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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Video-Based Automated Emotional Monitoring In Mental Health Care supported by a Generic Patient Data Management System1</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Hayette Hadjar</string-name>
          <email>hayette.hadjar@fernuni-hagen.de</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Julian Lange</string-name>
          <email>julian.lange@fernuni-hagen.de</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Binh Vu</string-name>
          <email>binh.vu@fernuni-hagen.de</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Engel Felix</string-name>
          <email>fengel@ftk.de</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Mayer Gwendolyn</string-name>
          <email>gwendolyn.mayer@med.uni-heidelberg.de</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Paul Mc Kevitt</string-name>
          <email>p.mckevitt@ulster.ac.uk</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Matthias Hemmje</string-name>
          <email>mhemmje@ftk.de</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Heidelberg University, Department of Internal Medicine II, General Internal Medicine and Psychosomatics</institution>
          ,
          <addr-line>Heidelberg</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Research Institute for Telecommunication and Cooperation</institution>
          ,
          <addr-line>Dortmund</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Ulster University</institution>
          ,
          <addr-line>Derry/Londonderry</addr-line>
          ,
          <country country="UK">Northern Ireland</country>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>University of Hagen, Faculty of Mathematics and Computer Science</institution>
          ,
          <addr-line>Hagen</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>The detection of emotion and expression from video streaming plays a very important role in the mental health care of a patient. The data obtained from it can be used to support the diagnosis of emotional needs related to depression or other kinds of mental illnesses. These data can provide useful emotion monitoring information for health monitoring systems using automatic calculation of this Affective Computing (AC) information and storing them in patient data management systems. This research has been developed in the context of the SenseCare project, in order to support the treatment of patients with primary or comorbid mental disorders. There are two processes for tracking emotion in video, real-time, and offline facial expression video analysis. Real-time video analysis uses streamed webcam videos as data input. Offline video analysis uses pre-recorded video files as input. We focus in this paper on the realtime video analysis process, and we employ deep learning in web browsers for face detection and recognition using JavaScript.</p>
      </abstract>
      <kwd-group>
        <kwd>Video Content Analysis</kwd>
        <kwd>Affective Computing (AC)</kwd>
        <kwd>Emotion Recognition</kwd>
        <kwd>Facial Expression Analysis</kwd>
        <kwd>Emotions representation</kwd>
        <kwd>Emotional Monitoring</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction and Motivation</title>
      <p>
        Understanding and utilizing psychological knowledge in order to e.g. automatically
detect psychological events is one of the key research challenges in Affective
Computing (AC), especially in Research and Development (R&amp;D) of software related to
automatic emotion detection. Furthermore, ambient assisted living and
telemonitoring health care technologies can facilitate the collection of vital signal data
remotely (e.g., ECG, heart, and breath sounds) as well as the collection of
softwarebased automatic assessment and monitoring signals of mental or emotional status [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ].
      </p>
      <p>
        The SenseCare (Sensor Enabled Affective Computing for Enhancing Medical
Care) Platform [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] has been developed as a prototypical AC R&amp;D platform providing
software services applied to the care of patients with different support needs in the
field of mental health care. This technology provides various opportunities for
physicians, psychotherapists, clinicians, or other healthcare professionals. Such target user
groups can e.g, be enabled to intervene early in the case of a critical mental state that
could result in a crisis and thus a worsening of the patients’state of health. Hence,
primary care professionals can achieve an improved overview of the emotional
wellbeing of patients through the SenseCare [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] AC R&amp;D platform’s software services.
SenseCare integrates data streams from multiple sensors and fuses data from these
sensor signal streams to provide a global assessment that includes objective levels of
understanding emotional expressions, as well as the corresponding well-being, and
cognitive state of the patients. Several potential use cases for a system like SenseCare
underline the topicality, of which the recent crisis due to COVID-19 is only one:
Patients with mental disorders on isolation wards have to stay outside the support
system, as e.g. psychiatrists, psychologists, and other clinical staff fear infection [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ].
