209 research outputs found
Objective Classes for Micro-Facial Expression Recognition
Micro-expressions are brief spontaneous facial expressions that appear on a
face when a person conceals an emotion, making them different to normal facial
expressions in subtlety and duration. Currently, emotion classes within the
CASME II dataset are based on Action Units and self-reports, creating conflicts
during machine learning training. We will show that classifying expressions
using Action Units, instead of predicted emotion, removes the potential bias of
human reporting. The proposed classes are tested using LBP-TOP, HOOF and HOG 3D
feature descriptors. The experiments are evaluated on two benchmark FACS coded
datasets: CASME II and SAMM. The best result achieves 86.35\% accuracy when
classifying the proposed 5 classes on CASME II using HOG 3D, outperforming the
result of the state-of-the-art 5-class emotional-based classification in CASME
II. Results indicate that classification based on Action Units provides an
objective method to improve micro-expression recognition.Comment: 11 pages, 4 figures and 5 tables. This paper will be submitted for
journal revie
Micro-facial movement detection using spatio-temporal features
Micro-facial expressions are fast, subtle movements of facial muscles that occur
when someone is attempting to conceal their true emotion. Detecting these movements
for a human is di�cult, as the movement could appear and disappear within
half of a second. Recently, research into detecting micro-facial movements using
computer vision and other techniques has emerged with the aim of outperforming
a human. The motivation behind a lot of this research is the potential applications
in security, healthcare and emotional-based training. The research has also
introduced some ethical concerns on whether it is okay to detect micro-movements
when people do not know they are showing them.
The main aim of this thesis is to investigate and develop novel ways of detecting
micro-facial movements using features based in the spatial and temporal domains.
The contributions towards this aim are: an extended feature descriptor to
describe micro-facial movement namely Local Binary Patterns on Three Orthogonal
Planes (LBP-TOP) combined with Gaussian Derivatives (GD); a dataset
of spontaneously induced micro-facial movements, namely Spontaneous Activity
of Micro-Movements (SAMM); an individualised baseline method for micromovement
detection that forms an Adaptive Baseline Threshold (ABT); Facial
Action Coding System (FACS)-based regions are proposed to focus on the local
movement of relevant facial areas.
The LBP-TOP with GD feature was developed to improve on an established
feature and use the GD to enhance the facial features. Using machine learning,
the method performs well achieving an accuracy of 92.6%. Next a new dataset,
SAMM, was introduced that improved on the limitations of previous sets, including
a wider demographic, increased resolution and comprehensively FACS coded.
An individualised baseline method was the introduced and tested using the new
dataset. Using feature di�erence instead of machine learning, the performance increased
with a recall of 0.8429 on the maximum thresholding and a further increase
of the recall to 0.9125 when using the ABT. To increase the relevance of what
is being processed on the face, FACS-based regions were created. By focusing
on local regions and individualised baselines, this method outperformed similar
state-of-the-art with an Area Under Curve (AUC) of 0.7513.
The research into detecting micro-movements is still in it's infancy, and much
more can be done to advance this �eld. While machine learning can �nd patterns
in normal facial expressions, it is the feature di�erence methods that perform the
best when detecting the subtle changes of the face. By using this and comparing
the movement against a person's baseline, the micro-movements can �nally be
accurately detected
3D-CNN for Facial Micro- and Macro-expression Spotting on Long Video Sequences using Temporal Oriented Reference Frame
Facial expression spotting is the preliminary step for micro- and
macro-expression analysis. The task of reliably spotting such expressions in
video sequences is currently unsolved. The current best systems depend upon
optical flow methods to extract regional motion features, before categorisation
of that motion into a specific class of facial movement. Optical flow is
susceptible to drift error, which introduces a serious problem for motions with
long-term dependencies, such as high frame-rate macro-expression. We propose a
purely deep learning solution which, rather than track frame differential
motion, compares via a convolutional model, each frame with two temporally
local reference frames. Reference frames are sampled according to calculated
micro- and macro-expression durations. We show that our solution achieves
state-of-the-art performance (F1-score of 0.126) in a dataset of high
frame-rate (200 fps) long video sequences (SAMM-LV) and is competitive in a low
frame-rate (30 fps) dataset (CAS(ME)2). In this paper, we document our deep
learning model and parameters, including how we use local contrast
normalisation, which we show is critical for optimal results. We surpass a
limitation in existing methods, and advance the state of deep learning in the
domain of facial expression spotting
