Image processing needs practitioners who can combine psychology, philosophy, and computer science.
By Andy Wilson
For my birthday, my son Doug bought me a jigsaw puzzle from Clementoni (Recanati, Italy; www.clementoni.com), a toy manufacturer founded by Mario Clementoni more than 40 years ago. My son thought that over a weekend we could spend a few hours trying to figure out how the puzzle pieces could be positioned to provide the picture rendered on the box.
Tearing off the wrapping paper, I was equally enamored with the puzzle he had chosen. There was a picturesque image of London Bridge taken from the South Bank of the Thames, with tulips blossoming in the foreground, boats with tourists cruising along the river, the Houses of Parliament, and a few strato-cumulous clouds hanging in the sort of wonderful blue sky that could have only be obtained with a Wratten color filter from Kodak (Rochester, NY, USA; www.kodak.com).
After feeling homesick for all of two minutes, my son and I started to piece together the problem. Being a rather intelligent chap, Doug soon figured out that it was probably easier to start with the edges of the puzzle, since they were the most well defined. But things didn’t really go to plan. Since all the edge pieces had been hoarded by my son, it was up to me to start on the colorful tulips. We really were not making the puzzle together but had unconsciously decided that a multitasking approach was the fastest way to accomplish the puzzle. And the effort, which was supposed to take one weekend, took a lot longer.
After all the outside edges, flowers, and the river were in place, it was time to start on the Houses of Parliament. Exhausted after two weeks of manual labor, I decided to let my son’s friends and anyone else who visited join in on the excitement. I thought of myself as a latter-day Tom Sawyer! Seeing the unfinished puzzle, one of his friends started putting together the government building. First, all the bits of the same color were hoarded, and then the outline of the magnificent monument materialized. Finally, the middle bits were filled in, and all that was left to complete was the blue sky.
When the dark patches of the sky with clouds were complete, a gaping hole was left in the puzzle where many blue pieces were supposed to be placed. And the puzzle remains that way as I write this. It’s not that we haven’t tried to accomplish the task. But the only time that any possible distinguishing color can be seen is in the morning when daylight, with its color temperature of 5500 K, shines through the window. Trying to ascertain any change in the colored pieces at night using a 2680 K, 40-W incandescent lamp is next to impossible.
But it’s not so much the color difference that is the problem. It’s the fact that a big hole remains with nothing in it.
I asked everyone I know what they thought. Thankfully, one of Doug’s friends recognized the problem. If there is nothing in the void, she pointed out, then you have to recognize the void itself. Thus, the only way to complete the task is to find each edge piece that makes up the big hole and work inward until the task is complete.
Such thoughts are not new. In his book Critique of Pure Reason (www.arts.cuhk.edu.hk/Philosophy/Kant/cpr/), Immanuel Kant stated that there can be no perception without prior knowledge and abilities. In assembling a puzzle, this prior knowledge can be attained by matching the pattern on the box with the pieces of the puzzle. But the ability to place the pieces together relies on a sophisticated human visual system that may be a parallel process that simultaneously compares edges, color, and light intensity with higher-level parameters such as depth cues and stored memory patterns.
Certainly, much could be learned by combining psychology, philosophy, and computer science. Unfortunately, in today’s segmented society, there is little synthesis between these subjects. In An Essay on Man (www.theotherpages.org/poems/pope-e2.html), Alexander Pope says that the proper study of mankind is man. This should be the anthem of every university. Until then, a large void will remain, just like the one in my house, now that my son has returned to college.