16.  Web Filters

Revision History
Revision $Revision: 1.0 $ 2006-12-27 j.h

Only one filter in this group for the moment: “ImageMap”.

16.1.  ImageMap

Revision History
Revision $Revision: 1943 $ 2006-12-27 j.h

In Web sensitive images are frequently used to get some effects when defined areas are enabled by the pointer. Obviously the most used effect is a dynamic link to another web page when one of the sensitive areas is clicked on. This “filter” allows you to design easily sensitive areas within an image. Web site design softwares have this as a standard function. In GIMP you can do this in a similar way.

16.1.1.  Overview

This plug-in lets you design graphically and friendly all areas you want to delimit over your displayed image. You get the relevant part of html tags that must be merged into the right place in your page html code. You can define some actions linked to these areas too.

This is a complex tool which is not completely described here (it works about like Web page makers offering this function). However we want to describe here some of the most current handlings. If you want, you can find a more complete descriptions in Grokking the GIMP with the link [GROKKING02].

16.1.2.  Activate the filter

From an image window, you can find this filter through FiltersWebImageMap

So you get this window:

Figure 15.293.  Plug-in opened window

Plug-in opened window

Opening example with Wilber's image

The window is a small one, but you can magnify it. The main useful areas are:

  • completely on the left are vertically displayed icons, one for pointing, three for calling tools to generate various shape areas, one to edit zone properties, and finally one to erase a selected zone; you can call these functions with the Mapping menu,

  • just on the right is your working area where you can draw all the shapes areas you want with the relevant tools,

  • on the right is displayed an icon vertical set; its use is obvious but a help pop-up gives you some information about each function,

  • finally, even on the right is a display area, as a property list of the created areas. A click on one item of the list selects automatically the corresponding shape in the working area,

16.1.3.  Options

With the menu EditPreferences you can choose some web useful options within the different docks.

With the menu View you can work with a Grayscale display

With the menu Tools you can create guides and even regulary spaced rectangular areas.

Figure 15.294.  ImageMap options

ImageMap options

Example with circle and polygon areas

When you select a mapped area within the list, the corresponding shape is automatically selected in your working area; then you can modify it.

[Caution] Caution

Contrary to other filters, this plug-in doesn't make an image but a text file. So you must save your work in a text format.

[Tip] Tip

In the plug-in you can open the saved text file. The areas defined in your file will be loaded and overdisplayed; if the displayed image is not the original one or not with the same size, GIMP will ask you for adapting the scale.