Drew Clinkenbeard

    Which way is up? The natural inclanation is to think of everything above ones head as ‘up’. What of the people who are postiontioned 180° away from us on this spining ball of rock? It seems ‘up’ along with everything else is a matter of perspective.  What has made me think along these lines lately is the fact that I am working on a program to take the radial profile of an image. As a quick aside a radial profile is a method of sampling all of the pixels in an image radiating out in straight lines from the center of the image.

I was originally having some difficulty as I was thinking of it in that fashion.  How do you write a program to draw lines from the center of a square image and sample all the pixels, its near impossible.  Well it isn’t IF you change your perspective. I wish I was the one Who was responsible for the idea of the change but it wasn’t me.

The way it works is that you sample a pixel at a particular location (x,y), get the radial coordinate by taking the arctan of the coordinates of the pixel, compare that to your allowed bin values and you are done. Simple ONCE you have the perspective.

There has been a pretty pervasive theme to these entries lately. Almost all of them have had to do with programing.  Indeed they started with my stating I don’t like programing. This, as it turns out, was a lie.  The main reason I orginally became interested in programing is because it was the closest thing to magic to which I had access.  Now I have discovered the joy of physics and the further access to what would appear to be magic, it’s Arthur C. Clarke’s third law.

I have always been a fan of the Doppler effect. If that isn’t nerdy I don’t know what is. Seriously though I always liked the sound a car made when it went by, the way the wavelength got shorter as it approached and stretched out as it went away, of course I didn’t always know that was what was going on, but still. Now I am writing a papers on it and doing equations involving Doppler shifting. It is one of those things that is really simple when you think about it but it took a long time to ‘discover’ I would imagine it didn’t come up until we had the ability to move quick enough to notice it. I mean it is unlikely in the extreme that some one on foot or horse back is going to notice that “hey, Olaf’s voice seems to change as I charge at him.” or “Hmm these arrows sure seem to sound different as they fly past my head.” generally not situations conducive to scientific thought.

Considering scientific thought: ultrasonic imagery is really quite fascinating. The idea that we can use sound to ’see’ things is really very interesting, it makes me wonder if things like the heart beat sensor from the Rainbow Six games actually exist. Or could exist in the future. I don’t know if a specific heart beat sensor would be possible but I am sure it would be possible to create some sort of essentially portable sonar type of device that could identify soft tissue in a house at range. It would not be necessary to distinguish features as specific as a malfunctioning aorta but it would still be a good idea for police and such to have advanced knowledge of what they were heading into. With more information they would be better able to defend themselves and prepare for an encounter. (more…)