Video Analysis

To analyze a video using Logger Pro:

NOTE: Hover over buttons to see the name of the button. If you get stuck and don't know how to do something, there are much more detailed instructions in the included Help file.

-Go to the top menus, and choose "Insert", "Movie". The movie will appear in a window within a window. Video analysis features are on this window.

-Click on "Enable/Disable video analysis"

-"Set Scale" to scale the movie (click on the button shaped like a ruler)

-Click on "Add Point" and set your points.  Choose the same part of the object each time. Graphs are generated automatically. 

-Use "Transform Axes" to move and rotate the x-y axis, if necessary. Both horizontal dimension ("X") and vertical dimension ("Y") graphs are generated automatically. Examine the graphs to decide if transforming the axes will simplify your data.

-Perform a curve fit on any of the graphs, depending on what you need.


Tips for Collecting Video for Analysis

-The camera should not move or pan.

-The camera should not zoom.

-Use a tripod.

-Include an object of known length as near as possible to the action.

-If possible, choose a contrasting background (whiteboard or blackboard works well).

-Keep the plane of the action parallel to the plane of the camera sensor.

-Make your video as short as possible.

-If you make a video and have trouble marking the object, using masking tape or paint on the object to make it show up better sometimes helps.

-High-speed cameras are relatively inexpensive.  If you want to do a lot of video analysis, consider buying one of them.

-Bright light helps. Use extra illumination, if possible.

-Choose an object with contrasting colors or put white or black tape on the object to make sure there is something easy to mark when you set your points.


Popular Video Analysis Tools


*Logger Pro

Video analysis is built into Logger Pro from Vernier (http://www.vernier.com). Logger Pro is about $180 for a site and home license (your students can install the program on their home computer). They also sell an iPhone and iPad app, Video Physics.


*LivePhoto

There are movies for video analysis, some with embedded tools (you don't need a separate program, just a web browser) at the LivePhoto Physics Project (http://livephoto.rit.edu).


*Tracker

Tracker (http://www.cabrillo.edu/~dbrown/tracker/) is a free video analysis program that is very powerful and runs on mac, windows, or linux.  It can also be run from the web, without installing anything.

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