"POSTIX"

Single-Concept Digital Posters

Dr. Owen E. Thompson, Professor
Ms. Mary Ellen Loftus, Graduate Research Assistant
Department of Meteorology
University of Maryland College Park

SINGLE-CONCEPT EDUCATIONAL MATERIALS
Gifs, Mpegs, Quicktime, AVI, VIS5D, gRADS
Discussion text, Original Links, and Stuff

Have you ever:

... forgotten where you put an interesting digital visual?
... forgotten what the visual was all about?
... forgotten where you got it in the first place?

If your answer to any question was yes, no, or maybe, then this page may be for you.

WHAT IS THE REASON FOR THIS PAGE?

We propose a single-concept web page format, which we call a Postix, as a convenient Web-object for documenting and sharing images, photos, movies, and advanced visualization datafiles. We developed our Postix format for formal educational use in computer-based classroom visualizations, research seminars, and Web-pages for student independent study. However, a Postix approach should be generally convenient for organizing any collection of digital visuals, including vacation photographs, digital art collections, musical clips, and so forth. Samples which we show later focus on college entry-level materials for earth system science education. This should not intimidate readers from adopting the Postix approach for other endeavors.

WHAT IS A Postix?

A Postix is an HTML file format for archiving images, movies, and other computer visualizations. Our convergence to Postix formatted pages provided us a convenient way of archiving a large amount of graphic and visualization material for use in classes, both as in-class lecture aids and out-of-class study materials. Fetching only images or visualization files from other Web sites for use as educational aids provides one with a large directory of assorted "gifs", "mpegs", "quicktimes", and so forth. Unfortunately, the understanding, interpretation, and original source of such visuals too quickly evaporates from one's organic memory. The Postix format is intended to imbed these additional key ingredients all into a single file.

A Postix should have, at minimum, the following key features:

The important inclusion of "Source Reference" links provides some ethical relief in organizing images, visuals, and other datafiles produced by others into an framework tailored for one's own use. For example, we might choose to describe a borrowed visualization for, say, an entry-level college class while the same visualization might be described by someone else in a quite different manner suited to their own needs. A Postix, therefore, might contain one person's visual and another person's discussion. In the traditional world of print publication, this is done by formal agreement. In the open frontier of the Web, each of us should adopt some courtesy about such things. The politeness of the Postix style is to provide proper credit and attribution for freely borrowed materials.

With developing web browser "doodads", there are a variety of Postix styles which might be useful for different purposes. Have a look at the following examples which illustrate possibilities. (We encourage you to copy any pages you wish as templates for developing your own Postix.)

STILL IMAGE Postix

Simple Postix
This Postix shows the minimum requirements of a graphic image, a title, a discussion (college entry-level), and reference information in a single simple web page. The width sizing of this Postix is fixed to provide for hard copy printing. This simple Postix requires a single HTML file containing a link to at least one image file, and all other necessary information. Note that the all parts of the page move within your browser with the single scrollbar.

Postix using "Frames"
This Postix uses the "Frames" extention of HTML, and shows a graphic image, title, discussion, and reference information separated into independent frames within a single web page. A scroll bar appears in the upper frame if image height is greater than the value established in the master html file. The scrollbar in the lower frame scrolls the explanatory text while leaving the image in place. This type of Postix requires three html files (one for the upper frame ["baro1.html"], one for the lower frame ["baro2.html"], and the controlling html file ["baro_F.html"] which you see if you "View Source".

Postix using multiple images and "Frames"
This Postix takes advantage of hyperlinks within its upper graphic "frame" which provides for showing a sequence of images illustrating a single, extended discussion. Each image in the upper frame is a clickable link within an HTML file which advances to the next image in the sequence. The viewer works through the discussion in the lower frame while controlling the images in the upper frame. This particular Postix consists of 8 HTML files: ["ozone1a.html" through "ozone1f.html" for the upper, image frame; "ozone2.html" for the lower text frame; and "ozone_F.html" for the controlling file.

Postix using multiple images and "Frames"
This Postix is nearly identical to the previous one except that obvious hyperlinks are included in each "image page" to allow the selection of any of the images comprising the image set for this Postix. For inspection, this Postix incorporates the 8 HTML files "ozone1xa.html" through "ozone1xf.html", "ozone2.html", and the controlling page, "ozone_Fx.html".

ANIMATED Postix

Animated Postix can include a variety of animation formats, such as "Gif Animations", "MPEG" movies, "Quicktime" movies, "AVI" animations, and so forth. Generally speaking, each type of animation can be handled in the manner of one of the examples below, depending on whether a user's web browser is configured for "helper" applications to show the animation in an external window, or "plugins" to view the animated file in the browser window.

Simple Postix with animated Gif Image
This Postix shows an animated gif of a sequence of stereo satellite images from a U.S. weather satellite (GOES), with title, a discussion, and reference arranged in a single web page. The Postix provides hyperlinks to download either the animated gif image, or a still gif image, or an mpeg movie of this four dimensional cyclone visualization.

