Patent Document ID: 8310546
Application ID: 12576315
Patent Status: 1

Claim One:
1. An image processing apparatus comprising: a processor configured to at least perform: an image data acquisition for acquiring, from an image acquisition apparatus provided with an image acquisition region comprising both a light-shielded region where a plurality of light-shielded solid-state image acquisition elements are arrayed as light-shielded pixels and a non-light-shielded region where a plurality of exposed solid-state image acquisition elements are arrayed two-dimensionally as effective pixels for acquiring an image of an object, data of the image based on output signals from the effective pixels which are provided by the solid-state image acquisition elements in the non-light-shielded region of the image acquisition apparatus; an output acquisition for acquiring output signals from the light-shielded pixels which are provided by the solid-state image acquisition elements in the light-shielded region; a noise estimation for estimating a degree of variations in levels of noise contained in the output signals from the effective pixels, based on the output signals acquired by the output acquisition; a threshold setting for setting the edge threshold based on both the degree of variations in noise which is estimated by the noise estimation and a maximum contrast which is set as a difference between a maximum and a minimum among levels of the output signals from the effective pixels based on the data acquired by the image acquisition; an edge extraction for extracting an edge in the image among the data of the image acquired by the image data acquisition, the edge being composed of pixels whose values has a difference equal to or large than the edge threshold between adjacent pixels in the effective pixels, the edge threshold being set by the threshold setting; and an object recognition for recognizing the object based on the edge extracted by the edge extraction, wherein the threshold setting is configured to set the edge threshold at a value falling into a range i) which is lower than the maximum contrast and ii) which allows the levels of the noise exceeding the edge threshold to occur at a probability lower than a preset value.