column (from left) and y = row (from top).

Examples

if (FALSE) { # \dontrun{
# Georeferenced imagery
result <- sam_detect(image = "satellite.tif", text = "building")
buildings <- sam_as_sf(result, min_area = 100)

# Non-georeferenced image
result <- sam_image("photo.jpg", text = "dog")
dogs <- sam_as_sf(result)  # coordinates in pixels
} # }