Distance learning applications can now make use of networked computers to transmit and display video, audio, and graphics. However, desktop video conferencing systems (DVC) often display degraded images due to bandwidth restrictions and computer processing limitations. The literature on the influence of video parameters such as frame rate and resolution with respect to subjective opinions and human performance is sparse. A two-part study involving a controlled laboratory experiment and a field study evaluation was conducted on technical parameters affecting the suitability of DVC for distance learning. In the laboratory study, three frame rate conditions (1, 6, and 30 frames per second), two resolution conditions (160 X 120 and 320 X 240), and three communication channel conditions were manipulated. Dependent measures included performance on a quiz and subjective satisfaction with the image quality. Results suggest that quiz performance does not suffer under reduced video quality conditions, but subjective satisfaction significantly decreases. The field study employed similar dependent measures and indicates that students in real classroom situations may be less critical of poor video quality than in laboratory settings and confirms the results from the laboratory study in that performance does not suffer. However, the current state-of-the-art of video conferencing technology needs to be improved and configured most effectively to support college teaching at a distance. Guidelines for implementing and using DVC systems in distance learning applications are provided.
All Science Journal Classification (ASJC) codes
- Computer Science(all)