Instructions for Applets

This page explains how to use the applets and scripts available on this web site.

TrackApplet

The TrackApplet is used to review tracking data. It loads a background image (if available) and some tracking data. Using the controls available below the viewing area, you can review the tracking data in many different formats, sort the data, and run simple queries. Unfortunately, this applet is still under development so this page will probably lag behind.

WARNING! The applet will begin to display the data before it has finished loading. It will perform much better after all the data is loaded. Also, there are no guarrantees on queries and sorting performed before the loading has completed. The black dot in the lower right corner will disappear when loading is complete.

Image of Applet

	The ViewPanel and InfoPanel

The left panel is where the tracking data is "replayed." The right panel displays information about the currently displayed tracking data. In some browsers, the InfoPanel will not update at the same rate that the ViewPanel updates. The information displayed includes the date, time, uniqueID, score (see Sorting Controls below), and size.

	Playback Control

Although these controls are somewhat crude, they are similar to standard VCR controls. Dragging the slider will allow you to quickly review the tracking data.

"|<" Rewind to first frame or first sequence.
"<<" Skip to the beginning of the previous sequence.
"<" Play backward.
"0" Stop.
">" Play forward.
">>" Skip to the beginning of the next sequence.
">!" Full forward to the end of the last frame or sequence.

	Drawing Mode Selection

The three choice boxes determine the representation of the object which is drawn, where that object is drawn, and what is used as the background, respectively. The casual user will be best served by using the mode button to select from a number of preset drawing modes.

	Applet Sorting and Querying Controls

The left choice box allows you to sort the data. In "FrmByFrm" mode the data is played back in chronological order. The other modes order each tracking sequences and allow them to be played back in that order. The filter button filters out tracking sequences which are extremely short or don't move anywhere on the screen. The find button returns the the last object that was clicked by the user. The query button is not fully functional. Currently it orders the objects based on their similarity in color to the selected object.

I apologize for the lack of intuitive interface. Unfortunately, this is not at the top of our "things to do" list at this point. We'll do our best to put the new tools on the page as they become available.