Dear all
I saw the 1st media dissemination event recordings made by Switch, they are of excellent quality. By watching these recordings I could go over topics of my interest once again. Many thanks to Switch and Terena for organizing and recording this workshop.
I would like in this post to introduce some features of the Tel Aviv University (TAU ) solution for academic lecture recording.
p>Our first attempt to record a lecturer's video and his desktop was made some 4 years ago. At that time we developed a Javascript based procedure to synchronize between two video streams on a single web page. The streaming technology was Microsoft Windows Media 9. We made several hundred recording hours using this technology.
Sample recording link using this format (works only on Microsoft Internet Explorer):
http://video.tau.ac.il/General/Computing_Division/microsoft/sp2M/sp2M2.htm
We eventually stopped using this double stream format due to synchronization problems under poor network conditions (at that time, 3 years ago, the Internet infrastructure was not developed enough). I am very much impressed now by Flash media streaming performance. Had this technology been available at the time, I would have kept on trying to improve our double stream solution.
In the process of seeking a solution that will deal in a better way with poor network infrastructure we established a recording method that combines two video streams (lecturer's video and his desktop activity) in a very simple way without the need for even a single line of code.
http://video.tau.ac.il/Lectures/demo/orna1.html
Using this combined stream format we have already recorded over 5000 hours of lectures.
Advantages of the format
- The sync between the lectures video and his desktop is absolute and is not effected in any way from the network conditions
- Optimal usage of the display area 3 by 2 data/ image ratio (no unused area is left on the wide display mode)
- Can run on a PDA, displaying lecture's video and his desktop screen capture.
- Can be easily transcoded to any media format.
- High screen capture rate (up to 20 frames per second).
- Recording of full frame rate videos presented on lecturer's computer (under optimal conditions).
- Works Under Microsoft Windows Media technology (indexed access works only for Microsoft IE)
- Lecturer's video and his desktop screen capture display ratio is defined during the recording and can't be changed by the user.
We are seeking partners to work with on implementing this recording format to Flash based streaming.
