Saturday, February 12, 2005

I get sick of such a long post at the top of the list. This one is shorter, refreshing, cleansing.

Tuesday, February 08, 2005

Here are some facts about why things are the way they are:
1. Most of the energy in the frequency spectrum of a natural signal (noise, image, etc.) is at the low frequencies, and it drops off as a function of 1/f. This is because a big thing can have smaller things on it (like a field can have grass and rocks on it) but a small thing can't have bigger things on it. And also, as something gets smaller by x amount (i.e. * it by 1/x), its surface area gets another 1/x smaller (i.e. * it by 1/x squared). So the first 1/x is scaling wavelength, the inverse of frequency, and the second 1/x is like the potential energy at x (yes, at itself). Amazing!

So things have to be that way.

2. Most of the energy in natural scenes is at horizontal, and then vertical, orientations. This is because of gravity. Gravity makes things flat, causing horizons and other horizontal contours, and also vertical contours if you're up close and looking down on it. Living things, for one, contribute a lot to vertical energy. Otherwise (if they were dead) they'd be flat. So, on earth at least, you have tons of vertical symmetry, because they proper way for a thing to be is upright. Trees are vertical, people are vertical, cats are vertical, etc. So things also have to be that way.

3. Your brain already knows these things, even if you didn't know it knew. It's ready to process things in the environment according to regularities that it expects to find all over the place. This saves you time and energy, so you can expend it getting better at playing video games.

Now you've learned something! Tell everyone you know! But not engineers, they'll get picky on you. I hope no engineers are reading this.

Thursday, February 03, 2005

Any day now I'll think of something else to write about. Any day now I'll think of something. Any day now. Any day.

Any day now.