The main difference between human vision and computer vision is the limitations of computer vision. The text mentions that “no computer vision algorithm is completely ‘general’.” This means that none of them can perform reliably given any possible video input. Each algorithm comes with specific assumptions about what the scene will look like, and if those assumptions aren’t met, the results can be poor, ambiguous, or completely broken. This is obviously very different from human vision which is significantly more adaptable. We are able to recognize almost anything in any environment.
However, one advantage of computer vision is its strength as a surveillance tool. Unlike human eyes, which can only see in normal light, computer vision systems can be paired with infrared or thermal cameras that work in complete darkness or detect body heat. This gives them a significant advantage as surveillance tools as they aren’t held back by the same biological limitations we are.
The techniques for helping the computer see better are mostly about manipulating the real world to suit the algorithm’s assumptions. Examples the text gives include using backlighting or retroreflective materials to create contrast, using infrared illumination in low-light conditions, choosing the right camera and lens for the situation, or even dressing subjects in specific colors. The idea is that good physical design and good code need to be developed together, not separately.
Computer vision’s limitations for surveillance mean that to incorporate them in interactive art, you need careful planning and knowledge on where this art will be, to appropriately plan for physical or environmental limitations. For instance, if you are creating a computer vision interactive art project for some exhibition, you will need to analyze the venue and its environmental conditions to ensure you use the right technique to properly analyze the subject(s) being surveilled.
Interestignly, the irony is that the very limitations of computer vision mean that in an art context, the surveilled person often has to cooperate with the conditions for the system to work at all. That’s quite different from CCTV, where you’re tracked without consent or awareness. So, interactive art using computer vision tends to occupy this strange middle ground where surveillance becomes participation, which raises its own questions about what it means to be watched by a system you’re also performing for. This becomes a crucial moral question when it comes to projects such as the suicide box mentioned in the text and David Rokeby’s Sorting Daemon, where people are participants in the art installations without their concent, especially during vulnerable moments such as with the case of the suicide box.