By Joseph Labrecque


April 6, 2010

At the University of Denver, we’ve been using the Flex 4 framework for a number of smaller projects (over the course of the development of the new framework) and now that Flex 4 is final, we’ve also begun working it into our CourseMedia™ application.
The first tool to benefit from Flex 4 is our CourseMedia™ Arrangement Tool:
The old arrangement tool is actually a leftover from DUVAGA which was updated to work with DUVAGA2/CourseMedia™ when we made the transition to video and such a few years back. For the more technically curious; the old arranger was written in originally written in ActionScript 1.0 (!) and really requires an update for many, many reasons.
The new Arrangement Tool is built on the open source Flex 4 framework and users will immediately notice it to be much faster at processing information, making database calls, and soforth. We are actually rendering bitmap data from video feeds and text slides as well, while preserving the thumbnails created within CourseMedia. This will allow for much simpler item reuse in this tool and hopefully others down the road.
While grabbing the input frame for a video clip may seem to be the best idea, in our testing we noticed that many clips at the beginning of a film began with a series of black frames. This is obviously no good for thumbnail generation. What we decided was to determine the frame precisely between but the start and end frames for any given video clip and render that frame to be used as the video thumbnail as illustrated below.
Frame Calculator
Here is a functional overview video of the Gallery Arrangement Tool used in the University of Denver CourseMedia™ Course Media Management System: