Using Images with HTML

Introduction

One of the more popular features of Mosaic is that it is easily extended to support differing types of image types. By itself, Mosaic supports the Compuserve GIF format for images. Any image in GIF format can be included directly into Mosaic. To use other image formats such as rgb, tiff, postscript, or jpeg you must rely upon helper programs. These helper programs are specific to each platform and called by mosaic when an image type other than GIF is found. Since this is platform specific you should try to use image formats that are well supported across platforms. I recommed postscript and jpeg as two popular formats. Also, remember that an image that looks wonderful on a 24 bit color SGI may not look so good on a 4 bit SVGA monitor.

Embedding GIF Images

The NCSA Mosaic manual has a section on In-line Images which you can read.

This method doesn't allow you to align images in the middle of the screen. By enclosing the IMG URL with a preformatted text directive you can space the URL and get it placed where you want it.

External Images, Sounds, and Animation

This is platform dependent. However the NCSA Mosaic manual offers the following information on including external images, sounds, and animations.

Creating Image Maps

Creating image maps is really two steps. First, sections of the image must be defined as clickable regions, and second, URL's defined that map to that region.

Luckily, both steps can now be automated by a wonderful program called mapedit under Unix. This is a Unix application that will allow you define image regions and associate URL's to them via an X11 graphical interface. The mapedit program can be run by entering the command mapedit at the system prompt. At UMBC we are using the CERN WWW deamon so you should save your image maps in that format.