Inlined Images for NCSA Mosaic

Introduction

NCSA Mosaic supports inlined bitmaps and images in X bitmap and GIF formats. For example, here is a bitmap: . Here is a bitmap serving as an anchor to another document: .

How It Works

To embed a bitmap or image in a HTML document, use the IMG tag. For example:

<IMG SRC="http://foobar.com/foobar.xbm"> To use a bitmap or image as an anchor, do something like this: <A HREF="http://foobar.com/blagh.html"> <IMG SRC="http://foobar.com/foobaz.gif"> </A> This causes the GIF image named foobar.gif to be used as an anchor to the document named blagh.html. When a bitmap or an image serves as an anchor, it is surrounded by a colored rectangle and made sensitive to mouse clicks, just like ordinary text anchors.

Note that the value of a SRC argument is a Uniform Resource Locator --- image data can thus lie anywhere on the network; it is retrieved as the document is being formatted by Mosaic. Once image data has been retrieved once, it is cached in memory, so subsequent uses of the same image will be generally very quick.

For example, . Using this bitmap (which was also used above) twice in the same document incurred very little additional overhead.

Alignment

You can choose to have inlined images top aligned or bottom aligned with their surrounding text. Here's a top aligned image: . The next paragraph will begin with a bottom aligned image.

That was a bottom aligned image. Whether an inlined image is top aligned or bottom aligned is determined by the (optional) ALIGN attribute to the IMG element: the choices are ALIGN=TOP and ALIGN=BOTTOM (default is top). Here's how image of Dan at the start of this paragraph was specified: <IMG ALIGN=BOTTOM SRC="../Demo/quayle.xbm">.

Currently, text cannot be made to cleanly flow around an image. This is a known drawback in HTML and is due to be corrected in HTML's successor.

Another Demo

OK, now that you sat through that, here's another demo, this time with color GIF images.

Extensive uses of inlined images can be found here, here, here, and elsewhere.

Acknowledgements

The GIF-reading code NCSA Mosaic uses was written by David Koblas; his copyright statement is here.


National Center for Supercomputing Applications
mosaic-x@ncsa.uiuc.edu