Frequently Asked Questions

about the NPAC/OLDA Visible Human Viewer

Note: If you have any questions about the Visible Human data set, or any biological/medical questions, please refer them to the Visible Human project at the National Library of Medicine.

I can't get the Visible Human viewer to run on my Web browser. What's the problem? Do I need to download a plug-in or something?

The NPAC/OLDA Visible Human viewer is a Java applet and can only be viewed using a Web browser that supports Java. Browsers with this capability include Netscape Navigator version 2.0 or higher, Microsoft Internet Explorer version 3.0 or higher, and Sun's HotJava browser.

You do not need to download any additional software or plug-in. If Java is working correctly on your Web browser, the Visible Human Viewer should work.

Note that some implementations of Netscape Navigator 2.0 do not support Java, for example for the Windows 3.1 operating system and for certain types of Macintosh computers. Java support is available for these platforms in Netscape Navigator 3.0 and later. This applet will not work with versions of Netscape older than 2.0 beta3, so you may need to download the latest version of Netscape.

If you are using the latest version of Netscape Navigator or Microsoft Internet Explorer and still cannot get the applet to work, first check to see whether you can view any other applets. If you can't, then you may need to configure your browser to enable Java. In Netscape 3.0, go to the Options pull-down menu, select Network Preferences and click the Languages tab, and make sure Enable Java is checked. In Netscape 2.0, check the Security Preferences in the Options menu. For Internet Explorer, check the Security options.

Accessing the applet from behind a firewall may possibly cause a problem.

If you still can't view the applet, it is probably due to a bug or inadequacy in the implementation of Java in the Web browser, which are beyond our control. You may need to use a different browser, or at least a different version of the browser. There are problems with some versions of Netscape, but the applet should work under Internet Explorer. Some of the known problems are listed later in the FAQ.

The applet runs, but when I try to download images, I get an error, or nothing happens. What's the problem?

For some versions of Netscape Navigator 4 the loading of images into the popup image slice window may not work in some cases - we are not sure why, but presumably it is a problem with the Java implementation. This problem does not seem to occur as often in version 4.03, and as far as we know does not occur at all with Netscape version 3 or Internet Explorer.

I get an error that the applet cannot be found, or that there is a security violation. What's the problem?

Pages displaying the Visible Human Viewer may use a remote codebase to access the Java applet, i.e. the applet is served by a different server than the Web page. In some cases, the server displaying the Web page may be up, but the server containing the applet may be down, so you may get an error message that the applet cannot be found. In this case you should just try again later. However some old versions of Netscape (notably version 3.0 for Windows NT) do not handle remote codebases correctly, which causes the applet to come up blank or give a spurious security violation. There may also be problems in some versions of Netscape Navigator Gold. In this case, we suggest you try other version (e.g. Netscape 3.01 or 2.0) or another browser (e.g. Internet Explorer).

This problems may also occur if you are accessing the page from behind a firewall.

The applet runs on my Web browser, but the display is all screwed up. What's the problem?

Some older versions of Netscape may have some display ordering problems, in particular the Windows 95 version of Netscape 2.0. If you encounter such problems, you may be able to fix them by clearing the Netscape cache. To do this, select the Options menu, the Network Preferences... item, and press Clear Memory Cache Now and Clear Disk Cache Now.

Netscape Navigator 3.0 beta and some versions of Netscape Navigator Gold also have problems. You should try to use the latest version, and perhaps try Navigator rather than Navigator Gold.

The applet starts up on my Web browser, but I can't see any images. What's the problem?

The applet uses JPEG compressed images. Some old Java implementations (notably Netscape 2.0 for the Mac) do not support JPEG compressed images. In that case, the applet may run, but you will not see any images. Try using a later version of the browser.

Is there a Visible Woman data set for the female body? How about other data such as MRI and CT images? Can you add these to your applet?

We have added the Visible Woman images in version 2 of the applet. We had planned to add MRI and CT images but we are no longer actively working on the Visible Human applet due to lack of funding. Check the National Library of Medicine Visible Human Project page for the latest news and information about the Visible Human data sets.

Can we use your applet or images for our project?

The Visible Human Viewer applet and images are freely available for non-commercial educational use (you can, for example, embed the applet in your Web page), as long as you credit us as the source of the applet and let us know what you are doing. However the applet and images may not be used for commercial purposes without our consent. If you wish to use many of the images, you may need to obtain a license from the U.S. National Library of Medicine Visible Human Project.

Your applet is really great, but wouldn't the user interface be much better if you did (substitute your suggestion here) instead?

The interface has a new look for version 2, with the buttons placed to the side of the images, rather than underneath. This fixes a problem with the old applet, that it was too tall to display the whole thing on 640x480 pixel monitors. We have made a number of changes to the original user interface to (hopefully) make it more intuitive and easier to use. Thanks to all the users who have contributed suggestions, especially Rick Rodgers from the National Library of Medicine. We have no plans to make further changes to the applet.

The NPAC/OLDA Visible Human Viewer, On-Line Data Archives Program.
Developed by Yuh-Jye (Michael) Chang, Paul Coddington and Karlie Hutchens.
Copyright 1995-97 NPAC and OLDA.
Send comments and suggestions to paulc@cs.adelaide.edu.au (but read the FAQ first!).
Last updated 20 Nov 1997.