1. A moving object recognizing apparatus comprising: a data acquisition unit for acquiring image data obtained in time series by an imaging device; a recognition unit for recognizing a moving object by executing a plurality of image processing operations on two of the image data obtained at different times, said plurality of image processing operations including an operation of calculating correlativity of a same recognition target pattern, said recognition unit including a point feature extraction unit for extracting a point feature used as said recognition target pattern from the image data, an optical flow calculation unit for calculating optical flows, based upon said point feature present in said two image data obtained at different times, and a grouping unit for grouping, from among the optical flows, optical flows belonging to one moving object, under a predetermined condition; and a reliability calculation unit for calculating recognition reliability indicative of reliability of recognition of the moving object, based upon at least one of the results of the respective image processing operations by the recognition unit, said reliability calculation unit calculating the recognition reliability with using at least one of the group consisting of: a plurality of primary intermediate reliabilities which are calculated based on the respective results of a plurality of the image processing operations including the image processing operations executed by said point feature extraction unit, said optical flow calculation unit, and said grouping unit and which indicate reliabilities of the results of the respective image processing operations; a secondary intermediate reliability which is one selected from said primary intermediate reliabilities or a fusion of two or more of the primary intermediate reliabilities; an average reliability obtained by averaging the secondary intermediate reliabilities of those optical flows whose secondary intermediate reliabilities are included within a predetermined higher range; an object reliability calculated based upon correlativity between a size permissible for the moving object as one recognition target and a physical size delimited by an area where the optical flows grouped as belonging to the moving object are present, said object reliability indicating a degree of certainty whether the recognized moving object is truly the moving object to be recognized or not; and a position precision reliability calculated based upon the degree of dispersion of the positions of the optical flows grouped as belonging to the one recognized moving object and indicating the degree of certainty of the position of this recognized moving object.