Camera Extrinsic Parameter Determination via Foot Strike Analysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for determining extrinsic camera parameters, such as pitch and roll angles, are inefficient and require complex model assumptions, especially when dealing with varying step lengths and orientations of objects in monitoring scenes.
Innovation Solution
The method utilizes foot strike points of walking objects to determine extrinsic camera parameters by forming step sections and using their lengths and ratios to calculate pitch and roll angles, allowing for recalculations based on camera settings.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If complex model assumptions are used to determine extrinsic camera parameters, then measurement precision may be improved, but device complexity and calculation overhead increase significantly
Solution Approach 1:
The patent extracts and utilizes only the essential geometric relationships from complex calibration models. By focusing specifically on foot strike points and step sections, the method isolates the minimum necessary information for determining pitch and roll angles, eliminating unnecessary model complexity while maintaining measurement precision.
Solution Approach 2:
The method uses the natural walking behavior of objects in the monitoring scene as self-provided calibration data. The foot strike points and step sections are automatically generated by the objects' own movement, eliminating the need for external calibration equipment or complex predetermined models. The system calibrates itself using readily available image data.
2Measurement precision
If traditional calibration methods are used, then comprehensive camera parameters can be determined, but the method requires complex model assumptions and is inefficient for varying step lengths and orientations
Solution Approach 1:
The patent segments the calibration process into distinct, manageable components: detecting foot strike points, forming step sections, and calculating pitch and roll angles from these sections. This segmentation allows each component to be processed independently and efficiently, improving overall productivity while maintaining precision.
Solution Approach 2:
The method dynamically adapts to varying step lengths and orientations by changing its processing parameters based on the detected foot strike points. Instead of relying on fixed model assumptions, the system adjusts its calculations to match the actual parameters observed in the monitoring scene, enabling efficient processing of diverse walking patterns.
3Productivity
If foot strike points are used to determine camera parameters, then model assumptions are minimized and efficiency is improved, but the method requires clear detection of foot contact points in image data
Solution Approach 1:
The patent enhances the detection of foot strike points by utilizing color or intensity changes in the image data. When a foot contacts the ground, it creates a distinct visual signature in the video sequence that can be automatically detected. This approach simplifies the detection process by relying on natural visual contrasts rather than complex geometric analysis.
Solution Approach 2:
The method replaces complex mechanical calibration systems with an optical detection approach. Instead of using physical calibration objects or mechanisms, the system uses image processing to detect foot strike points directly from video data, substituting mechanical complexity with optical sensing and computational analysis.
Data Source
AI summary
The invention relates to a method for determining extrinsic camera parameters of a camera 1, wherein foot strike points 11a, b of at least one object 8 walking on a monitoring base area 2 are determined based on image data of the camera 1, wherein the foot strike points 11a, b comprise at least three step sections 12a, b, wherein each step section 12a, b is defined by two foot strike points 11a, b, wherein the step sections 12a, b each have a section length on the monitoring base area 2, wherein a pitch angle 3 and/or a roll angle 4 of the camera 1 relative to the monitoring base area 2 is determined based on the location of the step sections 12a, b as well as a ratio of the section lengths on the monitoring base area 2 and/or based on the absolute section lengths on the monitoring base area 2.