Simple Postix with MPEG Animation
This Postix contains a clickable image of one frame of an mpeg movie, title, discussion, and reference in a single page. Clicking the image will launch an external MPEG Movie helper application, or will download the mpeg file, as specified by the configuration of the user's browser. As a courtesy, we recommend showing the byte size of the mpeg movie file so that users can anticipate the download requirements. In this example, the movie viewer is external, so that the entire Postix page (including the single fixed image) can be easily scrolled to read the discussion.

Postix with Embedded MPEG Animation and "Frames"
This Postix has an upper and lower frame within the Postix page, and makes use of "embedded" MPEG animation. In the upper frame, an MPEG movie is "embedded" inline for browsers having an MPEG-Plugin. (Netscape Plugins are currently available for MPEG, Quicktime, and AVI animations for selected hardware platforms, and the types and selection of plugins is very likely to increase quickly for all browsers.) The lower frame contains title, discussion, and reference information. As shown in this example, it is wise to include a text line after the hyperlink for the embedded mpeg file so that users with browsers which do not support MPEG plugins will know that something is missing. Embedding the animation in a separate frame from the text allows the viewer to scroll the text while maintaining the movie animation in clear view. We also recommend that this type of Postix incorprating embedded animations with frames also include a clickable link to the animation through an external viewer, as shown in this example. In this case, the link is directly to an mpeg movie file and not to a Postix linking an mpeg movie file. This is because a link to another Postix would put that page into the upper frame, while a link to the movie file itself launches an external viewer.

ADVANCED VISUALIZATION Postix

There are many software packages for different hardware platforms that munch on data files which themselves can be transfered and documented using a Postix. Certain such software packages are "launchable" directly from a web browser if the software has been configured as a helper application, with mime-type and file extention identified to the browser. Three such packages which are of particular interest to us are STELLA II (which can be configured as a helper application on PC and MAC platforms) and the "Vis5D" and "VisAD" advanced visualization software packages developed by the University of Wisconsin Space Science and Engineering Center The Vis5D package can also be configured as a web browser helper application for UNIX-based workstations, and as a stand-alone Linix (unix) application on pentium-based PCs. We provide two examples below showing Postix pages for STELLA II and Vis5D files. Of course, the Postix digital poster concept is not limited to just these software packages.

Postix with Gif Image and STELLA II sample data download.
This Postix contains an image, description, reference, and a hyperlink to a downloadable datafile for a particular interactive modelling software package called STELLA II. The particular image shown here was made to simply identify this as a STELLA II example. Clicking the hyperlink either downloads a file named "...ozone.stm" for saving on your hard drive, or which launchs the STELLA II software directly if it has been purchased and established as a helper application. This particular STELLA II example is one included with the STELLA II software.

Postix with Gif Animation and Vis5D data download.
This Postix contains an animated Gif image which is a clickable hyperlink for downloading an advanced visualization datafile for an interactive visualization package called "Vis5D" developed at the Space Sciences and Engineering Center, University of Wisconsin. The animated Gif image in this Postix was made from images "grabbed" from the Vis5D visualization executing on an SGI workstation. If the image is clicked, the Vis5D datafile .../elnino.v5d is transferred across the network to your computer. If Wisconsin's Vis5D is configured as a helper application (as it is on our Unix-based workstations), the visualization will automatically launch just as with any other helper applications. Otherwise, you will need to arrange to save the data file on your hard drive for later use.

HOW TO PLAY Postix

1. All components of a Postix are immediately downloadable using a Web Browser. Thus, a single link to a particular Postix provides a convenient way to both: 2. You may make up your own Postix by, say, copying and modifying the relevant files in our examples, or by creating your own versions and styles. We hope that you adopt the general goals we propose.

3. To make your Postix materials available to others, you should then develop a directory of all of your offerings. An example of such a directory is the MARYLAND Postix Directory of Earth System Science Education materials we are using to archive our growing collection. Note that each entry in this directory is a Postix, and not the actual image or visualization file.

4. Such a Postix Directory can then be linked into a Directory of directories, and so forth. Interested organizations, such as the University Space Research Association Earth System Science Education Program might then maintain directories appropriate to the interests of their constituencies.

Oh by the way, if you like our Postix idea, then help promote it by adding the following link to your web pages. Feel free to also download the Postix animated logo.
<TABLE BORDER=1><TR><TD WIDTH=70 ALIGN=CENTER VALIGN=CENTER>
<A HREF="http://www.meto.umd.edu/~owen/POSTIX/">
<IMG SRC="http://www.meto.umd.edu/~owen/CHPI/postixan.gif"></A>
</TD><TD WIDTH=350><FONT SIZE=-1><B><I>
SINGLE-CONCEPT EDUCATIONAL MATERIALS<BR>
Gifs, Mpegs, Quicktime, AVI, VIS5D, gRADS,<BR>
Discussion text, Original Links, and Stuff<BR></I></B></FONT>
</TD></TR></TABLE>
Get Postix Animated Icon ...