Patent ID: 8121404
Filing Date: 2012-02-21
Classification: G03B,G06K,G06T,H04N

Abstract:
1. An exposure control apparatus for controlling an exposure adjustment mechanism on a basis of an image signal captured by a solid-state image pickup device, the exposure control apparatus comprising: face detecting means for detecting a face of a person appearing in a captured image on the basis of the captured image signal; histogram data determining means for determining histogram data by setting a face detection region in the captured image according to detection information obtained by the face detecting means and detecting at least a brightness value of the face detection region from the captured image signal; target brightness setting means for setting a target brightness range for desired brightness of the face; exposure control amount determining means for, when the face detecting mean detects a face, determining an amount of control for the exposure adjustment mechanism on the basis of a first comparison result obtained by comparing a width of the target brightness range with a width of a range of a brightness region in a vicinity of a peak of histogram data corresponding to the face detection region and a second comparison result obtained by a second comparison, the second comparison being determined by the first comparison result and using a value in the target brightness range; overexposure/underexposure determining means for determining a degree of occurrence of overexposed areas and a degree of occurrence of underexposed areas in the captured image on a basis of a brightness value of a background region except for the face detection region in the captured image or a brightness value of an entire screen region; and control target shifting means for shifting the target brightness range according to a determination result obtained by the overexposure/underexposure determining means so as to shift the target brightness range toward a low-brightness side when the degree of occurrence of overexposed areas is high and to shift the target brightness range toward a high-brightness side when the degree of occurrence of underexposed areas is high, and supplying the shifted target brightness range to the exposure control amount determining means.