Auto-Focus Frame Arrangement Using Distortion Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional auto-focus methods in image capturing apparatuses face increased complexity and calculation loads due to the number of focus frames and their arrangement areas, especially when optical distortion is present, leading to deviations in focus frame positions between display and captured images.
Innovation Solution
The method involves correcting optical distortion in image data before focus frame arrangement, selecting reference coordinates, and determining focus frame intervals based on the corrected image data to accurately set in-focus control areas, thereby reducing deviations and maintaining real-time display characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the number of focus frames and arrangement area are increased to improve focus detection accuracy, then measurement precision is improved, but calculation amount increases remarkably and processing becomes complicated
Solution Approach 1:
The image data is divided into multiple focus frames arranged in a grid pattern, where each focus frame independently detects in-focus state. This segmentation allows the system to cover a wide area with multiple frames while keeping each frame's calculation simple and manageable
Solution Approach 2:
Distortion correction is performed on the image data before focus frame arrangement and detection. By correcting distortion in advance, the system establishes accurate correspondence between display image positions and captured image positions, enabling straightforward focus frame placement without complex real-time adjustments
2Measurement precision
If distortion correction is applied to improve focus frame position accuracy, then measurement precision is improved, but processing time increases
Solution Approach 1:
Distortion correction is executed as a preliminary step before focus frame arrangement. The corrected image data is then used to determine focus frame positions, allowing the system to maintain high position accuracy while separating the correction process from the real-time focus detection workflow
Solution Approach 2:
The patent uses correspondence relationships between display image coordinates and captured image coordinates to map focus frame positions. This coordinate mapping approach allows accurate position transfer without requiring repeated distortion correction calculations during focus detection
3Measurement precision
If multiple focus frames are arranged across wide area to improve coverage, then measurement precision is improved, but calculation amount increases remarkably
Solution Approach 1:
The wide area is divided into multiple independent focus frames, each performing simple contrast detection. This segmentation reduces the calculation burden per frame compared to analyzing the entire wide area as a single region, while maintaining overall detection accuracy through the combined results of multiple frames
Solution Approach 2:
Multiple focus frames are arranged in a grid pattern covering the wide area, and their detection results are combined to determine overall in-focus state. This merging approach allows the system to achieve wide coverage and high accuracy by aggregating simple individual frame detections rather than performing complex analysis on the entire area
Data Source
AI summary
An apparatus includes a reference coordinate selection unit configured to select reference coordinates of two points from a focus frame area set by a setting unit, and determines arrangement intervals of focus frames based on coordinates on image data before correction corresponding to the coordinates selected by the reference coordinate selection unit and a number of focus frames.