Fast-forwarding through screencasts without ant voice

One thing that always stopped me from using screencasts as a viable learning tool is that they usually take too long. And most of the time it’s the guy moving around, or saying “uh”, “er…”, or doing stuff I already know. And when I tried skipping a few seconds ahead I usually skipped the very few meaty bits and had to go back and listen to them again. So what I did sometimes was increasing the playback speed (by pressing the ]-key on mplayer), but that made the guy speak as if breathing helium.

Not anymore!

Mplayer (from svn) has a fantastic new audio filter called scaletempo. It basically lets you change the playback speed without changing the sound pitch. The guy speaks faster, but in the same tone. Isn’t that amazing?! So, here’s how to do it (you really need the svn version as of now; 1.0rc2 won’t do it) on Ubuntu:

First, we need to install the dependencies for compiling the new package (without installing the package itself):

sudo apt-get build-dep mplayer

Now the usual checkout, compile and install:

cd /tmp
svn checkout svn://svn.mplayerhq.hu/mplayer/trunk mplayer
cd mplayer
./configure
make
sudo make install


And that’s it! Now you just open your videos like this:

mplayer screencast.ogm -af scaletempo

and use the keys [ and ] to adjust playback speed at will.

Edit: from my experience, you can speed up speech up to 1.5-1.75 without losing quality. That means you can watch a 1-hour video in 34-40min!

Learning Ruby (poignantly)

Since I started reading about web applications, next generation web, Web 2.0 or whatever you want to call it, I’ve been itching to get my hands dirty, go on and do something myself.

(When I say “do something” I mean getting a hang of the technological aspects involved in its implementation because, although the rest of the concept – social software, writeable web and all – interests me greatly, I’m sure not up for starting something up right now)

Bad thing is, I have no talent for design and my coding skills stop at some basic-level college C. And as I haven’t really decided to become a full-blown web developer all of a sudden, I think diving into HTML, CSS, Javascript, XML and all that would be a little too much to learn just to start playing around.

Then Ruby came to mind.

From what I’ve heard, Ruby is at once a great language for system administration – like Perl – and has that nifty Ruby on Rails framework for developing web software. And since I’m a loving Linux user and might get a kick out of getting a bit more into the server admin business, writing scripts and all, I thought I might get a good start at both (server admin and web dev) by learning Ruby.

That’s when I found this great, wacky and surprisingly fun tutorial: Why’s (Poignant) Guide to Ruby.

Ok, if you already know the basics of any other programming languages some things might feel a bit patronizing. And if you’re in a rush to learn it all very quick you’ll find it a bit dragging and miss the fun. But it’s sure a very entertaining read, it’s free (as in beer and speech), and besides giving you a good laugh (with cartoon foxes), it also actually teaches you the language.