Camera Pose Estimation Using Length-First Line Segment Selection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for estimating the position and orientation of a camera in three-dimensional space by associating image data with CAD or shape information are computationally intensive, leading to impractically long calculation times as the number of feature lines and 3D-line-segments increases.
Innovation Solution
An estimation device that detects feature lines from an image and selects a subset of line segments based on a length-first selection order, generating combinations of these segments and feature lines for efficient association, thereby reducing the computational load and improving calculation speed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If all line segments and feature lines are associated with each other to estimate camera position and orientation, then the accuracy of estimation is improved, but the amount of calculation increases significantly
Solution Approach 1:
The patent extracts and selects only a subset of line segments that satisfy specific conditions (length, angle relationships, spatial distribution) from the complete set of available line segments. This selective extraction reduces the number of association pairs from all possible combinations to a manageable subset, thereby reducing computational complexity while maintaining estimation accuracy through careful selection of geometrically significant line segments.
Solution Approach 2:
The patent applies different selection criteria to different line segments based on their local geometric properties. Line segments are evaluated individually based on their length, orientation, and spatial relationships with other segments. This local quality assessment ensures that only line segments with favorable geometric characteristics contribute to the association, optimizing the balance between calculation efficiency and estimation accuracy.
2Measurement precision
If the number of association pairs is increased to improve estimation accuracy, then the precision of camera position and orientation is improved, but the calculation time becomes impractically long
Solution Approach 1:
The patent performs preliminary selection and filtering of line segments before the actual association process. By pre-evaluating line segments against geometric conditions (minimum length thresholds, angle constraints, spatial distribution requirements), the system prepares an optimized subset of candidate line segments in advance. This preliminary action significantly reduces the number of association pairs that need to be processed, thereby reducing calculation time while preserving the precision needed for accurate camera pose estimation.
3Productivity
If a subset of line segments is selected to reduce calculation amount, then the calculation speed is improved, but the accuracy of association may be degraded
Solution Approach 1:
The patent changes the parameters used for selecting line segments from a comprehensive set to a filtered set based on specific geometric criteria. By adjusting selection parameters (minimum length, angle thresholds, spatial distribution constraints), the system transforms the complete set of line segments into a reduced subset that maintains the essential geometric information needed for accurate camera pose estimation while enabling faster processing.
Solution Approach 2:
The patent ensures that the selected subset of line segments maintains high local quality by applying strict geometric criteria. Each selected line segment is evaluated for its contribution to the overall association accuracy based on its length, orientation, and spatial relationships. This quality-focused selection ensures that the reduced subset preserves the critical geometric features necessary for accurate camera position and orientation estimation.
Data Source
AI summary
An estimation device includes a processor coupled to a memory and configured to detect a plurality of feature lines from an image of the object photographed by an imaging device, generate a plurality of sets of a predetermined number of line segments among the plurality of line segments, select a set to be processed from among the plurality of sets based on a length-first selection order in which a line segment that is longer than other line segments is preferentially selected, generate the predetermined number of combinations in which the predetermined number of line segments included in the set to be processed and the predetermined number of feature lines among the plurality of feature lines are associated with each other on a one-to-one basis, and estimate a position and a orientation of the imaging device in a three-dimensional space using the predetermined number of combinations.