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Microphone

Summary: How to make Internet-based phonecalls and also record them with Free software and open standards

TECHBYTES has had to do some research into recording shows with Free software. It was actually our intention since the early days of the show (November 2010) to look into a pipeline which is entirely Free software based. Because of convenience or laziness, we settled for and ended up recording the show under Skype, then doing the rest with Free software. We actually started by experimenting with SIP to some extent while simultaneously looking into a recorder which was compatible with Skype for GNU/Linux. As the show involved many guests (especially at the start) we needed to facilitate Skype access and curtailed the pursuit for a SIP replacement until more recently. Then came the time to record with Richard Stallman, which coincided with the disturbing rumour that Facebook would buy Skype. Eventually it was Microsoft, which can be seen as equally bad.

This post summarises my findings and to some extent Tim’s observations too. We spent many long hours researching the subject, testing many packages, testing the process inside many calls, and making a lot of test recordings, then refining them and adjusting parameters including volume levels. Some listeners provided valuable advice. Some gave application recommendations and here is what was found after a fairly thorough exploration.

SIP Communicator

I started using sip-communicator after Gordon Forbes had made the recommendation (about 4 months ago). It is pretty impressive, it is very features-heavy, and it was built with Java, which makes it somewhat heavy too. The version I use is still not very polished. It has some debugging-level code in it. The good thing about it is the built-in recording capability, webcam support (which works well, unlike Skype which never ever worked for me with any webcam), and automatic detection of all the underlying hardware. It worked with my webcam over the network, but not so consistently though. Some buttons seem to not yet have a callback function associated with them, at least in the version I have installed. It is like a development build. But, having said that, it’s a decent cross-platform application with good SIP support, assuming it can connect to the other side successfully.

Linphone

This good client does not appear to support video although Tim claims otherwise and my experience with it is very limited (the binary to run is linphone-3 on *buntu-based systems, not linphone) . It did not quite succeed with the callers I tested it with. It does have echo cancellation, just like Ekiga, which is the main application that I use.

Ekiga

So, that brings me to Ekiga. Fine application, although the toolkit it uses for the UI does not integrate so beautifully into KDE4. Even Skype sorted that out not so long ago (Qt Curve added), but Skype is out of the question here. Ekiga does everything, including video, reasonably well. Its Windows version is not so official however. When it comes to camera support, it does not consistently transport the image to the other side. Sometimes it works, sometimes it does not, for whatever reason. It worked for us with webcam over the network, but most of the time it does not.

Blink

One listener told me about Blink, which is cross-platform and quite good looking. It is abundantly easy to use. I have not had so much time to test it, having installed it from unofficially-approved repositories (quite successfully and without issues though). Its cross-platform support seems like a big advantage considering the fact that Ekiga may not support a lot of platforms reliably. Maybe the Skype exodus will motivate developers to hurry up with such development endeavours. Telephony is one of those areas where multiple sides are involved, so ports to proprietary platforms can be more easily justified.

Mumble

For a call with multiple participants this piece of software can be handy. it is cross-platform, it has wonderful setup wizards, and it is easy to use. We may use it in the future. Asterisk has a reputation of something that is hard to set up for similar tasks. Based on TLLTS, there are also recording quality issues associated with it. This downsamples everyone on the line. Of course, it is always possible to record separately on each side and then merge everything. But this is time-consuming and it requires manual synchronisation work.

Left out from this survey we have lots of GNU-affiliated packages and we of course do not bother with so-called ‘Cloud’ Computing options from Google (or Gizmo), which is Fog Computing and proprietary. It’s hardly better than Skype in that regard, as both are cross-platform.

Recording

Recording is another important part of the pipeline. As an alternative to Skype Call Recorder (which works with GNU/Linux) we considered using SIP Communicator and later Blink, which we were told has some recording facility. We have not found that in the GNU/Linux version yet. In any case, recording all system sounds from PCM seemed reasonable and alsamixer enables this to be done at some lower level, if not other mixers that are graphical. Failing to attain high quality, we may just record locally and then merge at the end, as Linux Outlaws is doing for example.

Audacity

Here are some instructions on how to get things working with Audacity. It may not work on all systems and filters might be needed to compensate for noise. But still, it is better than nothing. Since Audacity is also our editor of choice, integration of this sort is desirable.

GTK RecordMyDesktop

The package gtk-recordmydesktop is a front end to a program which requires some command-line-fu. The settings in the GUI are easy to follow and there are detailed tooltips too (optional). For additional command line options such as strict coordinates from which to capture can be specified in the GUI too, if necessary. Those who developed the product did a fine job simplifying screencasts, which is essentially how we process video-based shows. Encoding can be done at the end of recording in order to lower CPU load, especially if compression is used to compact large videos that are mostly static throughout.

Editing

For editing we have only used Audacity with a bunch of filters that we know help improve the quality of raw audio. The program is good for mixing several tracks, Except for that, my only prolonged editing experience goes back to Windows 3.11 days with Sound Blaster software. As I was about 11 or 12 at the time, that does not count for much. We are still improving and since we never edit any of the speech part (not even editing out or having second takes, the editing is mostly mixing oriented).

Encoding

To re-encode videos we use mencoder and ffmpeg, which are command line utilities that do the job pretty well. Some reasonable commands that we routinely run are gathered in a text files.

Postscript: Tim says that Linphone supports cameras and this Wikipedia page, sent by a reader while working on this text, might be handy.

Regarding phone books management, some applications were simpler to manage than others. My personal choice is Ekiga’s, which also has a complete historical calls trail. It is very useful.

If we left out important options, be sure to tell us.

