With this option it is possible to read most kind of raster image formats, and convert them to a grid of squares z(x,y).
The typical use is to convert topographic images into a structured mesh.
This importer is implemented as a Tcl plugin, using the GDAL package (Geospatial Data Abstraction Library).
Some of the allowed raster formats are *.tif,*.png,*.gif,*.jpg, GIS Arc/Info grids, etc.
Raster images are a 2D structured grid of NxM points with values or each point, like the RGB color or current images, to encode topographical information like height, or other kind of data like land use.
There are some two extra options:
Create geometry: If it is selected then they are created geometrical entities (points, lines, surfaces)
Create mesh: they are created preprocess mesh entities (nodes and quadrilaterals)
Convert Arc/Info ASCII: write a new file with .txt extension in Arc/Info ASCII format
Increment: To allow subsampling data for big files, jumping by this value rows and columns of original data. It is set to 1 by default to take into account all data.