VideoPoint Features VideoPoint allows you to gather position vs. time data for one or more objects on each frame of a QuickTime movie. This data can be plotted, viewed in a table, copied to other programs (such as MathCad and Excel) for further analysis or modeled using basic equations or fit to a polynomial. VideoPoint's strength is in the collection of this data; combinations of the locations of points can be used to create other measurements such as Center of Mass locations and Distance measurements. Point Series The point series is the basis for data collection in VideoPoint. A single Point Series can be used to track the location of a feature or object of interest for each frame of a movie. For example, if you were looking at a two-puck collision, you would create two point series, named Puck1 and Puck2 and click on the location of Puck1 when Puck1 is selected, and on the location of Puck2 when Puck2 is selected. The locations are stored for each frame of the movie (hence the name 'series') You can have as many Point Series as you need. Each point series can have a different marker, mass, trails, visibilty and name. The distance series is the simplest calculation based on two points. It simply reports the distance between two point series. You can specify any two point series for this calculation. The Center of Mass series calculates the mass center for a set of point series based on the location and mass of each point included. You can include as many points in this calculation as you need; this is nice when calculating the center of mass of complicated systems such as the human body. The scale series is the basis for scaling movies from screen coordinates (pixels) to real units (e.g. meters) by determining a scale factor (pixels/meter). Most scaling is done through an easy process of anserwing a couple questions and locating the ends of an object of known length on the movie screen. The Scale Series is flexible enough, however, to accomodate for zooming cameras (in which the scale factor changes on every frame!). Creates a designated point series. Each designated point is located relative to the locations of two other video points on each frame. A designated point can have a relative displacemnt along the line connecting the two points as well as a relative displacemant perpenducular to the line between the two points. Reports the angle between the lines connecting two video points on a frame to a third video point wich is designated as a vertex. Creates a video point series identical to that of the selected video point series. Cloning a video point series allows you to determine positions for a video point series relative to two different coordinate systems.
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