Underwater Image Distortion Correction via Depth-Specific Laser Calibration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for three-dimensional measurement underwater using stereo cameras face challenges with image distortion as water depth increases, due to pressure and mechanical changes, leading to incorrect calibration and measurement errors.
Innovation Solution
An image processor and method that utilize first and second laser light sources to capture images at different water depths, generating correction data to accurately correct distortion in captured images, ensuring precise three-dimensional measurement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If correction data acquired in advance is used to calibrate captured image, then calibration process is simplified, but measurement precision deteriorates due to mismatch between assumed and actual withstand pressure
Solution Approach 1:
The system performs preliminary calibration actions at multiple predetermined water depths before actual measurement. Correction data is pre-acquired at different pressure conditions (first water depth and second water depth) and stored for later use. This allows the calibration to be done in advance while maintaining accuracy by having depth-specific correction data ready when needed.
Solution Approach 2:
The system changes the parameter of water depth (pressure condition) during calibration and stores multiple sets of correction data corresponding to different depth parameters. When performing three-dimensional measurement, the system selects and applies the correction data that matches the actual water depth, thereby adapting to varying pressure conditions and maintaining measurement precision.
2Measurement precision
If stereo camera is used for three-dimensional measurement underwater, then measurement capability is enabled, but image distortion increases with water depth due to pressure and mechanical changes
Solution Approach 1:
The calibration process is segmented into multiple depth-specific calibration steps. Instead of using a single correction data set, the system divides the calibration into first calibration data (at first water depth) and second calibration data (at second water depth). This segmentation allows each depth range to have its own optimized correction parameters, improving reliability across varying depths.
Solution Approach 2:
The system dynamically adapts to changing water depth conditions by selecting appropriate correction data based on the current depth. The correction data is not fixed but changes according to the actual measurement conditions, allowing the system to maintain image quality stability despite pressure and mechanical changes at different depths.
3Device complexity
If calibration is performed at a single water depth, then calibration complexity is reduced, but adaptability to varying pressure conditions deteriorates
Solution Approach 1:
The system performs preliminary calibration actions at multiple predetermined water depths before actual measurement. Correction data is pre-acquired at different pressure conditions (first water depth and second water depth) and stored for later use. This allows the calibration to be done in advance while maintaining accuracy by having depth-specific correction data ready when needed.
Solution Approach 2:
The system changes the parameter of water depth (pressure condition) during calibration and stores multiple sets of correction data corresponding to different depth parameters. When performing three-dimensional measurement, the system selects and applies the correction data that matches the actual water depth, thereby adapting to varying pressure conditions and maintaining measurement precision.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution enables real-time correction of image distortion based on actual water depth, allowing for accurate three-dimensional measurement even under varying pressure conditions, thereby addressing the limitations of previous techniques.
Implementation Method 1
a first laser light source that emits first laser light underwater; a second laser light source that emits second laser light underwater
Data Source
AI summary
An image processor of the disclosure includes: an image sensor that captures an image of an underwater measurement target; a first laser light source that emits first laser light underwater; a second laser light source that emits second laser light underwater from a position that differs from the first laser light source; and a correction data generation unit that generates, on the basis of first information acquired by causing the image sensor to capture images of the first and second laser light beams at a first water depth and second information acquired by causing the image sensor to capture images of the first and second laser light beams at a second water depth which is a water depth at which the image sensor captures an image of the measurement target, correction data used to correct distortion in a captured image captured by the image sensor at the second water depth.