Remote, emotion-sensitive support could have supported these patients better and first
solutions in tele-medical intervention and corresponding pathways have been
developed in the meantime [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. Additionally, patients in an online group therapy setting
(e.g. due to rural provenience with low density of psychotherapists) can be supported
by emotion-sensitive videoconference tools. Recent changes in the accounting system
of e-health applications by health insurances will promote this development [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ].
Furthermore, patients with complex psychosomatic diseases often suffer from a comorbid
depression or anxiety, which leads to a vicious circle of deleterious effects. For
example, every fifth patient with heart failure suffers from depression, which may lead to a
lack of treatment adherence [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. Continuous monitoring of these patients by software
services of platforms like SenseCare may reduce high health related costs. Finally,
elderly patients in ambient assisted living are in need for a continuous monitoring of
their emotional state, as sudden changes in the mood can be a risk-marker for
dementia [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. Processing of voluminous data streams from video recordings, on the basis of
the recently introduced Information Visualization for Big Data (IVIS4BigData) model
[
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] elaborates data stream types addressed by our visualization approach.
      </p>
      <p>
        The so-called Knowledge Management Ecosystem Portal (KM-EP) is the
backbone system of the SenseCare platform [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] and is comprised of five subsystems
where each of them has several components of its own. The Information Retrieval
Subsystem (IRS) of the SenseCare KM-EP indexes AC content and enables users to
search for AC content using keywords, faceted search, and taxonomies. The Learning
Management Subsystem (LMS) of the SenseCare KM-EP provides tools for authors
and trainers to create AC-related e-learning courses using content in the SeneCare
KM-EP. SenseCare KM-EP users can later register in these SenseCare courses to
obtain new AC knowledge. The Content and Knowledge Management Subsystem
(CKMS) of the SenseCare KM-EP acts as a central repository for AC publications,
AC multimedia, AC software, AC R&amp;D dialogs, or AC-related medical records in the
SenseCare KM-EP. Producers of AC content can use components in this KM-EP
subsystem to import, create, manage, and classify their AC contents. Furthermore,
SenseCare KM-EP users can access these AC contents and rate their quality. The
User Management Subsystem (UMS) of the SenseCare KM-EP manages all users and
groups of the SenseCare KM-EP. Other systems can ask to authenticate SenseCare
KM-EP user’s identity using OpenID Connect [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] integrated into this SenseCare
KM-EP subsystem. The Storage Management Subsystem (SMS) of the SenseCare
KM-EP provides storage for files and documents. They can either be stored in a local
server or on the cloud for better access speed and availability.
      </p>
      <p>
        Solutions already exist for the administration of medical data and processes.
Incorporated within a specialist internship at the FernUniversität in Hagen were exemplary
projects: IndivoHealth [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] and Tolven [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ] considered as a solution for electronic
patient records and validated with regard to the requirements of SenseCare.
      </p>
      <p>
        On the practical side, our objective is to develop and implement further new
software modules as R&amp;D prototypes and corresponding AC software services that can
be integrated with the SenseCare KM-EP. Such R&amp;D results can then be re-used to
achieve some directions for future R&amp;D work in this domain. The main contributions
of this paper are:
 Implementation of a prototype module that collects patients’ facial expressions and
corresponding emotion data in real-time, during treatment sessions, or at home for
cases of patients with or at risk of a mental disorder. The software categorizes
emotional states according to the seven basic emotions described by Paul Ekman
(anger, contempt, disgust, enjoyment, fear, sadness, and surprise) [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ].
 The prototype employs deep learning in browsers by using JavaScript, and stores
results (Date - Time- Detected emotion) in a MongoDB.
      </p>
      <p>The remainder of this paper is organized as follows. Section 2 discusses the state of
the art of using sensors in healthcare, existing tools, and Convolutional Neural
Networks (CNNs). In section 3 we detail the conceptual design of modeling API,
information model and implementation of the solution, section 4 discusses our findings,
and finally we conclude in section 5.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Selected State of the Art and Related Work</title>
      <p>
        Research into wireless sensor networks and smart environments for remote
monitoring for healthcare applications [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ] employs wearable micro-machined sensors for
providing accurate biomechanical analysis under ambulatory conditions.
