My Educational Diatribe

This semester I have been screencasting my lectures for both first and second semester general chemistry. The students have loved it (comments and results from a poll will come soon) and they have used them as study tools as well as pre-lecture prep, without my even forcing it.

With each screencast, I was doing several things, each of which took some time…
1. Record the screencast
2. Produce the screencast into a flash file so I could post it on a ’streaming’ viewer for students who had slow connections.
3. Produce the screencast into a .mov file
4. Convert .mov file into .m4v file
5. Update the rss feed to iTunes music store so people could download .m4v file and watch on iPod or in iTunes

This took a lot of time, but I was trying to help two groups of students, those who wanted to download a local copy of the screencast and those who just wanted streaming video on the fly.

Then I found Google video, which allows me to post the .avi file to the mother Google servers. Many of the problems of the old method vanished:
- When watching the video, it ’streams’ like any other google video, which is good for slower internet speeds.
- Students can download it as an .mp4 video. It looks like Google did the conversion for me, a step that took me a while before.
- The search function works. I did a search for ‘jcc general chemistry’ and my screencasts popped up first. Also a search of ‘Ka Kw’ brought up my talk on acid and base dissociation constants. Very nice.
- I uploaded the full size version (1280 some odd pixels wide, 50 Mb in size) of the screencast and google shrunk it down to fit their size (the downloaded .mp4 file is 12 MB, for a 15 min screencast), which did not do much damage the image quality, and the file sizes are nice and small (fast loading, it took about 20 seconds to back-load my 14 minute screencast) Google converted it for me, they also shrank it (something I did before)
- No need for Camtasia ($$) at all. Camstudio (which is free!) produces .avi files that can be posted.
- Initial production time is cut way down because now I don’t have to ‘produce’ them at all. I uploaded the source file directly, let Google shrink and convert it.
- iTunes no longer needed. I can set up my own RSS feed for people to subscribe to.
- No local server space needed. These files are good sized (10-20 MB each) and I have lots of them. Now I don’t have to worry about space limits, as the files are on google.

Now, there are some bad sides:
- It takes a long (20-30 min each?) time to upload the files. I must say that I am uploading the behemoth ~50 .avi source files, however.
- It was ~36 hours from the time I loaded my first files onto the server until the video was ‘approved’ by google, so you can’t post stuff quickly. After I had loaded ~15 videos, I seem to have been ‘fast-tracked’, so now my submissions are approved much quicker.
- If you want to download a ‘windows/mac’ version of the video, you end up having to download the Goggle video player. You can not save it as an .avi or something else. You can download a .mov version that plays on a video iPod just fine (and other video compatible portable technologies in the future)
- No hope of password protecting the screencasts, although you can charge people to watch them.

Overall, I think this is fantastic. The negatives are minimized once you get a good set of videos up. It works for all people (those who want to download and those who want streaming)

You can also embed the google video right inot any webpage, including a blog, just like this:
My question is why the big guys (UC-Berkeley and MIT for example) produce their lecture videos is RealPlayer (.ram) format. Ick. You have to download a (questionable) player to view the files, and they are too big.

This entry was posted on Friday, February 24th, 2006 at 10:45 pm and is filed under Uncategorized. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.