Face Age Estimation Using Contourlet Appearance Model

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Face age-estimation is challenging due to large variations in human faces, influenced by factors like gender, ethnicity, and environmental conditions, making it difficult for both humans and computing devices to accurately estimate age from facial images, especially in real-time applications without user cooperation.

Innovation Solution

The use of a contourlet appearance model (CAM) algorithm to extract feature vectors from facial images, combined with age classifiers and aging functions, allows for accurate age estimation by distinguishing between different age groups and accounting for unique aging mechanisms.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If exhaustive comparison methods are used to extract unique information from each image for accurate age-estimation, then measurement precision is improved, but computing time increases significantly

Engineering Contradiction:
Improveage-estimation accuracyVSAvoidcomputation time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent segments the complex task of age estimation into distinct phases: face detection, feature extraction using contourlet transform, and classification. This segmentation allows each component to be optimized independently, achieving accurate age estimation without requiring exhaustive comparison of all image features.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent extracts only the most relevant features from facial images using contourlet transform, rather than performing exhaustive analysis of all image data. This selective extraction of key features (such as facial contours, textures, and structural characteristics) maintains measurement precision while significantly reducing computation time.

Inventive Principle:
Principle #2Taking out (Extraction)

2Measurement precision

If multiple factors including uncontrollable environmental factors are considered in age-estimation, then measurement precision is improved, but device complexity increases

Engineering Contradiction:
Improveage-estimation accuracyVSAvoidsystem complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent introduces contourlet transform as an intermediary processing step that converts complex facial image data into a standardized feature representation. This intermediary transformation handles the complexity of multiple influencing factors (gender, ethnicity, environmental conditions) by converting them into comparable feature vectors, thereby improving measurement precision without increasing the apparent system complexity.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent changes the parameter representation from raw pixel data to contourlet transform coefficients, which better capture the essential characteristics of facial features across different age groups. This parameter transformation allows the system to account for various influencing factors (lighting, pose, ethnicity) while maintaining a consistent and manageable system structure.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentUS9311564B2Face age-estimation and methods, systems, and software therefor
Publication Date: 2016.04.12 CARNEGIE MELLON UNIV
  • US9311564B2 patent drawing
  • US9311564B2 patent drawing
  • US9311564B2 patent drawing

AI summary

Age-estimation of a face of an individual is represented in image data. In one embodiment, age-estimation techniques involves combining a Contourlet Appearance Model (CAM) for facial-age feature extraction and Support Vector Regression (SVR) for learning aging rules in order to improve the accuracy of age-estimation over the current techniques. In a particular example, characteristics of input facial images are converted to feature vectors by CAM, then these feature vectors are analyzed by an aging-mechanism-based classifier to estimate whether the images represent faces of younger or older people prior to age-estimation, the aging-mechanism-based classifier being generated in one embodiment by running Support Vector Machines (SVM) on training images. In an exemplary binary youth/adult classifier, faces classified as adults are passed to an adult age-estimation function and the others are passed to a youth age-estimation function.