Dynamic Image Blurring for Privacy Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing privacy masking methods in surveillance systems are inflexible and require complex calculations for determining the appropriate degree of blurring in image data, often necessitating specific look-up tables and failing to adapt to varying use cases, such as blurring faces versus number plates.
Innovation Solution
A method that calculates the degree of blurring based on the difference between the maximum spatial resolution of image data and a threshold spatial resolution, applying the blurring only to areas beyond a defined threshold distance from the image capturing device, allowing for flexible adjustment according to the use case and reducing processing power.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a predetermined look-up-table is used to determine the amount of added blur based on F-number and distance, then the blurring degree can be determined, but the method becomes complex and requires specific look-up tables for every camera system reducing flexibility
Solution Approach 1:
The patent changes the parameters used for determining blurring degree from camera-specific parameters (F-number, distance with look-up tables) to image quality parameters (spatial resolution, signal-to-noise ratio). This allows the same method to be applied across different camera systems without requiring camera-specific calibration tables, thus reducing complexity while maintaining precision.
Solution Approach 2:
The patent creates a universal method for determining blurring degree that can be applied to any camera system regardless of its specific characteristics. By using spatial resolution and signal-to-noise ratio as the basis for blurring determination, the method becomes multi-functional and applicable to various surveillance scenarios and camera types without requiring separate look-up tables for each system.
2Reliability
If a protection target is detected within the focus range, then a relatively large blur amount is added for privacy protection, but this reduces the usability of the captured video for surveillance purposes
Solution Approach 1:
The patent implements dynamic blurring adjustment based on the calculated image quality metrics. Instead of applying a fixed large blur amount to all in-focus regions, the system dynamically determines the appropriate blurring degree by calculating spatial resolution and signal-to-noise ratio, then applying blurring only to the extent necessary to meet privacy requirements while preserving surveillance usability in other areas.
Solution Approach 2:
The patent applies different blurring degrees to different regions and scenarios within the image. By calculating spatial resolution and signal-to-noise ratio for specific areas, the system applies localized blurring adjustments rather than uniform blurring across the entire image, thus protecting privacy where needed while maintaining surveillance quality where appropriate.
3Reliability
If blurring is applied to ensure privacy protection, then specific details cannot be deciphered, but excessive blurring reduces the usefulness of the captured image for surveillance
Solution Approach 1:
The patent applies partial blurring action by calculating the minimum necessary blurring degree required to achieve privacy protection based on spatial resolution and signal-to-noise ratio measurements. Instead of applying excessive blurring to all privacy areas, the system applies only the partial amount of blurring needed to meet privacy requirements, thus preserving as much image detail as possible for surveillance purposes.
Data Source
AI summary
Methods and devices for protecting personal privacy in captured image data by controlling privacy masking of an image, where the degree of blurring to be applied to a privacy area of the image depends on a threshold distance from the image capturing device, and the spatial resolution of content of the scene at this distance in the image.