Spatial Structure From Temporal Structure:
Random Luminance Modulation
In this animation, the all pixels in the "figure" region follow the same point process while the point processes of pixels in the "surround" are uncorrelated.
In this animation, the all pixels in the "figure" region follow the same point process while those in the surround all follow a different, independent point process.
The time series for any given pixel in these kinds of dynamic displays defines that pixel's magnitude of luminance change, direction of luminance change and time of luminance change. Each pixel has its own individual "time-line" and these time-lines are unrelated to one another in direction and magnitude of change; only the correlation of their point processes (i.e., points in time at which change occurs) provides information about their "common fate." Two sets of these kinds of time-series are shown below. Note that members of the set in the top panel (which might consist of pixels within a "virtual area") change in luminance randomly over time, with each changing in magnitude and direction independently of all others. Note, however, that all pixels change at the same time (as indicated by the tiny "spikes" at the bottom of the panel. The same is true of the members of the set shown in the bottom panel. Importantly, note that the two sets of pixels follow different time series.
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