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Casual Programming and Linux Screen-Recorders

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After being retired (for four years) from teaching high school Computer Science, I decided to get back into programming again. I once taught a beginning programming class using the Ruby language, and I thought that would be a good way to get back into programming. So, I decided I needed a “Ruby refresher”, and I wanted to learn more about that language than I taught in the classroom.

After much surfing and sampling Ruby instructional videos online, I finally purchased Pragmatic Studio's Ruby Programming Video Course. Note that this course is not free--in fact, it's $199 US. But it includes a vast amount of material.

There are 25 videos covering everything from Numbers and Strings to Objects to Project Distribution. Better yet, the videos are HD in quality, and DRM free. So once registered, you can download all 25, and utilize them at your convenience. The total duration is nearly 5 hours, but since the videos are only 5-20 minutes each, you can work through the course in small increments. They are well put-together, follow a step-by-step sequence, vocally clear, and well done.

In addition, you get access to an online workbook that leads you through implementing a project similar to the one shown in the video lessons. Nearly every video has a corresponding workbook lesson, so you get to practice using the new concepts. Here's the Video Lesson Topic Outline (Items 1 & 13 each contain 2 videos):
01. Introduction(2 vids)  10. Objects Interacting  19. Input/Output
02. Running Ruby          11. Separate Souce Files 20. Inheritance
03. Numbers and Strings   12. Unit Testing         21. Mixins
04. Variables and Objects 13. Conditionals&TDD(2)  22. Distribution
05. Self                  14. Modules              23. Wrap Up
06. Methods               15. Blocks
07. Classes               16. Symbol and Structs
08. Attributes            17. Hashes
09. Arrays                18. Custom Iterators
So, yes, a sharp price—but with sharp instruction.

Making my Own Videos
Now, the quality videos from Pragmatic have inspired me to start making quality instructional videos. Again, after searching high and low for a good screen recorder, I finally chose another costly program: Demorecorder.

Yes, this program too is costly, but gives me the high-quality video and very-high quality audio that I'm looking for. There are differing levels of the program you can purchase:

  • DemoRecorder-Pro (node-locked license) – $247.00 (Volume Discounts Available)
    DemoRecorder Pro is for professional users who also create full screen recordings and who need premium support. (It is not intended for unattended long term recording of system usage. In that case please purchase the 24/7 edition)

  • DemoRecorder-24/7 (node-locked license) copy – $997.00
    DemoRecorder for long term recording for logging and documentation purposes of (mission critical) systems. (This edition not yet been officially released...but available in purchase preview edition).

  • DemoRecorder-Web (node-locked license) – $137.00 (Volume Discounts Available)
    For amateur user who also wants to show the videos on the Web using streaming with Flash technology. (And who does not need premium support, i.e., can wait longer for getting support queries answered.)

  • DemoRecorder-Standard (node-locked license) – $97.001 (Volume Discounts Available)
    For amateur user who does not need export to Flash Video. (And who does not need premium support, i.e., can wait longer for getting support queries answered.)

Now, considering the cost of Camtasia ($300 US), which is the best screen recorder available under Microsoft Windows, the prices seem reasonable. And DemoRecorder-Pro (or better) provides the capability of creating videos in the following formats: AVI, MPEG2, MPEG4, VOB, FLV, and FLV+SWF+HTML for video-streaming over the web.

Yes, I've tried several free screen-recorders in linux such as: recorditnow, kazam, Istanbul, and recordmydesktop. I'm using very good quality video cards, graphic cards, and good system throughput. The only one which gives me the quality I seek is DemoRecorder.

So, yes, I use a costly screen-recorder. But I do use FLOSS as well. I edit the video clips with kdenlive, use Libreoffice Impress for some presentations, gimp and mtpaint for drawing, and the codeblocks Integrated Development Environment and Geany text-editor for programming demonstrations.

I hope to have some material to present in 3 or 4 months.

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Best recorder ffmpeg/avconv

I found that an avconv (ffmpeg) command with a carefully selected set of parameters can produce perfect quality screen recordings on high resoltion outputs even on my old core 2 duo directly encoding with h264. I don't have the command at hand right now, but leave a message if you are curious and I'll be back with this free solution.

I would be very interested in

I would be very interested in this.

Video was OK--audio was the problem

In terms of Screen Recorders, most videos were adequate--the big issue was the audio quality.

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