Image Overviews, Tiling and Pyramids - Open Source Geospatial Tools: Applications in Earth Observation - page 85

Fig. 7.1 Pyramid with four levels for an image of 4,096 × 4,096 pixels. The tile size is 256 × 256
pixels
7.1 gdaltindex
Given a set of georeferenced input raster files, gdaltindex creates a (or appends
to an existing) vector dataset with a feature for each input file. The feature attributes
contain the filenames and the polygon geometries of the respective outlines of the
rasters. For instance, you can visualize the geographical bounding box of one or more
raster images in a virtual globe such as Google Earth. From GDAL version 2.0 the
output reference coordinate system and format can be set accordingly (EPSG:4326
in KML format). For older versions, the vector Shapefile can be converted to KML
with ogr2ogr . The output of gdaltindex is also suitable for use with UMN
MapServer as a raster tileindex.