VisuApps
Optical illusions and blind spots — in humans and in machines.
Apps
A real MobileNet in the browser is fooled by an FGSM attack: an ε slider mixes gradient noise invisible to humans into the image until the label flips — alongside, the Adelson checkerboard shows the blind spots of humans. With webcam, drag & drop and procedural test images; a bridge to the robustness of camera-based quality inspection in the supply chain.
Perception & IllusionTry it
Four illusions that only work from a single viewpoint, as walk-around 3D stations: Ames room (giant and dwarf; the people swap corners), Penrose triangle as a real object with a gap, Beuchet chair and a rotating hollow mask with switchable lighting. A viewpoint slider moves from the peephole to the outside view. True shape, lines of sight and readouts show why the brain picks the most probable interpretation of an ambiguous retinal image.
Perception & IllusionTry it
A procedurally rendered still-life scene with warm light and a bluish shadow: an eyedropper proves that a "white" patch in shadow and a "gray" patch in light have exactly identical RGB values. A white-balance slider flips the same pixels between white-gold and blue-black (The Dress mechanics); a context toggle hides the lighting cues — and shows why industrial image processing needs controlled lighting and color calibration.
Perception & IllusionTry it
Two cube figures: same or mirror images? Response time grows with the rotation angle, and the chart measures your speed of mental rotation in degrees per second. Exhibit-ready.
Perception & IllusionTry it
A card deck with five classic optical illusions (Adelson checkerboard, Müller-Lyer, Ebbinghaus, Café Wall, simultaneous contrast) — each card with a precisely constructed SVG illusion and an animated proof button that makes the illusion collapse. A didactic entry into computer vision: perception is construction.
Perception & IllusionTry it
An animal runs through an arena, every spike of a neuron leaves a dot, and a hexagonal grid grows out of random paths. In a concept space of a bird's neck and leg length the same grid appears — the brain orders concepts like places.
Perception & IllusionTry itWant to use these apps in your courses? Let’s find out what works for you.
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