original image's aspect ratio is always preserved, even if this means
making the image smaller than the specified size.
-You can also pass `alt`, `class` and `id` parameters. These are passed through
-unchanged to the html img tag.
+You can also pass `alt`, `title`, `class` and `id` parameters. These are
+passed through unchanged to the html img tag. If you include a `caption`
+parameter, the caption will be displayed centered beneath the image.
The `link` parameter is used to control whether the scaled down image links
to the full size version. By default it does; set "link=somepage" to link