Read grid maps from image files. More...

Read grid maps from image files.

The mapfile driver reads a occupancy grid map from a bitmap image file and provides the map to others via the map interface. Since gdk-pixbuf is used to load the file, pretty much all bitmap formats are supported.

Each cell in an occupancy grid map takes 1 of 3 states: occupied (1), unknown (0), and free (-1). The mapfile driver converts each pixel of an image to a cell with one of these states in the following way: average the color values; divide this average by max value to get a ratio; if this ratio is greater than .95, the cell is occupied; if ratio is less than 0.1, the cell is free; otherwise it is unknown. In other words, "blacker" pixels are occupied, "whiter" pixels are free, and those in between are unknown.

Note that map devices produce no data; the map is delivered via a sequence of configuration requests.

Compile-time dependencies
Configuration requests
Configuration file options
  name "mapfile"
  provides ["map:0"]
  filename "mymap.pgm"
  resolution 0.1  # 10cm per pixel
Brian Gerkey

Last updated 25 May 2011 21:17:00