Outline Object

Outline Object is an extension built for Paint.net users, which enables them to outline objects within images as well as to change their width and colors. It's geared toward those with some minimal experience in working with this particular image editing application.

Unlike most software products, it's not wrapped in a setup kit. Instead, it's packed in a single and small-sized DLL file that can be quickly downloaded and copied to the "Effects" folder of Paint.net's installed directory. This also works if you have a portable edition of the graphic editor.

If the photo processor is already launched, you have to restart it to finalize setup and gain access to the new plugin. It's stored under the "Effects" menu and "Object" submenu.

The photo must have a transparent area which surrounds the object you're attempting to outline. Outline Object doesn't come equipped with a built-in color picker, so it's necessary to select the outline's color from the standard color docker window.

The configuration panel is small and contains a couple of customizable options, thus letting you set the outline radius and strength by moving two sliders or by entering their numerical values. Each setting can be restored to default with one click.

Although it hasn't been updated for a long time, it integrated with the most recent Paint.net version successfully in our tests, without triggering it to hang, crash or display error messages throughout its runtime.

On the other hand, Outline Object is difficult to handle by beginners who don't know how to use the color docker window for outlining colors. Nevertheless, you can test it for yourself, especially if you're an advanced Paint.net user.