Oversampled binary image sensor: Difference between revisions

Revision as of 20:58, 25 December 2015

Revision as of 03:49, 4 May 2016

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===The sensor===

[[File:binary sensor model.jpgsvg|thumb|right|300px480px|Fig.2 The model of the binary image sensor. The pixels (shown as "buckets") collect photons, the numbers of which are compared against a quantization threshold ''q''. In the figure, we illustrate the case when ''q'' = 2. The pixel outputs are binary: <math>b_m = 1</math> (i.e., white pixels) if there are at least two photons received by the pixel; otherwise, <math>b_m = 0</math> (i.e., gray pixels).]]

Fig.2 illustrates the binary sensor model. The <math>s_m</math> denote the exposure values accumulated by the sensor pixels. Depending on the local values of <math>s_m</math>, each pixel (depicted as "buckets" in the figure) collects a different number of photons hitting on its surface. <math>y_m</math> is the number of photons impinging on the surface of the <math>m</math>th pixel during an [[exposure (photography)|exposure]] period. The relation between <math>s_m</math> and the photon count <math>y_m</math> is stochastic. More specifically, <math>y_m</math> can be modeled as realizations of a Poisson random variable, whose intensity parameter is equal to <math>s_m</math>,