Thermal Target Extraction Using Histogram Differentiation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for detecting and extracting warm or hot objects from thermal images are prone to false results due to inadequate segmentation techniques, especially when dealing with camera movements and scene changes, and are not power-efficient for handheld devices.

Innovation Solution

A method that estimates ambient temperature, differentiates histograms to set a reliable threshold, and filters dynamic threshold values using a weighted average to accurately segment targets from background clutter in thermal video frames.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If clustering or histogram methods are used for segmentation, then power consumption is reduced, but false target classification increases

Engineering Contradiction:
Improvepower consumptionVSAvoidfalse target classification
Core Design Contradiction:
Use of energy by moving objectVSReliability

Solution Approach 1:

The patent segments the thermal image into multiple clusters representing different temperature ranges (e.g., background, mid-temperature objects, hot targets). By dividing the temperature spectrum into distinct segments and analyzing the distribution of pixels in each segment, the method achieves both low power consumption (through simple histogram-based clustering) and high reliability (by examining multiple segments rather than relying on a single threshold).

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Instead of using a single threshold value that may cause false classifications, the patent applies multiple threshold levels corresponding to different temperature clusters. This partial action approach examines pixel distributions across several temperature bands, allowing the system to identify true targets by their characteristic presence in specific clusters while rejecting false alarms that don't match the expected cluster pattern.

Inventive Principle:
Principle #16Partial or excessive action

2Power

If clustering or histogram methods are used for segmentation, then computational power is reduced, but ability to account for scene changes deteriorates

Engineering Contradiction:
Improvecomputational powerVSAvoidscene change adaptation
Core Design Contradiction:
PowerVSAdaptability or versatility

Solution Approach 1:

The patent dynamically adapts the clustering parameters and threshold values based on the current scene characteristics. By continuously analyzing the pixel distribution across temperature clusters and adjusting the segmentation parameters accordingly, the system maintains adaptability to scene changes (such as camera movements or varying environmental conditions) while keeping computational requirements low through efficient histogram-based methods.

Inventive Principle:
Principle #15Dynamics

3Measurement precision

If Fourier analysis, pattern classification, or template matching are used, then segmentation accuracy is improved, but power consumption increases

Engineering Contradiction:
Improvesegmentation accuracyVSAvoidpower consumption
Core Design Contradiction:
Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent replaces complex, computationally expensive segmentation algorithms (Fourier analysis, pattern classification, template matching) with a simpler, lower-power alternative based on histogram analysis and cluster-based thresholding. While the simpler method requires less power, it achieves comparable segmentation accuracy by focusing on the statistical distribution of pixel temperatures rather than attempting complex pattern recognition, effectively using a 'cheaper' computational approach that consumes less energy.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

Data Source

PatentUS8611586B1Fast target extraction from thermal imagery
Publication Date: 2013.12.17 HARRIS CORP
  • US8611586B1 patent drawing
  • US8611586B1 patent drawing
  • US8611586B1 patent drawing

AI summary

A method for extracting a target from a series of images includes the steps of: (a) estimating an ambient temperature value of pixels in the series of images; (b) finding a band of pixel values having temperature values above the ambient temperature value, the band of pixel values forming a histogram; and (c) differentiating the histogram to estimate a threshold. Also included are steps (d) extracting the target having pixel values above the threshold; and (e) colorizing the target for display.