I’ve known (and written about) MIT’s OpenCourseWare project for a while but never gone through any of the courses. I’ve found the first one I want to work through on Data Wrangling’s outstanding Hidden Video Courses in Math, Science, and Engineering page. One of the courses in the Mathematics header is Godel, Escher, Bach: A Mental Space Odyssey, and I decided to bite.
The book Godel, Escher, Bach: An Eternal Golden Braid, is widely praised as being an important, mind-bending, eye-opening book, but the reviews I’ve seen generally fall have fallen into two categories:
- people who have tried to read it but quit about 1/3 of the way through, but still proudly display it on their shelves as a badge of honor
- b) people who have read it and understand it, but don’t feel like trying to explain it to the uninitiated.
Since the MIT OCW course was a summer lecture series for high school students, I figured I could keep up. And by watching the lectures first, I’m hoping the book will be easier when I get around to reading it. It doesn’t seem like a book where I should worry about spoiling the ending.
There was one problem that took me a while to overcome: the lectures were in streaming .rm (Real Media) format. That means RealPlayer. I am not friends with RealPlayer – I cut my ties with Real in 2002 and vowed never to have their software on any of my computers again. If you don’t understand my revulsion, just Google “real player sucks” (477,000 hits).
So after a few days of tinkering, I came up with this solution for ripping rm streams and encoding them in a different format (I chose .mp4 so I can watch them on computer or video iPod). It takes about 20-25 mintues per hour of media but can be setup up in batches to run overnight. In my opinion, that’s a small price to avoid dealing with RealPlayer.
[NOTE: This is for Windows XP. YMMV on other platforms]
First, install these 3 programs:
- MPlayer – DON’T download the GUI version – you need the command line options to rip the stream.
- Real Alternative Lite – RealPlayer codecs without the player
- Free iPod Video Converter – there are zillions of programs that convert media files if you have the right codecs (it took me a while to figure that out) – this was the simplest, most straightforward one I came across
Second, rip the stream from the web. Open a Command window, go to the MPlayer directory, and type:
- mplayer -playlist [file URL] -dumpstream -dumpfile [destination file name]
This takes a while – streams download at 1-5x real time, so the 60 minute GEB lectures each took about 15-20 minutes each for me. Also, it doesn’t appear to be doing anything when it runs – it says something like “Cache set to 320KB”. It’s working, just walk away. You might be able to get multiple streams with one command by tweaking the command line args – let me know if you find something like it in the MPlayer documentation.
[EDIT: Apparently for MIT OCW streams, you can download them directly by changing the URL. Just change “ http://mfile.akamai.com/7870/rm/mitstorage.download.akamai.com/7870″ at the beginning of the streaming URL with “http://ocw.mit.edu/ans7870″. This way you can download them at full speed instead of streaming speed. Thanks Sharma!]
Third, once you have the ripped files, open Free iPod Video Converter, add the .rm files you ripped, and hit “Convert”. The defaults are fine – it sets video and audio quality based on the values in the source. This took about 5 minutes per hour on the MIT OCW files I used.
That’s it! Now instead of being tied to a computer with internet connection, you can take your learning on the go! Now go back to the Hidden Video Courses in Math, Science, and Engineering page and prepare for some seriously nerdly workouts!
UPDATE: My original streamdumps on a DSL line (~200K/sec) did not work right – the had correct file sizes but blacked out 50-70% of the way through. The mp4 conversions from those files just clipped off when the files blacked out. I tried downloading them using the direct downloads but the files got clipped and were only 30-40% of the expected file size. I tried the direct downloads when I had access to a T1 line and they all downloaded completely and played to the end. I’m not sure what the difference was, but check your .rm files to make sure they are the right size and play all the way to the end.