Gait Sequence Analysis using Frieze Patterns - Robotics Institute Carnegie Mellon University

Gait Sequence Analysis using Frieze Patterns

Yanxi Liu, Robert Collins, and Yanghai Tsin
Tech. Report, CMU-RI-TR-01-38, Robotics Institute, Carnegie Mellon University, December, 2001

Abstract

We analyze walking people using a gait sequence representation that bypasses the need for frame-to-frame tracking of body parts. The gait representation maps a video sequence of silhouettes into a pair of two-dimensional spatio-temporal patterns that are periodic along the time axis. Mathematically, such patterns are called ``frieze'' patterns and associated symmetry groups ``frieze groups''. With the help of a walking humanoid avatar, we explore variation in gait frieze patterns with respect to viewing angle, and find that the frieze groups of the gait patterns and their canonical tiles enable us to estimate viewing direction. In addition, analysis of periodic patterns allows us to determine the dynamic time warping and affine scaling that aligns two gait sequences from similar viewpoints. We show how gait alignment can be used to perform human identification and model-based body part segmentation.

BibTeX

@techreport{Liu-2001-8368,
author = {Yanxi Liu and Robert Collins and Yanghai Tsin},
title = {Gait Sequence Analysis using Frieze Patterns},
year = {2001},
month = {December},
institute = {Carnegie Mellon University},
address = {Pittsburgh, PA},
number = {CMU-RI-TR-01-38},
keywords = {gait analysis, frieze patterns, symmetry groups, AIC, model-based, moment-based, spatio-temporal analysis, gait alignment, frieze groups},
}