5,262 research outputs found
Robust arbitrary view gait recognition based on parametric 3D human body reconstruction and virtual posture synthesis
This paper proposes an arbitrary view gait recognition method where the gait recognition is performed in 3-dimensional (3D) to be robust to variation in speed, inclined plane and clothing, and in the presence of a carried item. 3D parametric gait models in a gait period are reconstructed by an optimized 3D human pose, shape and simulated clothes estimation method using multiview gait silhouettes. The gait estimation involves morphing a new subject with constant semantic constraints using silhouette cost function as observations. Using a clothes-independent 3D parametric gait model reconstruction method, gait models of different subjects with various postures in a cycle are obtained and used as galleries to construct 3D gait dictionary. Using a carrying-items posture synthesized model, virtual gait models with different carrying-items postures are synthesized to further construct an over-complete 3D gait dictionary. A self-occlusion optimized simultaneous sparse representation model is also introduced to achieve high robustness in limited gait frames. Experimental analyses on CASIA B dataset and CMU MoBo dataset show a significant performance gain in terms of accuracy and robustness
PsyMo: A Dataset for Estimating Self-Reported Psychological Traits from Gait
Psychological trait estimation from external factors such as movement and
appearance is a challenging and long-standing problem in psychology, and is
principally based on the psychological theory of embodiment. To date, attempts
to tackle this problem have utilized private small-scale datasets with
intrusive body-attached sensors. Potential applications of an automated system
for psychological trait estimation include estimation of occupational fatigue
and psychology, and marketing and advertisement. In this work, we propose PsyMo
(Psychological traits from Motion), a novel, multi-purpose and multi-modal
dataset for exploring psychological cues manifested in walking patterns. We
gathered walking sequences from 312 subjects in 7 different walking variations
and 6 camera angles. In conjunction with walking sequences, participants filled
in 6 psychological questionnaires, totalling 17 psychometric attributes related
to personality, self-esteem, fatigue, aggressiveness and mental health. We
propose two evaluation protocols for psychological trait estimation. Alongside
the estimation of self-reported psychological traits from gait, the dataset can
be used as a drop-in replacement to benchmark methods for gait recognition. We
anonymize all cues related to the identity of the subjects and publicly release
only silhouettes, 2D / 3D human skeletons and 3D SMPL human meshes
Covariate factor mitigation techniques for robust gait recognition
The human gait is a discriminative feature capable of recognising a person by their unique
walking manner. Currently gait recognition is based on videos captured in a controlled
environment. These videos contain challenges, termed covariate factors, which affect the
natural appearance and motion of gait, e.g. carrying a bag, clothing, shoe type and time.
However gait recognition has yet to achieve robustness to these covariate factors.
To achieve enhanced robustness capabilities, it is essential to address the existing gait
recognition limitations. Specifically, this thesis develops an understanding of how covariate
factors behave while a person is in motion and the impact covariate factors have on
the natural appearance and motion of gait. Enhanced robustness is achieved by producing
a combination of novel gait representations and novel covariate factor detection and
removal procedures.
Having addressed the limitations regarding covariate factors, this thesis achieves the goal
of robust gait recognition. Using a skeleton representation of the human figure, the Skeleton
Variance Image condenses a skeleton sequence into a single compact 2D gait representation
to express the natural gait motion. In addition, a covariate factor detection
and removal module is used to maximise the mitigation of covariate factor effects. By
establishing the average pixel distribution within training (covariate factor free) representations,
a comparison against test (covariate factor) representations achieves effective
covariate factor detection. The corresponding difference can effectively remove covariate
factors which occur at the boundary of, and hidden within, the human figure.The Engineering and Physical Sciences Research Council (EPSRC
GaitPT: Skeletons Are All You Need For Gait Recognition
The analysis of patterns of walking is an important area of research that has
numerous applications in security, healthcare, sports and human-computer
interaction. Lately, walking patterns have been regarded as a unique
fingerprinting method for automatic person identification at a distance. In
this work, we propose a novel gait recognition architecture called Gait Pyramid
Transformer (GaitPT) that leverages pose estimation skeletons to capture unique
walking patterns, without relying on appearance information. GaitPT adopts a
hierarchical transformer architecture that effectively extracts both spatial
and temporal features of movement in an anatomically consistent manner, guided
by the structure of the human skeleton. Our results show that GaitPT achieves
state-of-the-art performance compared to other skeleton-based gait recognition
works, in both controlled and in-the-wild scenarios. GaitPT obtains 82.6%
average accuracy on CASIA-B, surpassing other works by a margin of 6%.
