The artwork I kept thinking about after reading Levin’s essay was Cheese. The performers had to hold a smile while a computer measured it, and an alarm went off when their smiles dropped below a certain level. I can imagine laughing at that at first, then becoming very aware of my own face. It made me wonder when an artwork that responds to you starts to feel like it is judging you.
That example also made the difference between human and computer vision clearer to me. I might look at someone’s smile and wonder whether they are tired or joking. The computer needs a way to turn what its camera captures into something it can measure. Even finding a person in the image takes work. Frame differencing looks for changes between video frames, so someone standing still could disappear from its view. Background subtraction finds what differs from an empty scene, while brightness thresholding works when a person or object is clearly lighter or darker than its surroundings. I was surprised by how much the artist can help simply by changing the lighting or background.
I like Krueger’s idea that “the entire human body ought to have a role in our interactions with computers.” It opens up more playful possibilities than clicking a mouse. I would be curious to make something that reacts when a visitor turns toward it or moves away, without trying to decide what their expression means. Tracking can make a person feel involved in an artwork, but Cheese reminded me how easily that same attention can feel like surveillance. I think visitors should be able to tell when an artwork is watching them and choose whether to take part.
