Adaptive camera regulation for investigation of real scenes
An adaptive strategy for regulating the intrinsic parameters of a charge coupled device (CCD) visual camera is presented. The parameter regulation procedure is based on the computation of the "quality" of an acquired signal by means of a set of functions which estimate the goodness of the datum. Each function performs a quantitative evaluation by computing several features derived from the high-frequency content of an image or from the histogram analysis. The regulation strategy uses such values to compute the actual values of the camera parameters, i.e., focusing distance, aperture diameter, electronic gain, and black level. Moreover, the same strategy can be applied both to the whole image and to smaller subareas, therefore providing a focus-of-attention mechanism. This is useful for automatic investigation and control of environments subject to dynamically changing conditions (e.g., illumination and structure of a scene), whenever it is not possible to interact directly with such environments.