Occluded Area Map for Object Tracking Re-identification

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing object tracking systems face challenges in handling occlusions, leading to lost object tracks and the need for computationally intensive re-identification processes, which are not always feasible, especially in systems using radar or lidar data.

Innovation Solution

A computer-implemented method for detecting occluded areas in video sequences analyzed by an object tracking system, which involves building a map of occluded areas by identifying areas where object tracks are lost and resumed, and using this map to improve tracking by adjusting coasting periods and prioritizing re-identification efforts.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If re-identification process is used to resume lost object tracks, then tracking reliability is improved, but computational resources and processing time are significantly increased

Engineering Contradiction:
Improvetracking reliabilityVSAvoidcomputational resources
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The system performs preliminary actions by maintaining coasting tracks that predict object positions during occlusion periods. Instead of immediately initiating computationally intensive re-identification when tracks are lost, the system uses preliminary coasting predictions to guide subsequent re-identification efforts, reducing the need for exhaustive feature matching by focusing computational resources on likely object locations and trajectories.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The tracking system segments the problem into distinct phases: active tracking, coasting (prediction during occlusion), and re-identification. By segmenting the computational workload across these phases and using simple coasting models during occlusion periods, the system reserves computational resources for re-identification only when necessary, rather than continuously performing expensive feature extraction and matching operations.

Inventive Principle:
Principle #1Segmentation

2Stability of the object's composition

If coasting is used to predict object position during occlusion, then tracking continuity is maintained, but errors accumulate over time

Engineering Contradiction:
Improvetracking continuityVSAvoidposition prediction accuracy
Core Design Contradiction:
Stability of the object's compositionVSMeasurement precision

Solution Approach 1:

The system dynamically adjusts the coasting period duration based on object characteristics, scene context, and occlusion conditions. Rather than using a fixed prediction horizon, the coasting mechanism adapts its temporal scope to balance continuity maintenance with error accumulation, switching to re-identification when prediction uncertainty reaches thresholds specific to each tracking scenario.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system incorporates feedback mechanisms where coasting predictions are continuously evaluated against new detections and scene context. When coasting errors are detected or when occlusion patterns suggest prolonged absence, the system triggers re-identification to correct accumulated errors, creating a feedback loop that maintains both continuity and accuracy.

Inventive Principle:
Principle #23Feedback

3Device complexity

If fixed coasting period is used for lost tracks, then system complexity is reduced, but adaptability to different occlusion scenarios is limited

Engineering Contradiction:
Improvesystem complexityVSAvoidadaptability to occlusion scenarios
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The system changes key parameters of the coasting mechanism dynamically, including prediction horizon, motion model complexity, and re-identification trigger thresholds, based on the specific occlusion scenario being encountered. This allows the same basic coasting framework to adapt to varying occlusion durations, object speeds, and scene complexities without requiring entirely different algorithms for each case.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP4488939B1A method and non-transitory computer-readable storage medium for detecting one or more occluded areas of a scene
Publication Date: 2025.04.02 AXIS
  • EP4488939B1 patent drawingFigure 1
  • EP4488939B1 patent drawingFigure 2~3
  • EP4488939B1 patent drawingFigure 4

AI summary

A method is presented for detecting one or more occluded areas of a scene analysed by an object tracking system. The method includes building (S506) a map of one or more occluded areas in a scene. Building the map comprises running (5510) a re-identification algorithm on a video sequence to try to resume a lost object track. If the object track is successfully resumed, the method includes determining (S512) an area of the scene where the first object track is lost and an area of the scene where the first object track is resumed. A connection between the first and the second area of the scene is added (S514) the map such that the map identifies that an object track being lost in the first area of the scene has been resumed in the second area of the scene.