Sensory Flux from the Eye:


Ryan Janzen  and  Steve Mann
University of Toronto

Measuring Veillance

An Information-Bearing Extramissive Formulation of Sensing, to Measure Surveillance and Sousveillance

Ryan Janzen  and  Steve Mann
University of Toronto

Veillance Field

Veillance Flux

Information-Bearing formulation
of Extramission

How does light propagate?

Ibn al-Haytham
(11th century)
Regarded as a pioneer in the field of optics


Extramission concept: Rays of light emanating from the eyes.

We instead typically use intromission theory. now think of this as wrong. And yet... Yet, how do we measure the amount of veillance coming "out" of a camera? Not light coming out, but veillance coming out. What do we mean by "out"? Vernacular: camera "film shoot", "get a good shot" as if there's something coming out of the camera. How do we get a mathematical framework, an information-bearing precise quantification of veillance, the ability to see?
Veillance Field

Similar to holes vs. electrons in semiconductor physics.

Holes do not physically exist but are still widely used to account for current.

Need something beyond a darkon: A flow of darkons depends on the flow of photons. The ability to see should not vary with light incident on a pixel; that pixel’s purpose is to sense the presence or absence of light. By merely pointing a camera at an object, that action alone does not cause the object to emit light. Therefore, the darkon does not fully account for veillance.

"Spatial Jurisdiction" distinction between Surveillance and Sousveillance


Veillance Vector Field

Veillance intensity field

Veillance Flux

Sousveillance flux bit-rate:

Extramissive Vixel Analysis Algorithm


Degeneracy and Uniqueness of
reflected, scattered, blurred vixels

Effective Vixels v.s. Physical Vixels

Laser Scanning Vixel Independence Analysis

Veillometrics: Further applications

• Weather and Air Quality Sensing


• Composite dynamic range, composite impedance range sensing

• Audio

Conclusions: Veillometrics

• Vixels, Veillance Flux

• Information-bearing formulation of light propagation

• Physics and signal-processing to measure surveillance and sousveillance neutrally without political connotations

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