27 Apr 2010
Twinkle is my favourite software for making VoIP calls (under GNU/Linux). Here is how you configure it if you have an account with VoIPTalk.
Configuring the user
Enter your user details. Note that the SIP password is different from the password to log in on the VoIPTalk website. Log in on the VoIPTalk website and click on VoIPtalk ID to view VoIPtalk (SIP) password.
SIP server
Here you enter the details for the outbound proxy.
NAT
For firewall traversal you need to specify a STUN server.
Alternatively you can set up port forwarding on your router. Then you don’t need to specify a STUN server. In any case make sure that your firewall doesn’t block SIP traffic. You can call sip:905@voiptalk.org in order to test whether the configuration works.
I recommend using G.711 u-law as preferred audio codec.
Update:
In Kubuntu 10.04 you have to set all audio devices (input, output, and ringtone) to ALSA/Default.
There is a freeware VoIP client for Microsoft Windows called X-Lite.
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18 Apr 2010
If you are worried about the ash cloud of the current volcano eruption of Iceland, just think about more severe situations such as helicopter landings in the desert. Sand is essentially hard glass (and it melts in turbines of aircrafts leaving a nasty residue). Here’s a video of a helicopter landing in Kuwait.
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20 Jan 2010
I gave a talk titled Computer vision using Ruby and libJIT at the RubyConf 2009 in San Francisco. Confreaks has provided the video now.
You can download the talk from this webpage. The presentation slides are available here.
Let me know if you have any questions.
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12 Jan 2010
This video shows some capabilities of HornetsEye. The video was created with HornetsEye itself. The audio track is Depart by Tekno Eddy.
05 Dec 2009
Sceptics of the so called “scientific consensus” say that, while CO2 is a greenhouse gas, the effect of CO2 (see my prior article on the topic) on the global temperature is rather negligible and certainly not catastrophic. Furthermore only a small quota of the CO2 in Earth’s atmosphere is caused by human activity. However so far there has been significant political pressure on anyone who dares to say this in public. They are branded as “climate change deniers”.
A set of leaked e-mails from leading researchers around the world suggests cherry-picking of data and covering up the inconvenient truth. Climate Audit wrote about Climategate and published the complete text of the e-mail a couple of weeks ago already. The news has become viral since then. The e-mail is part of a larger (61 MByte) e-mail archive which has leaked by a whistleblower.
The Corbett Report interviewed Dr. Tim Ball about the Climategate scandal.
In the following report (which I found in a comment here) Rex Murphy notices that this could be an opportunity for the scientific community to get rid of global players and policy makers and restore the principles of proper scientific conduct.
In the video Climate Catastrophe Cancelled from 2007 a scene is shown where Tim Patterson speaks in front of a government panel in Canada warning them that “science and politics have become disconnected” and that we are going to end up “sending billions of dollars in the wrong direction”.
We must not allow global players such as Al Gore to take away our freedom and set the aggenda when it comes to issues concerning the future global economy. The only way to create an environmentally friendly and sustainable economy is the scientific way!
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