Oblique Imagery Application for Undistorted Map Display
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Accurately associating pixels of oblique images with geographic coordinates is challenging due to image distortions caused by non-orthogonal camera angles and surface topography, making it difficult to display these images on maps without distortion.
Innovation Solution
An oblique imagery application determines a principal axis for the oblique image, calculates pixel vectors, and generates deviation coordinates to associate each pixel with geographic coordinates, creating an oblique tile that can be stored and displayed with a corresponding map tile, allowing for precise geographic location association and height estimation of features.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If oblique images are captured at non-orthogonal angles to provide perspective view, then the perspective view capability is improved, but the image distortion increases making accurate geographic location association difficult
Solution Approach 1:
The patent transforms the 2D oblique image coordinates into 3D spatial coordinates by introducing a vertical dimension. It calculates pixel vectors in 3D space that originate from the camera position and pass through each pixel, then determines where these vectors intersect the ground plane. This dimensional transformation allows the system to account for the oblique viewing angle and compute accurate geographic locations despite the perspective distortion.
Solution Approach 2:
The patent changes the coordinate system parameters from simple 2D image coordinates to 3D spatial coordinates incorporating camera position, orientation, and ground intersection points. By transforming the coordinate parameters and introducing deviation coordinates that account for the oblique angle, the system can accurately map pixels to geographic locations while preserving the perspective view capability.
2Ease of operation
If traditional mapping methods are used to display oblique images on maps, then the display simplicity is maintained, but significant image distortion occurs
Solution Approach 1:
The patent introduces an intermediary coordinate transformation process that acts as a mediator between the oblique image and the map display. It calculates intermediate values including pixel vectors, deviation coordinates, and ground intersection points that bridge the gap between the oblique perspective and the flat map coordinate system. This intermediary transformation enables accurate geographic association while maintaining ease of display integration.
3Measurement precision
If pixel vectors are calculated for each pixel to determine geographic coordinates, then the geographic location association accuracy is improved, but the computational complexity increases
Solution Approach 1:
The patent segments the image into discrete pixels and processes each pixel independently through the vector calculation process. By dividing the image into individual pixel units, the system can apply the complex 3D vector mathematics to each pixel separately, achieving high geographic location accuracy for every pixel while allowing parallel processing that manages the overall computational complexity.
Solution Approach 2:
The patent performs preliminary calculations of camera parameters, principal axis orientation, and pixel vector directions before the actual geographic coordinate assignment. By pre-computing these transformation parameters and storing them, the system reduces the real-time computational burden while maintaining high accuracy in the final geographic location association.
Data Source
AI summary
An oblique imagery application receives an oblique image captured by an oblique camera at a non-orthogonal angle with respect to a ground plane and map data including a map tile corresponding to geographic coordinates. A principal axis is determined that is orthogonal to an image plane defined by the oblique image and intersecting a center of the oblique image. For each pixel of the oblique image, a pixel vector is determined and a set of deviation coordinates based on a deviation of the pixel vector from the principal axis is determined for the pixel, with the pixel vector of a pixel passing through a focal point of the oblique camera and ending at the pixel. The map tile is associated to the pixels of the oblique image based on the camera parameters, the deviation coordinates of the pixels, the oblique camera parameters, and the geographic coordinates of the map tile.