Imaging System Exposure Control via Region of Interest Masking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional exposure control methods for imaging systems in vehicle environments are inefficient due to high processing power requirements, high costs, and inability to effectively handle extreme lighting variations, often resulting in ineffective exposure control.
Innovation Solution
A method and system that capture images, define a region of interest, analyze brightness within this region, calculate and adjust exposure time based on the analyzed brightness, using a controller and image processor to optimize exposure settings, thereby reducing processing power and improving adaptability to varying lighting conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If sophisticated histogram-based operations are used for exposure control, then exposure accuracy is improved, but processing time increases and the system becomes too slow for dynamic occupant sensing
Solution Approach 1:
The patent divides the image into multiple regions of interest (ROIs) and performs exposure analysis separately on each ROI rather than processing the entire image. This segmentation allows the system to focus computational resources on critical areas, reducing overall processing time while maintaining exposure accuracy for occupant detection.
Solution Approach 2:
The patent extracts only the necessary brightness information from specific regions of interest rather than performing comprehensive histogram analysis on the entire image. By taking out only the essential exposure data from key ROIs, the system achieves adequate exposure control with significantly reduced computational complexity and processing time.
2Speed
If special hardware designs are used to avert complex algorithms, then processing speed is improved, but cost and complexity of camera components increase
Solution Approach 1:
The patent replaces complex hardware-based exposure control mechanisms with a simplified software algorithm that analyzes brightness in regions of interest. This substitution achieves fast processing speeds through efficient computational methods rather than through complex hardware designs, thereby reducing camera component complexity and cost while maintaining processing speed.
3Measurement precision
If light-intensity detectors are integrated with the camera system, then exposure control accuracy is improved, but cost and device complexity increase
Solution Approach 1:
The patent enables the camera system to perform its own exposure control by utilizing the image data already captured by the sensor. The system analyzes brightness within regions of interest from the captured images and uses this information to adjust exposure parameters, eliminating the need for separate light-intensity detectors while maintaining exposure control accuracy.
4Device complexity
If global exposure control is used, then system simplicity is maintained, but effectiveness deteriorates under extreme intensity variations in the background
Solution Approach 1:
The patent applies different exposure analysis strategies to different regions of the image by defining specific regions of interest. Instead of uniform global exposure control, the system focuses on analyzing brightness in critical ROIs where occupant information is located, while ignoring or giving less weight to background regions with extreme intensity variations. This local quality approach maintains system simplicity while significantly improving exposure control effectiveness under varying lighting conditions.
Data Source
Figure 1~4
Figure 2~5
Figure 6~7
AI summary
A method (200) of exposure control for an imaging system (10). A predetermined number of images are captured (202) by one or more imagers (18), wherein the images are defined by an image resolution matrix. The images are masked (208) to establish a region of interest within the image resolution matrix and brightness of the images is analyzed (210) within the region of interest. An exposure time is calculated (228) for a subsequent image capturing step based on the brightness analysis, and an exposure time setting of the imager(s) is adjusted (230) during the subsequent image capturing step based on the calculated exposure time.