      </p>
      <p>
        In the continuous monitoring of human activities, wearable sensors can e.g. detect
abnormal and/or unforeseen situations by monitoring physiological parameters along
with other symptoms [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]. There are many software tools that employ methods of
machine learning to assist people in the areas of health.
      </p>
      <p>
        Eq-Radio [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ]: Researchers from MIT’s Computer Science and Artificial
Intelligence Laboratory (CSAIL) have developed EQ-Radio, a device that can detect a
person’s emotions using wireless signals. It transmits an RF signal and analyzes its
reflections off a person’s body to recognize his emotional state (e.g. happy, sad).The
key enabler underlying EQ-Radio is a new algorithm for extracting the individual
heartbeats from the wireless signal at an accuracy comparable to on-body ECG
monitors. EQ-Radio has three components: a radio for capturing RF reflections, a heartbeat
extraction algorithm, and a classification subsystem that maps the learned
physiological signals to emotional states [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ].
      </p>
      <p>
        Valossa AI [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ] is qualified to recognize sentiments and emotions from facial
expressions and speech, either from recorded video content or live feed. Mika
Rautiainen, founder and CEO of Valossa says that going through a video of a therapy
session takes a whole day from a human being. But AI tells her in a real-time analysis
what happens on the patient's face.
      </p>
      <p>
        FaceReady [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ]: from Noldus Information Technology is a facial expression
analysis software. It can automatically analyze the expressions happy, sad, angry,
surprised, scared, disgusted, and neutral. It can also calculate Action Units, valence,
arousal, gaze direction, head orientation, and personal characteristics such as gender
and age.
      </p>
      <p>
        SHORE® [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ] Software of Fraunhofer IIS enables the quick detection of faces and
objects as well as for the analysis of faces in image sequences, videos and single
frames. It can estimate gender, age and facial expressions in real time. The software
runs on standard Convolutional Neural Networks (CNNs) are a type of deep neural
network designed to process multiple data types, but it was initially designed to
analyze images [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ] CNNs are the most popular neural network model employed in
image classification [
        <xref ref-type="bibr" rid="ref22">22</xref>
        ], CNNs comprise several layers, such as the Convolutional
Layer, Non-Linearity Layer, Rectification Layer, Rectified Linear Units (ReLU), Pooling
Layer, Fully Connected Layer, and Dropout Layer.
      </p>
      <p>
        Existing solutions stream frames from a video stream over a network with OpenCV
[
        <xref ref-type="bibr" rid="ref23">23</xref>
        ] for the following advantages: (i) firstly, building a security application that
requires all frames to be sent to a central hub for additional processing and logging, and
(ii) secondly, the client machine may be highly resource-constrained (such as a
Raspberry Pi) and lack the necessary computational horsepower required to run
computationally expensive algorithms (such as CNNs).
3
      </p>
    </sec>
    <sec id="sec-3">
      <title>Conceptual Architecture of Health Information Subsystems</title>
      <p>The conceptual architecture of the Health Information System (HIS) within the
SenseCare KM-EP can be characterized by several subsystems which organize and
process information by specifying the type of data processed in each subsystem
independently of the others.</p>
      <p>Within the SenseCare KM-EP’s HIS, the Carna subsystem for data management
and information systems can run workflows for processing different types of AC data
(offline data and real-time data). Hence, it utilizes a workflow engine and enables
implementation of customized workflow action steps by Java code. The system
consists of different modules, the most important of which are Carna.dms (Data
Management System), Carna.process[emotion detection] (support processes, using the
example of Emotion Detection), and Carna.tenantmodules (general tenant-based
modules). Each Carna module within the SenseCare KM-EP’s HIS implements a
REST-API to access its functionality. Fig. 1 shows the most important of the
implemented REST interfaces.</p>
      <p>
        Fig. 1. SenseCare KM-EP HIS’s conceptual architecture of the Carna modules
supporting the integration of Health Care support processes [
        <xref ref-type="bibr" rid="ref24">24</xref>
        ].