Sheridan School of Architectural Technology Volume 3 [W2018+S2018]
This volume shows the work of the graduating students of the Architectural Technology programme. Once again, their hard work over three years of study shows both in the variety and in the quality of their work. The work presented here was prepared in a single course but it draws from all the courses in the programme. It reflects their capabilities in design, building science, legislation, regulations, graphical representation and technology. Each piece of work represents the individual blend of these that each student possesses. As they leave Sheridan they take with them a range of knowledge and skills that will start their careers. As their careers develop some will do exactly what they thought and more will move in completely new and unexpected directions. Please enjoy the work presented here and think of the future to come.https://source.sheridancollege.ca/fast_books/1005/thumbnail.jp
Combining physiological, environmental and locational sensors for citizen-oriented health applications
This work investigates the potential of combining the outputs of multiple low-cost sensor technologies for the direct measurement of spatio-temporal variations in phenomena that exist at the interface between our bodies and the environment. The example used herein is the measurement of personal exposure to traffic pollution, which may be considered as a function of the concentration of pollutants in the air and the frequency and volume of that air which enters our lungs. The sensor-based approach described in this paper removes the ‘traditional’ requirements either to model or interpolate pollution levels or to make assumptions about the physiology of an individual. Rather, a wholly empirical analysis into pollution exposure is possible, based upon high-resolution spatio-temporal data drawn from sensors for NO2, nasal airflow and location (GPS). Data are collected via a custom smartphone application and mapped to give an unprecedented insight into exposure to traffic pollution at the individual level. Whilst the quality of data from low-cost miniaturised sensors is not suitable for all applications, there certainly are many applications for which these data would be well suited, particularly those in the field of citizen science. This paper demonstrates both the potential and limitations of sensor-based approaches and discusses the wider relevance of these technologies for the advancement of citizen science
Automated Breast Ultrasound Lesions Detection Using Convolutional Neural Networks
Breast lesion detection using ultrasound imaging is considered an important step of Computer-Aided Diagnosis systems. Over the past decade, researchers have demonstrated the possibilities to automate the initial lesion detection. However, the lack of a common dataset impedes research when comparing the performance of such algorithms. This paper proposes the use of deep learning approaches for breast ultrasound lesion detection and investigates three different methods: a Patch-based LeNet, a U-Net, and a transfer learning approach with a pretrained FCN-AlexNet. Their performance is compared against four state-of-the-art lesion detection algorithms (i.e. Radial Gradient Index, Multifractal Filtering, Rule-based Region Ranking and Deformable Part Models). In addition, this paper compares and contrasts two conventional ultrasound image datasets acquired from two different ultrasound systems. Dataset A comprises 306 (60 malignant and 246 benign) images and Dataset B comprises 163 (53 malignant and 110 benign) images. To overcome the lack of public datasets in this domain, Dataset B will be made available for research purposes. The results demonstrate an overall improvement by the deep learning approaches when assessed on both datasets in terms of True Positive Fraction, False Positives per image, and F-measure.authorsversionPeer reviewe
3D-CNN for Facial Micro- and Macro-expression Spotting on Long Video Sequences using Temporal Oriented Reference Frame
Facial expression spotting is the preliminary step for micro- and
macro-expression analysis. The task of reliably spotting such expressions in
video sequences is currently unsolved. The current best systems depend upon
optical flow methods to extract regional motion features, before categorisation
of that motion into a specific class of facial movement. Optical flow is
susceptible to drift error, which introduces a serious problem for motions with
long-term dependencies, such as high frame-rate macro-expression. We propose a
purely deep learning solution which, rather than track frame differential
motion, compares via a convolutional model, each frame with two temporally
local reference frames. Reference frames are sampled according to calculated
micro- and macro-expression durations. We show that our solution achieves
state-of-the-art performance (F1-score of 0.126) in a dataset of high
frame-rate (200 fps) long video sequences (SAMM-LV) and is competitive in a low
frame-rate (30 fps) dataset (CAS(ME)2). In this paper, we document our deep
learning model and parameters, including how we use local contrast
normalisation, which we show is critical for optimal results. We surpass a
limitation in existing methods, and advance the state of deep learning in the
domain of facial expression spotting
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