Cooking with Linux - Let Me Show You How It's Done with a Little Video
François, what are you doing still sitting in front of your computer? Our guests will be here any moment. Quoi? I appreciate, mon ami, that you are teaching your Aunt Marguerite to use Linux, but must you do it in real time over a VNC control session? Of course there are other ways, mon ami. For instance, you could create instructional videos, screencasts, and e-mail them to her. Yes, I would be happy to show you how, but for now, you must say Au revoir to your aunt and log off. I can see our guests coming up the walkway now.
Welcome everyone, to Chez Marcel, where great Linux and open-source software meets great wine, and of course, great people. C'est fantastique to see you all here tonight. Please, sit and make yourselves comfortable. François! To the wine cellar, mon ami. Bring back the 2003 Château Maris Minervois Old Vine Grenache from the south wing. I remember seeing a half-dozen cases there.
Before you arrived, mes amis, François and I were discussing approaches for showing people how to use various software packages, perhaps for teaching a friend or relative how to use a Linux desktop. I suggested that rather than resorting to remote control sessions, it might be more efficient to create small training videos and use those instead. Besides, instead of reaching one person, this way you could reach many. This is popularly referred to as screencasting. Creating screencasts doesn't have to be difficult, and the features on tonight's menu will have you creating your own in no time.
The first program I'd like to show you is Zaheer Abbas Merali's Istanbul, a screen recording program that sits quietly in your system tray, waiting to be called on. The program is available from live.gnome.org/Istanbul. Source (both stable and development) is available from the Istanbul site as well as Debian packages. And, packages for other distributions are easily located, for example, at rpmfind.net.
To start Istanbul, simply run the command name, istanbul. When you do, a small red icon appears in the system tray. Right-click on the system tray icon (a small red circle at this point), and a small pop-up menu appears (Figure 1). From here, you can make a number of changes in Istanbul's default recording. For instance, you may choose to make a smaller recording by selecting half width and height instead of full size. You also can choose to record your entire desktop or select a specific area to record. If you do the latter, Istanbul provides you with a large X cursor that you can drag around the area you want to record.
I should alert you to one other very important point, mostly because I scratched my head for some time on this one. Notice that there is also a selection labeled Record Sound. You need to enable that if you want to add sound to a screencast.
As I was writing this article, the Istanbul development package also gave the option of selecting an active window, usually an easier choice than selecting an area for recording.
To start recording, simply click the red button. It changes to a gray square while you record your session. Talk clearly into your microphone and demonstrate the steps in the window you selected as you explain the process. When you are done recording, click the gray button. A dialog labeled Save Screencast appears (Figure 2).
On the left-hand side of that dialog, there's a preview window showing your captured video. To preview it before saving it, click the Play button below the preview window. On the top left, you can enter a file for your video and select a folder in which to save it. As you might have guessed from the save dialog, this is a GNOME application, but it works very well under KDE also.
Note that Istanbul saves in OGG format, so if you want something else, you have to convert it after the fact using a program like FFmpeg or mencoder. Many Linux distributions come with a copy of FFmpeg or provide it on their repositories. Using it is pretty simple. For instance, to convert an OGG video to an AVI file, you might use this command:
ffmpeg -i recording.ogg newrecording.avi
As you might expect, there's a lot more to the program, but it can be this simple. For a whole lot more on FFmpeg, check your on-line documentation.
Practical Task Scheduling Deployment
July 20, 2016 12:00 pm CDT
One of the best things about the UNIX environment (aside from being stable and efficient) is the vast array of software tools available to help you do your job. Traditionally, a UNIX tool does only one thing, but does that one thing very well. For example, grep is very easy to use and can search vast amounts of data quickly. The find tool can find a particular file or files based on all kinds of criteria. It's pretty easy to string these tools together to build even more powerful tools, such as a tool that finds all of the .log files in the /home directory and searches each one for a particular entry. This erector-set mentality allows UNIX system administrators to seem to always have the right tool for the job.
Cron traditionally has been considered another such a tool for job scheduling, but is it enough? This webinar considers that very question. The first part builds on a previous Geek Guide, Beyond Cron, and briefly describes how to know when it might be time to consider upgrading your job scheduling infrastructure. The second part presents an actual planning and implementation framework.
Join Linux Journal's Mike Diehl and Pat Cameron of Help Systems.
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With all the industry talk about the benefits of Linux on Power and all the performance advantages offered by its open architecture, you may be considering a move in that direction. If you are thinking about analytics, big data and cloud computing, you would be right to evaluate Power. The idea of using commodity x86 hardware and replacing it every three years is an outdated cost model. It doesn’t consider the total cost of ownership, and it doesn’t consider the advantage of real processing power, high-availability and multithreading like a demon.
This ebook takes a look at some of the practical applications of the Linux on Power platform and ways you might bring all the performance power of this open architecture to bear for your organization. There are no smoke and mirrors here—just hard, cold, empirical evidence provided by independent sources. I also consider some innovative ways Linux on Power will be used in the future.Get the Guide