Author Archives: Petar Mitrevski

Audio and video collaboration tools

Telepresence solutions
When considering audio and video collaboration tools (also known as telepresence) in education, the following technical factors should be taken into account:

– The scale of the collaboration: How many participants are expected to collaborate at the same time in a session?
– The nature of the collaboration: if there are more than two participants per session, are the participants going to be interacting synchronously or asynchronously? For three or more participants to interact face-to-face synchronously, the software must support multipoint connections.
– What devices will participants be using? PCs, Macs, stand-alone video conferencing units, regular phones, tablets, etc.
– Will content be added to the audio and the video? Do participants need to share their computer screen, a document, a video or music file?
– Does the collaboration software require a server-side component?
– What kind of bandwidth does the collaboration software need?

An educational institution can, for example, need 6-12 simultaneous video calls in a single conference, with a mixture of standalone video conferencing units, Mac and PC computers. At some point during this multipoint call, the presenter may want to show a powerpoint. On the backend, the institution may prefer to have the server-side components hosted offsite. Ideally, the licensing for this would concurrent.

Some examples of telepresence solutions that match and exceed these sample requirements: Polycom CMA, Vidyo Panorama, Microsoft Lync.

In addition, Nefsis is a competitor to the above, however it has no Mac support at this point.

It is worth noting that WebEx, with their Meeting Center product, can support a video conference with up to 7 simultaneous participants (any mixture of Macs and PCs). However, there is no support for connecting from a standalone video conferencing unit. Similarly, ooVoo supports up to 6 simultaneous participants (any mix of Macs and PCs) but, like WebEx, offers no support for connecting from a standalone video conferencing unit. If no document or desktop sharing is required, then ooVoo is free for up to 3 participants. To add up to 6 participants and add document/desktop sharing, there is some added cost.

Webinar solutions
At the same time, the institution may be interested in hosting webinars where face-to-face interaction is not required or desired. In such a situation, a solution such as WebEx may be best suited. It would allow a few people to act as presenters, while allowing hundreds or thousands to act as viewers. The biggest advantage of a webinar-style solution is that it is very cheap compared to a telepresence-style solution, can be used ad-hoc and allows almost anyone in the world to listen to the webinar without needing any internet connection.

Dell Driver Packages

My colleague discovered a wonderful page from Dell that provides nicely-packaged driver download links:
http://www.delltechcenter.com/page/dell+business+client+operating+system+deployment+-+the+.cab+files

$99 smartboard and Chief’s interactive mount

After Johnny Lee (Carnegie Mellon Grad) came up with his $99 Wiimote-based interactive surface, several industry solutions propped up as well. The latest one is from Chief (we use their projector mounts): combined short throw mount and mac/pc compatible interactive bundle that can turn any board into a smart board:
http://www.proavmagazine.com/mounts/chief-ships-interactive-mount-bundle.aspx?rssLink=042711-Chief+Ships+Interactive+Mount+Bundle

Microphone Feedback

Aside from the cell phone-caused speaker interference, there are additional sources of noise/interference in an audio system, including mic feedback. Here are some more resources that describe ways to reduce feedback:
http://toonz.ca/bose/wiki/index.php?title=Microphone_Feedback
http://www.google.com/search?q=mic+feedback
http://en.wikipedia.org/wiki/Audio_feedback#Directivity
http://www.mediacollege.com/audio/howto/feedback.html
http://www.audiocourses.com/article113.html
http://proavmagazine.com/acoustics/designing-a-mix-minus-distributed-sound-system.aspx
http://en.wikipedia.org/wiki/Microphone#Microphone_polar_patterns
http://www.ccisolutions.com/worshiptools/learn-about-microphone-feedback

http://www.shure.com/idc/groups/public/documents/webcontent/us_pro_mics_for_music_sound_ea.pdf
http://www.shurenotes.com/issue23/article.html
http://www.shurenotes.com/issue27/article.html

http://www.dt4u.com/dtsystems/feedback.php
http://boards.straightdope.com/sdmb/archive/index.php/t-34057.html
http://www.behringer.com/EN/Products/FBQ2496.aspx
http://www.mp3backingtrax.com/article56.htm