The WorldImageReader allows access to image data through the GridCoverageExchange interface. This supports raster images with an associated world file .
World files have the same name as the image (different file extension) and contain just enough information to convert pixel coordinates to real world coordinates. They do not store any coordinate reference system information for the coordinates.
The supported formats and associated world file extensions are:
| Image Format | Image Format Extension | World File Extension |
|---|---|---|
| JPEG | .jpg or .jpeg | .jgw |
| TIFF | .tif or .tiff | .tfw |
| PNG | .png | .pgw |
| GIF | .gif | .gfw |
A world file extension of *.wld may be used in place of the format specific extension (ie. *.jpg and *.wld).