(Quick Reference)
                img
Purpose
Renders an HTML 
<img> tag for an image resource.
This tag uses 
g:resource to generate the link to the resource, so it is implicitly aware of the 
Resources plugin.
Examples
Example usages for the "shop" app:
<g:img dir="images" file="logo.png" width="40" height="40"/>
Output: <img src="/shop/images/logo.png" width="40" height="40"/><g:img uri="/images/icons/add.png"/>
Output: <img src="/shop/images/logo.png"/>
Note that if the Resources plugin is installed this will defer to 
<r:img> which will include any HTML attributes defined in the image's resource definition, if one exists.
Description
Attributes
- base(optional) - Sets the prefix to be added to the link target address, typically an absolute server URL. This overrides the behaviour of the- absoluteproperty if both are specified.
- contextPath(optional) - the context path to use (relative to the application context path). Defaults to "" or path to the plugin for a plugin view or template.
- dir(optional) - the name of the directory containing the resource
- file(optional) - the name of the resource file
- absolute(optional) - If- truewill prefix the link target address with the value of the- grails.serverURLproperty from- application.groovy, or http://localhost:<port> if there is no setting in- application.groovyand not running in production.
- plugin(optional) - The plugin to look for the resource in
- uri(optional) - If using the Resources plugin, the uri of the image. A more terse alternative to using the dir/file attributes.
Source