Surveillance Camera Exposure Control via Local Area Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Surveillance camera systems face challenges in maintaining proper exposure for critical local areas within a shooting area, as existing automatic exposure control methods often result in overexposure or underexposure, especially when there are significant brightness variations or changes, and require complex image processing and limited versatility.
Innovation Solution
The system employs a combination of area surveillance cameras and local cameras, each with individual automatic exposure control, allowing for focused shooting of local areas with adjustable magnification and focal lengths, preventing exposure issues and enabling easy image combination for clear observation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If automatic exposure control is applied based on integrated brightness level of the overall shooting area, then the exposure control system requires less burden in terms of hardware and software and is stable in operation, but when great variation of brightness is caused in a part of the shooting area, its influence extends over the full screen causing overexposure or underexposure of the surveillance target
Solution Approach 1:
The patent divides the shooting area into multiple local areas, each with its own exposure control. Instead of using a single photometric value from the entire shooting area, the system calculates separate photometric values for each local area and controls exposure independently for each region, preventing brightness variations in one area from affecting the overall exposure accuracy
Solution Approach 2:
The patent implements different exposure control strategies for different local areas within the shooting area. Each local area can have its own exposure parameters optimized for its specific brightness characteristics, allowing the surveillance target in each region to be captured at proper exposure levels despite variations in the overall scene
2Manufacturing precision
If photometric value is calculated by dividing the shooting screen into pixel units or a plurality of areas to evaluate brightness distribution pattern, then exposure control can address brightness variations, but image processing becomes complicated and processing time is prolonged
Solution Approach 1:
The patent segments the shooting area into a predetermined number of local areas rather than analyzing at the pixel level. This coarse-grained segmentation reduces the computational burden while still capturing brightness distribution patterns across different regions, achieving a balance between processing simplicity and exposure accuracy
Solution Approach 2:
The patent pre-divides the shooting area into local areas and establishes exposure control for each region in advance. This preliminary segmentation and setup reduces the complexity of real-time image processing, as the system only needs to calculate photometric values for the predefined local areas rather than analyzing the entire image from scratch
3Manufacturing precision
If photometric program or exposure control program is changed in response to camera type or shooting magnification ratio, then exposure control can be optimized for specific purposes, but there is a drawback in the viewpoint of versatility
Solution Approach 1:
The patent creates a universal exposure control system that can handle different camera types and shooting magnification ratios through a standardized approach. By dividing the shooting area into local areas and applying exposure control based on photometric values from each region, the system maintains versatility across different camera configurations without requiring separate photometric programs for each scenario
Data Source
AI summary
A surveillance camera system includes a first camera 5 having an angle of view θ1, a second camera 6 which is a combination of two camera modules 6a, 6b each having an angle of view θ2, a third camera 7 which is a combination of three camera modules 7a, 7b, 7c each having an angle of view θ3, and a local camera 8 having an angle of view θs. The first to third cameras 5 to 7 act as area surveillance cameras to which the optimum shooting distance is set, respectively. The local camera 8 takes a shot of a local area, which is set in a shooting area of the third camera 7, at the narrowest angle of view θs. The respective cameras take a shot individually under automatic exposure control.