GNU Octave a Compatible Drop-in Replacement for MATLAB

Over the past couple of months I have been assessing the combination of Octave with some other free/libre software such as Scilab and QtOctave. I did this as part of my existing job in research, as my blog posts ought to have revealed on occasions. I’ve been using MATLAB for the best part of a decade and was at one time ranked #1 in the world for my contributions to MATLAB Central. That, however, changed several years ago when I came to grips with the fact that my free/libre code for MATLAB only helped promote the underlying stack which included MATLAB, a nasty piece of highly expensive proprietary software with BSA bullies behind it. MathWorks is exploiting free labour of many people to sell its non-free software. I can vividly recall Slashdot comments stressing this point, which profoundly changed my attitude towards MATLAB. So I turned to Octave, as I did half a decade ago, but this time it was a lot more mature. People recommended to me programs other than Octave, too. I checked these under different distributions of GNU/Linux and even Windows, which many people out there continue to use, especially on their desktop. I helped some people dump MATLAB. I saw how easy it was.

MATLAB is used extensively in research and in the industry, sometimes even in hospitals (when I was 22 I was asked to help a professor with that). In many cases, it boasts more features than anyone would ever need*. Does a university student really ever use more than the basic functions? Are companies really willing to spend thousands of dollars per year just ‘renting’ a licence for one or two copies of MATLAB, which keeps nagging them for it assumes they are so-called ‘pirates’ (and the BSA comes knocking to ensure there are up-to-date licensing instances)? The answer is usually “no”, but users of MATLAB may not know that software already exists to offer them an alternative, just as Firefox helps replace Internet Explorer and also outperform it in many technical ways. Since MATLAB and Octave are mostly compatible, moving from one to the other is not hard and this reduces risk of being too dependent on one single company, especially if one switches over to Octave and then uses the no-cost redistribution rights to just expand operations to as many machines as are available. Octave runs exceptionally well on GNU/Linux, so no licence of Windows is required, either. In the coming days I’ll continue to post examples of what can be achieved with the more advanced functionality of Octave, including 3-D and video. It’s impressive and it by far exceeds my expectations given what I found in it around 5 years ago.
____
* There is a famous saying that goes like, “80% of the users of Microsoft Office only ever use 20% of its features.”

Some New Para-sites

IF traffic-jackers are a sign of Website maturity, then the mysterious birth of www.schestowitz.co.cc and www.schestowitz-com.co.cc should be a compliment. I had similar ‘issues’ over a couple of years ago. I wonder what other domains were born to capitalise on typos or a name.

Red Hat’s All Right!

NOW here’s a company that has so far shown that you can make a lot of money without annoying the community, without doing proprietary stuff (RHEL code is still available if you jump through hoops), and without strutting around in suits, commissioning ‘studies’, and making kitschy adverts.

If you think that Red Hat’s business is plateauing, you’re focusing on the wrong area. It’s not about middleware (e.g. JBoss). Global Desktop is coming next month and Red Hat already has an agreement for deployments (Australia at the least, probably with H-P and other OEMs/ VARs). If Red Hat can do on the desktop what it has done in the server room, then the future is bright for digital independence. Ubuntu (Canonical) also leaves me optimistic.

For the record, this is not “O/S war”. This is not a “my dick is bigger than yours” thing. It’s about freedom, which isn’t the case in an Apple vs. Microsoft debate (both are proprietary and lock-in oriented). Microsoft sees Linux as war and treats it in this way using propaganda (blatantly anti-Free software advertisements). It’s time to demand change.

Netscape and Digg Kings of the Hill

Wikipedia statistics

WEB statistics/tracking services share some very encouraging figures which suggest that Netscape and Digg lead the pack of social-driven news sites. As I am active on both sites, I am more than pleased to see this. Some time this weekend I will have submitted my 10,000th story to Netscape.

Knowing that Netscape attracts roughly 5 million unique users per month, I am certain that my contributions have an impact. They primarily promote digital freedom — something which I passionately believe in and therefore perpetually promote.

Second Interview with Google

Googleplex in London
Image of Googleplex in London (from ZDNet gallery)

LAST night I had my 2nd interview with google (a *nix systems administration position). What is noteowrthy is that I did not apply for a job. I was contacted by Google owing to my involvement and work on the Web. I am patiently waiting to hear their decision (should take several days), but I am pessimistic. Some questions were really hard and I needed hints. These questions were less analytical than I had expected.

Raves Du Jour

My opinion has just appeared in a CRN article. To quote the relevant bit:

“I have a gripe with what you claim and suggest. Essentially you propose robbing users from choice and diversity. Monocolutre is what GNU/Linux is here to address/tackle. Isn’t that what SLED is for? Corporate uniformity?

Why eliminate all others as contenders? And why spread FUD about compiling packages when there are such huge Ubuntu repositories?”

I referred to the original article in a previous blog post — that which motivated me to address the author. It seems as though, exposure-wise, the sun has begun to shine my way. I received the following E-mail last week (anonymised; anon replaces names/titles).

Hey there Roy,

I bet you’re getting a lot of email these days, thanks to Jason Calacanis’s post. So I’ll be quick.

You probably know anon, thanks to his blog (#36 in the world or thereabouts), his anon venture, and his books like anonand anon. Well, he’s got a new book coming out in August–called anon–which covers anon‘s best blog posts and rants and remarkable ideas of the last decade.

I’ve got a limited number of early books on hand. Any interest in a free copy? No strings attached.

I was shocked to find myself in such honourable position. I hope it’s all sustainable.

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Original styles created by Ian Main (all acknowledgements) • PHP scripts and styles later modified by Roy Schestowitz • Help yourself to a GPL'd copy
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