Language Selection

English French German Italian Portuguese Spanish

Screencasting Under Linux--A brief Story

Filed under
Linux

My first consideration for making A/V screencasts under Linux is Software. What programs are available to do screen-recordings with simultaneous audio narration under Linux? I've probably tried them all: recordmydesktop (which has both gtk-recordmydesktop and qt-recordmydesktop GUI font ends), Istanbul, xvidcap, and wink. Frankly, none of these yielded the high-quality screen capture I wanted. But the real problem is that the audio quality was worse. After thrashing about, I finally end up with a non open source commercial product called DemoRecorder.

Now DemoRecorder is a commercial, proprietary program, which costs $47.00US, $77.00US, or $247.00US depending on the desired feature set. I purchased the $77.00 license. This does not work under Mandriva 2010 in nested desktop mode, but the openGL mode of capture works well. No dropped frames on the video side, and relativey smooth modion. On the audio side, no major sound glitches like I had with recordmydesktop.

Using DemoRecorder in the openGL mode is a two-phase process--Running the demorec --opengl program to perform the initial capture of the video and audio files, then the transcoding or assembly into a finished product using demorec-to-avi (or demorec-to-dv, demorec-to-flv, demorec-to-mpeg1, demorec-to-mpeg2, demorec-to-ogg-theora or whatever video codec/container you wish).

While the sound quality is considerably improved, it's still a bit hollow and tinny when recorded from my Logitech headset. I found the captured sound file produced by demorecorder, which I could then import into Audacity in raw format. I could then edit and improve the sound in Audacity, and export the edited sound file back to the drive before the assembly/transcoding of the video files and the sound file into one avi file.

This works--still, the sound isn't quite professional quality, but close. The real issue with this is that this type of post-production sound-editing takes a lot of time. Better, if possible, to get a high-quality sound recording to begin with, and bypass the editing step. Time for some research into sound production.

I have no experience in sound recording--I'm a computer guy, but I do like to play with hardware.
Fortunately, I already have a really good high-quality sound card in my working desktop computer--an HT Omega Claro Plus.

Turns out, you can get a decent quality mic, and a device called a sound mixer, and you can record really great sound. Good to know. I end up purchasing a Behringer XENYX 1204FX model mixer for $179.99US. This model of mixer turns out to be overkill on my part, and I now know I could have got by just fine with a cheaper mixer (prices for a mixer can range from $99.00US to several thousand US dollars).

As is often the case, one purchase often begets another. So, on to buy a decent, but relatively inexpensive condensor mike (after shelling out too many $$$ on the mixer). I end up purchasing an MXL 990 condenser microphone with a shock mount for $49.00US. Then a proLine desktop mic stand, model MS112 ($29.99US). Finally, I purchase assorted cables and adapters.

After all my sound gear arrives, I connect the mic to my mixer, the mixer to my sound card. Then I fire up Audacity to run some tests. After fiddling with the gear for about an hour, I'm amazed at the quality of the sound captures. Now I can start recording those educational screencasts in earnest.

More in Tux Machines

Most popular web browsers among Fedora users

Google Chrome is the most popular browser in the world. It is so popular that some call it a new Internet Explorer. But that’s based on global stats. In Red Hat, I’m responsible for web browsers, so I wondered what are the most popular web browsers among Fedora users. So I asked through Fedora accounts on Facebook and Google+: “Which browser do you use the most in Fedora?” Read more

Life in a Post-Container World and Why Linux Will Play a Diminished Role

Containers have actually been with us since the late 1990s, but they are not the end of the story. The real transformation will come with a “serverless” future that will completely overturn the ops ecosystem. Companies will go out of business, new ones will spring to life, and thousands of people will have fundamental changes to their jobs. The shift to a serverless future is much bigger than your normal hype cycle — I believe the current container hoopla is a foreshock preceding a 9.0 quake. Read more

FFmpeg's Leader Resigns, Hopes To Make Libav Developers Come Back

Michael Niedermayer, the leader of the FFmpeg project for the past eleven years, has made a surprise announcement today: he's resigning as its leader. Niedermayer is resigning as he no longer feels he's the best leader for FFmpeg, given the current Libav fork still persisting even after Debian dropped Libav and is returning to FFmpeg. Read more

30 Sys Admins to Follow on SysAdmin Day

Systems administrators: They keep our high-tech world up and running. From capacity planning, to 3 a.m. phone calls, to retiring that 10-year-old server that uses more power than your whole house, sys admins do it all. Open source communities would not be able to thrive without the networks, services, and tools that allow for communication and collaboration, and sys admins are the ones who work thanklessly year-round to keep them going. July 31 is System Administrator Appreciation Day, a day for all of us to express our undying gratitude for sys admins. Sure, you could buy your favorite sys admin cake and ice cream, or perhaps a nice gift card. You could even go as far as not breaking the server for just one day. You also can follow these 30 sys admins. Read more