Moreover, it obtains 52.16% Rank-1 accuracy on GREW, outperforming both
skeleton-based and appearance-based approaches
Learning discriminative features for human motion understanding
Human motion understanding has attracted considerable interest in recent research for its applications to video surveillance, content-based search and healthcare. With different capturing methods, human motion can be recorded in various forms (e.g. skeletal data, video, image, etc.). Compared to the 2D video and image, skeletal data recorded by motion capture device contains full 3D movement information. To begin with, we first look into a gait motion analysis problem based on 3D skeletal data. We propose an automatic framework for identifying musculoskeletal and neurological disorders among older people based on 3D skeletal motion data. In this framework, a feature selection strategy and two new gait features are proposed to choose an optimal feature set from the input features to optimise classification accuracy.
Due to self-occlusion caused by single shooting angle, 2D video and image are not able to record full 3D geometric information. Therefore, viewpoint variation dramatically affects the performance on lots of 2D based applications (e.g. arbitrary view action recognition and image-based 3D human shape reconstruction). Leveraging view-invariance from the 3D model is a popular idea to improve the performance on 2D computer vision problems. Therefore, in the second contribution, we adopt 3D models built with computer graphics technology to assist in solving the problem of arbitrary view action recognition. As a solution, a new transfer dictionary learning framework that utilises computer graphics technologies to synthesise realistic 2D and 3D training videos is proposed, which can project a real-world 2D video into a view-invariant sparse representation.
In the third contribution, 3D models are utilised to build an end-to-end 3D human shape reconstruction system, which can recover the 3D human shape from a single image without any prior parametric model. In contrast to most existing methods that calculate 3D joint locations, the method proposed in this thesis can produce a richer and more useful point cloud based representation. Synthesised high-quality 2D images and dense 3D point clouds are used to train a CNN-based encoder and 3D regression module.
It can be concluded that the methods introduced in this thesis try to explore human motion understanding from 3D to 2D. We investigate how to compensate for the lack of full geometric information in 2D based applications with view-invariance learnt from 3D models
Vision-based techniques for gait recognition
Global security concerns have raised a proliferation of video surveillance
devices. Intelligent surveillance systems seek to discover possible threats
automatically and raise alerts. Being able to identify the surveyed object can
help determine its threat level. The current generation of devices provide
digital video data to be analysed for time varying features to assist in the
identification process. Commonly, people queue up to access a facility and
approach a video camera in full frontal view. In this environment, a variety of
biometrics are available - for example, gait which includes temporal features
like stride period. Gait can be measured unobtrusively at a distance. The video
data will also include face features, which are short-range biometrics. In this
way, one can combine biometrics naturally using one set of data. In this paper
we survey current techniques of gait recognition and modelling with the
environment in which the research was conducted. We also discuss in detail the
issues arising from deriving gait data, such as perspective and occlusion
effects, together with the associated computer vision challenges of reliable
tracking of human movement. Then, after highlighting these issues and
challenges related to gait processing, we proceed to discuss the frameworks
combining gait with other biometrics. We then provide motivations for a novel
paradigm in biometrics-based human recognition, i.e. the use of the
fronto-normal view of gait as a far-range biometrics combined with biometrics
operating at a near distance
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