More and more students carry cellphones or laptops with video cameras built in, and many instructors are asking students to use them to turn in video homework assignments for courses covering highly visual material. New software developed at Purdue University seeks to make such experimental assignments easier to manage.
The system, called DoubleTake, lets students and professors shoot, share, and critique videos using a smartphone or a computer. One of the first classes to use it is one on sign language.
“There’s no way possible to do a written assignment in American sign language,” says Kyle D. Bowen, the university’s director of informatics.
It’s also being used in a criminal forensics course, where students capture themselves processing evidence as they would in a crime lab and then assess the performances as though they were defense attorneys.
Users upload raw video to the program, which connects with DiaGrid, a cluster of computers housed at Purdue. The computers then encode the video, converting it to a format that can be viewed within the system. Users are sent a link to the video and can opt to have the video shared automatically with an entire class.
Mr. Bowen says the whole process takes about five to seven minutes for a short video. The system can process multiple videos simultaneously because it finds computers in the cluster that are sitting idle to do the encoding.
Students can’t edit video within the program, but the system can accept edited videos from whatever outside program they choose to use, he says.
The program puts all submitted videos in one place, so that professors or other students can use a built-in scorecard to provide critiques, or grades, for each one.
The program also provides a key measure of security compared with commercial programs.
“The challenge with using YouTube is that it lacks privacy controls,” Mr. Bowen says. Videos uploaded to DoubleTake are only accessible within the Purdue community.
The program was developed over 10 weeks by one full-time programmer, one full-time designer, and another programmer who helped with the video encoding. The team created the browser-based program and an application for iPhones, and a student developer is working on a version for smartphones or tablets running the Android operating system. The videos can be incorporated into learning-management systems such as Blackboard or Sakai, and Mr. Bowen says his team is working to incorporate it into Mixable, a Purdue-specific social-networking application his team developed last year.
He says they hope to make the program available to other institutions and have already been in touch with a number of public schools in Indiana about bringing the program into classrooms there.
