Gallery

Changing contrast, position, size and orientation of various shapes

Snapshot 1	Snapshot 2
Movie

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Distorting shapes by pinch-twist transformation

Snapshot 1	Snapshot 2
Movie

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Campbell-Robertson image: varying contrast and spatial frequency

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Moving gratings with different profile and wavelength,
separated by a gray ring

Snapshot 1	Snapshot 2
Movie

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Simultaneously moving, re-orienting and re-sizing 4096 objects

Movie

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Intensity profiles of modulated homogeneous illuminaton

"Chirp" stimulus, varying frequency

Varying amplitude, sinusoidal and square profile

Several amplitude modulation possibilities

Result of a Fourier synthesis of six frequencies, with random phases

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Random checkerboards
implemented through pixel by pixel white noise.

Intensity distribution was set by partitioning the random values spread in the [0..1] interval

Snapshot: Checkerboard in Cartesian coordinates, masked by a ring, binary intensity distribution	Snapshot: Checkerboard in polar coordinates, masked by a ring, binary intensity distribution
Checkerboard in Cartesian coordiantes, uniform grey intensity distribution
Color checkerboard implemented by uniform intensity distribution for each of the RGB color channels

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Convolution

Original image: light grey ring in a dark grey background

Inserts: the unchanged image corresponds to a convolution with a Kronecker delta in the real space, and with a constant function with a unitary amplitude in the Fourier space

Edge enhancement with different polignancy: convolution with zero-integral double-Gaussian profiles in the real or in the Fourier space, having different width (see inserts). These transform any spatially constant color into black. However, around edges, varying intensities emerge, even with values below zero and above one. Therefore, the convolution is followed by a histogram stretching which shifts zero intensities into the original grey, and fits all intensities within the unit range.

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Gabor stripes

Convolution by a modulated sinusoidal in the real space, or with a shifted Gaussian in the Fourier space (Kell az eredeti)

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Real-time spatio-temporal convolution or histogram equalization

Original movie and its global intensity histogram. Note that the [0..1] interval corresponds to the range of the possible intensities.
Movie after spatial convolution with a difference-of-Gaussians (DOG) bandpass filter providing edge enhancement,and its intensity histogram. The values marked with red are lagging out of the range of physically achievable intensities, i.e. the [0..1] interval.
Snapshot from the movie, and the intensity histogram renormed to the physically achievable interval, by a piecewise linear mapping (insert).
Snapshot from the movie, and the intensity histogram renormed to the physically achievable interval, by a sigmoidal mapping (insert).

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Temporal convolution

Movie	Movie after temporal convolution
Snapshot from a movie after temporal convolution, and the corresponding temporal kernel. Note the close black and the distant white color of the "tail" after the flying bird.

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Global picture distorsions

Movie with transformed image geometry.	Transformation of the image geometry, defined by an orthographic projection formula.

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Simple virtual realities

Walk within a labyrinth	Flight within a virtual enviroment 1
Flight within a virtual enviroment 2	Flight above a landscape

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Psychophysics

Kitaoka ("rotating wheel") illusion. GEARS enables the gradual change of the yellow color to blue. During this alteration, the illusion disappears.