mguhlin

Recording Video/Audio on Desktop on Linux


Earlier tonight, I had it in mind to record a BigMarker.com test session between Moodle Mayhem Podcast Co-host Diana Benner, Jen Hegna (our guest in October) and I. With the demise of LearnCentral.org, I began pursuing other options.


Simultaneously, BigMarker.com was kind enough to send an informational email sharing about their service. I proposed that they host the MoodleMayhem Podcast…they suggested I go get an account and give it a shot!

What do I think of BigMarker.com? It’s almost ready for prime time provided it handles somethings better, such as desktop sharing, faster refresh rate on its Java-based app. Aside from that, it has some nice features that are a boon for online learning facilitators that the LearnCentral.org crowd will certainly be missing in January. At this point, I recommend it for slideshow presentations, chat, a simple whiteboard, but no desktop sharing. 

I tried to record on my Mac using TechSmith’s Camtasia, but no cigar. I was using Soundflower–which allows you to record the audio output from your computer–but Camtasia was unable to accept the Soundflower as an input source, even though their Jing product can do so. Hmm.

So, what to do? How was I going to record my desktop, simultaneously capturing the audio, of Jen’s presentation? In desperation, I remembered that I’d played around successfully with gtk-recordmydesktop on UbuntuLinux.

Since I was running Peppermint Two linux, I decided to give it another shot:


Record Your Desktop – This is an UbuntuLinux friendly recorder (a few more here). To get it going, follow these steps:

    • sudo apt-get install gtk-recordmydesktop pavucontrol (creates OGV video format)
    • sudo aptitude install mencoder (this allows you to convert OGG to AVI video format)
    • Once installed, you can control it via a GUI interface or at the command line, type recordmydesktop then press Ctrl-C to stop it from recording.

The PAVUCONTROL program–Pulse Audio Volume Control–actually works like Soundflower in re-directing the audio flow to a virtual sound driver. You can do this on Mac with Soundflower (and HyperStudio has a proprietary virtual sound driver that works great) and on Windows.


While I was able to record my desktop, any part of it, the audio from BigMarker.com was not coming in. So, I setup PAVUCONTROL to be open and then clicked on ADVANCED button in recordMyDesktop (shown above).


In the DEVICE box, recordMyDesktop said DEFAULT. I changed that to pulse, as shown above, and audio started being included in the video stream.

This worked great! The file was saved as OGV, which can easily be converted using one of these sets of instructions (or just use WinFF but be sure to do this first):
  • Script to convert OGV to AVI
  • Use this command:
    mencoder -idx out.ogv -ovc lavc -oac mp3lame -o output.avi -srate 8000
  • Another bash script
  • Another command but using FFMPEG instead of mencoder:
    ffmpeg -i Your_Video.ogv -s qcif Your_new_Video.avi

Another neat feature of the Pulse Audio Volume Control tool is that while I was recording the desktop (video+audio), I am also to record directly to Audacity to get an “audio only” stream. Pretty nifty!

Nice tutorial online via YouTube on this whole process (not mine) that’s worth checking out!
On a related note, I played around with OpenShot Video Editor for Linux and was pleasantly surprised! Check out the screenshot:
I’ll have to spend some time playing with OpenShot in the future, but I’m hoping this solves video editing struggles folks have had on linux distros!

Get Blog Updates via Email!

Enter your email address:

Delivered by FeedBurner

Everything posted on Miguel Guhlin’s blogs/wikis are his personal opinion and do not necessarily represent the views of his employer(s) or its clients. Read Full Disclosure

Discover more from Another Think Coming

Subscribe to get the latest posts sent to your email.

2 comments

  2. QuickTime Pro now comes standard on Macs, and there is a wonderful screen capture tool as well as other featurs you may find very useful.

    Reply

Leave a comment