If you are generating output files using HTMLOUTPUTFILE and IMAGEOUTPUTFILE that are in a different directory to the weathermap installation, then the HTML will probably contain an incorrect IMG tag. This keyword allows you to replace the IMG SRC attribute in the HTML output with a corrected one.

The equivalent command-line option (--image-uri) takes precedence over this configuration line, if both are used.

If you are generating maps using the Cacti plugin, then this directive is ignored, as the filename and uri are calculated instead.