An Inexpensive Method for Recording Lectures Without Use of a Video Recorder
Comparison with Other Methods
Most streaming chemistry lectures currently viewable on the web are captured using conventional video and audio recording equipment [1]. These require a support staff to operate cameras, sound recorders, lighting, etc., but the result can be effective. Most lecture halls, however, are not optimal for such recording, with audience noise and student movement as examples of various distractions that can occur. Processing the resulting media for streaming is demanding in both effort and time. Although AV studios are available on our campus, they are not large enough for freshman chemistry classes. Since we lacked the resources for conducting conventional recording in class, we sought other recording methods.
One method that we considered was developed by Craddock and Mendrela employing an inexpensive webcam, coupled with an electronic whiteboard and a microphone connected to a PC laptop computer [9]. The webcam video signal is electronically combined and synchronized with the whiteboard and microphone outputs using a software application that feeds a Real Streaming Server©. The method is relatively inexpensive, except for the whiteboard, but it has two important disadvantages. First, even though the authors sought to create a system that required “zero-effort” on the part of the lecturer, we saw set up and take down as troublesome. Second, the quality of the webcam video was too marginal to justify the bandwidth it consumed.
Before developing the method described here, we used a PC-based recording system that incorporated a special video card and an external hardware scan converter and microphone mixer [10]. In this system, a special software interface allowed live streaming of lectures that were also archived for on-demand viewing. In this system, however, only a relatively small “live” window could be provided because the effectiveness of file compression was limited. This method had the advantage that messages and a (static) picture of the presenter could be included in the unused part of the window that was streamed. The main disadvantage was that the initial cost of the system was increased by over $4000 for the extra hardware. The lecturer also had more equipment to deal with and the level of IT staff support needed was greater than the current method.