IBM Transcoding Proxy Demonstration

The IBM transcoding proxy integrates both image and text transcoding into an HTTP proxy.  To see how Web pages can be transcoded by our proxy, follow the two-step instructions below.  The figure below shows that you will need to configure your browser to access the Web through our proxy.

Instructions:

I. Configure your browser to point at our proxy

1. If you are using a Netscape 4.x browser, set the browser to access the Web through the  proxy as follows:
1. Pull down the Edit menu,
2. Click on Preferences.  You should see a window similar to what we have shown below.
3. Expand the Advanced category (double-click on Advanced)
4. Click on Proxies
5. Push the Manual proxy configuration button and then click on View.  You should see  a window as shown below.
6. On the HTTP: line, enter either the number 128.59.66.93 or the name  anasazi.ctr.columbia.edu under "Address of proxy server to use", then tab over  to Port and enter 8080.
7. Click on OK
8. Click on OK
2. If you are using an Internet Explorer 3.x browser, then pull down the View menu, click  on Options, click on the Connection tab, then click on the box "Connect through a  proxy server" and in the line for HTTP: enter 128.59.66.93 for the proxy address and  8080 for the port.  Click OK to finish.
3. If you are using an Internet Explorer 4.x browser, then pull down the View menu, click  on Internet Options, click on the Connection tab, click on the box "Access the  Internet using a proxy server", then click the "Advanced..." button and in  the line for HTTP: enter 128.59.66.93 for the proxy address and 8080 for the port.    Click OK twice to finish.

II. Control and adjust the proxy's degree of image compression/speed of download:

We provide three ways for you to specify your transcoding preferences to the transcoding proxy concerning how much compression should be performed on images:

JAVA Applet GUI (Please also consult the FAQ page):

1. A Java applet containing a slidebar allows the user to control  the tradeoff between download time and image quality.  The slidebar  conveys  your transcoding preferences to the proxy.  The highest slidebar level corresponds to  aggressive compression and fastest download, though the resulting image will have the  poorest quality.  The lowest slidebar level corresponds to the lightest compression  and slowest download, and the resulting image will have the highest quality. 
2. To install the Java slidebar interface:
1. Enable Java in your browser.
1. In Netscape 4.x, go to the Edit menu, click on Preferences, then click on Advanced, and  click the box that says "Enable Java".  Click OK to finish.
2. In Internet Explorer 3.x, pull down the View menu, click on Options.  Click the  Advanced tab.  Click on the box that says "Enable Java JIT compiler".   Click OK to finish.
3. In IE 4.x, pull down the View menu, click on Internet Options.   Click the Advanced  tab.  Scroll down and click on the box for "Java JIT compiler  enabled".  Click OK to finish.
2. Invoke  this Java applet or download  the applet before opening/running it locally.
3. The Java applet will work best with Netscape.  Earlier Netscape releases, e.g. 4.03 and 4.04, require the JDK 1.1 patch, while a  special build of 4.05 already includes the JDK 1.1 patch as one complete install.  If  you have Netscape 4.5 and above, then JDK should already be built into the browser.
4. Move the slidebar to the desired level of transcoding.  Hit the Apply button after  you have set the slidebar.  Your preferences to the proxy will then be sent to the  proxy.   You will receive an acknowledgment message indicating that your preferences  have been set. Your preferences apply to all of the images that you receive and remain in  affect until you change them.  Click on the Color checkbox  to toggle between  receiving grayscale images and color images.  Typically, grayscale images are about  2/3 the size of color images. If the box is not checked then you will receive your images  transcoded into grayscale.  Settings are not registered at the proxy until you push  the Apply button.

HTML GUI:

For those cases where you are using a browser that doesn't support Java  or where your resources are limited, we have developed an HTML-only interface. We have a  web page that gives you the following four choices:

• You may invoke  this HTML-only interface, though it's limited to gray-scale transcoding.

Low-level GUI:

Manually enter a URL of the form http://artour.web.express/image/N,  where N is a number between 0 and 19, e.g. http://artour.web.express/image/5.   This magic URL will be intercepted by our proxy to set the user transcoding preferences.    Numbers between 0 and 9 indicates the degree of quality reduction (i.e., download  speed-up) that you desire for grayscale mode. Zero indicates no transcoding (the default)  while 1 is the least compression/slowest download and 9 is the most compression/fastest  download. Consequently, a setting of 9 should result in a faster download than a setting  of 4. Numbers from 10 to 19 correspond to the same degree of image quality reduction  (based on the value of x in 1x) as the range from 0 to 9 except that this range will  maintain color.

Text Transcoding

• The IBM transcoding proxy includes text transcoding in addition to image transcoding. As  with images, we provide different levels of text transcoding. The text-enhanced Java  applet slidebar has the following appearance:
• Text transformation may cause a page to look very different from the original page. For  example, in one of the transformations we remove Java Script. This may affect the  rendering of the page by the browser.  The Java applet may be  invoked  here.
• Just as for images, you may manually enter a URL to control text transcoding:    http://artour.web.express/text/N, where N is a number between 0 and 9. Zero  indicates no transcoding while 1 is the least and 9 the most.