Keypoint Time-Series Reidentification Without Facial Data

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Person re-identification in video analytics systems remains challenging, particularly in multi-camera surveillance, and facial recognition, while effective, raises significant privacy concerns.

Innovation Solution

Represent objects in video data as sets of key points forming timeseries, which serve as unique 'fingerprints' for identification across different video feeds, eliminating the need for facial recognition.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If facial recognition is used for person re-identification, then identification accuracy is improved, but privacy concerns increase

Engineering Contradiction:
Improveidentification accuracyVSAvoidprivacy concerns
Core Design Contradiction:
Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The patent extracts only the necessary geometric and motion features from video data without capturing or storing facial images. By taking out only the essential identification information (keypoint coordinates and motion patterns) while leaving out the sensitive facial data, the system achieves accurate person re-identification while preserving privacy.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent introduces an intermediary representation layer between video input and identification output. Instead of directly using facial images for identification, the system uses keypoints and timeseries as an intermediary that captures identification-relevant information while discarding privacy-sensitive visual details.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Object-affected harmful factors

If traditional person re-identification methods are used, then privacy is preserved, but re-identification accuracy decreases

Engineering Contradiction:
Improveprivacy protectionVSAvoidre-identification accuracy
Core Design Contradiction:
Object-affected harmful factorsVSMeasurement precision

Solution Approach 1:

The patent transitions from spatial-only features to spatio-temporal features by introducing the time dimension through timeseries analysis. This dimensional expansion enables accurate re-identification using privacy-preserving methods by capturing motion patterns and temporal dynamics that are invisible to traditional spatial-only approaches.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent changes the feature representation parameters from visual appearance (facial images) to geometric and temporal parameters (keypoint coordinates and motion patterns). This parameter transformation maintains identification accuracy while fundamentally altering the data type to be privacy-preserving.

Inventive Principle:
Principle #35Parameter changes

3Adaptability or versatility

If facial recognition systems are deployed, then person identification capability is improved, but system complexity increases

Engineering Contradiction:
Improveperson identification capabilityVSAvoidsystem complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent segments the person representation into discrete keypoints rather than processing entire facial images. This segmentation simplifies the data structure and processing requirements while maintaining identification capability, reducing system complexity compared to full facial recognition systems.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentUS12536800B2Privacy preserving person reidentification
Publication Date: 2026.01.27 CISCO TECHNOLOGY INC
  • US12536800B2 patent drawing
  • US12536800B2 patent drawing
  • US12536800B2 patent drawing

AI summary

In one embodiment, a device represents each of a plurality of objects depicted in video data captured by a plurality of cameras over time as a set of key points associated with that object. The device forms, for each of the plurality of objects, a set of timeseries of the set of key points associated with that object. The device performs reidentification of a particular one of the plurality of objects across video data captured by two or more of the plurality of cameras by matching sets of timeseries of key points associated with that object derived from video data captured by two or more of the plurality of cameras. The device provides an indication of the reidentification for display to a user.