Foot Position Estimation Using Vanishing-Point Geometry
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing techniques for estimating foot positions in images captured by cameras with wide-angle or fisheye lenses fail to accurately determine foot positions due to image distortion, leading to incorrect estimations.
Innovation Solution
A foot position estimating device that uses a processor to detect a human region in an image and estimates the intersection of a line from a reference point to the vanishing point with the human region's edge as the foot position, correcting for distortion based on the distance between the reference point and vanishing point.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If a wide-angle lens or fisheye lens is used to capture a large region, then the monitoring coverage is improved, but the image distortion increases causing incorrect foot position estimation
Solution Approach 1:
The patent changes the parameter of foot position estimation from simple lowest point detection to intersection point calculation based on vanishing point geometry. By using the geometric relationship between reference point, vanishing point, and human region edge, the system accurately determines foot position despite wide-angle distortion that alters apparent vertical positions in the image.
Solution Approach 2:
The patent introduces the vanishing point as an intermediary element to resolve the distortion problem. Instead of directly measuring foot position from distorted image coordinates, the system uses the vanishing point (where parallel lines converge in perspective) as a reference to establish accurate geometric relationships, effectively compensating for wide-angle lens distortion.
2Device complexity
If the lowest point in human region is used to estimate foot position, then the estimation process is simple, but the estimation accuracy fails under image distortion
Solution Approach 1:
The patent transforms the estimation approach from using image coordinate geometry (lowest point) to using perspective geometry (vanishing point relationships). This parameter change enables accurate foot position estimation by leveraging the mathematical property that lines converging at the vanishing point maintain accurate spatial relationships even under wide-angle distortion.
Solution Approach 2:
The patent performs preliminary detection of the vanishing point and reference point in the human region before calculating the foot position. By pre-establishing these geometric references from the distorted image, the system creates a corrected coordinate framework that enables accurate foot position measurement without requiring complex real-time distortion correction.
Data Source
AI summary
A foot position estimating device includes a processor configured to detect a human region representing a human in a predetermined region from an image generated by a camera configured to capture the predetermined region, and estimate a point of intersection of a line from a reference point in the human region to a vanishing point of the image with an edge of the human region as a foot position of the human, thereby correctly estimating a foot position of the human represented in the image.