      </p>
      <p>In the carna.dms module, among other data, process-related data and registered
processes are saved. When a workflow process is started for a patient, a new process
instance is initialized by the process module and an associated data record is created.
When a healthcare task (that is implemented by a process) is finished, a
documentation record is appended into the process-instance record table.</p>
      <p>To support the conceptual architecture and API modeling for the KM-EP HIS’s
Emotion Detection system, the activities of the SenseCare Emotional Monitoring Use
Case Scenario are:
1- The offline video analysis pipeline of the KM-EP HIS’s Emotion Detection
uses pre-recorded patient videos. These files are stored offline to be
pretrained with CNN models and classifiers in order to detect emotion from facial
expression.
2- The real-time video analysis of the KM-EP HIS’s Emotion Detection uses data
input from webcams for detection and recognition of facial expression in real
time, this process is the main focus of the remainder of this paper.</p>
    </sec>
    <sec id="sec-4">
      <title>Prototype Implementation of Emotion Detection</title>
      <p>A prototype solution for the SenseCare KM-EP Emotion Detection has been
developed with the Model-View-Controler (MVC) architecture paradigm. Hence, the
software prototypes’s source code is divided into three layers. On the model layer, data
storage, integrity, consistency, querying, and access support is allocated. The global
neural network models that are exported on this level from faceapi.js are
AgeGenderNet, FaceExpressionNet, FaceLandmark68Net, FaceLandmark68TinyNet,
FaceRecognitionNet, SsdMobilenetv1, TinyFaceDetector, Mtcnn, and TinyYolov2.
On the Controller level, the operations receive, interpret &amp; validate input, create &amp;
update are specified and implemented. On the View level, the query &amp; modify models
are specified and implemented. In our case the clinical user or the patient interacts
with the interface by means of a webcam on the view layer.</p>
      <p>The implementation of a corresponding REST API requires these elements:
1. Identify the objects that will be presented as a resource is the very first step in
designing a REST API-based application.
2. Create model URIs by designing the resource URIs – focus on the relationship
between resources and its sub-resources. There resources URIs are endpoints for
RESTful services.
3. Determine Representations: Mostly representations are defined in either XML or
JSON format. For example:
emotions: {angry: number, disgusted: number, fearful: number, happy:
number, neutral: number, sad: number, surprised: number}
Number in our case is the percentage of the security of the model that the
detectives have a particular emotion, each face element has expressions attribute.
Example:</p>
      <p>
        =&gt; surprised: 0.990011861078746733256
In the initial prototype implementation the following base technologies are employed:
 Tensorflow.js [
        <xref ref-type="bibr" rid="ref25">25</xref>
        ] is a library for machine learning in JavaScript, develop ML
models in JavaScript, and use ML directly in the browser or in Node.js.
 Face-api.js [
        <xref ref-type="bibr" rid="ref26">26</xref>
        ] is a JavaScript module, built on top of tensorflow.js core, and it
implements several CNNs for face detections and recognition, and it has been
optimized to work on web and mobile devices.
 Node.js [
        <xref ref-type="bibr" rid="ref27">27</xref>
        ] for synchronous or real-time communication in the web application, it
is employed to produce highly accurate face recognition and detection.
 MongoDB [
        <xref ref-type="bibr" rid="ref28">28</xref>
        ]: is an open source NoSQL database, it is a popular choice for
handling big data.
 Mongoose and NodeJSExpress [
        <xref ref-type="bibr" rid="ref29">29</xref>
        ] for transactions written in real-time and db
connectivity to MongoDB in order to store results of real-time video analysis of
facial expression.
The overall distribution and operational deployment of the system within client server
distribution architecture is shown in Figure 2 below.
      </p>
      <p>The system is divided into the frontend and the backend. The frontend in the
clients’ machine is combined of Face-api.js in TensorFlow.js, HTML/CSS/JavaScript,
and browser to display the front-end. The backend server is developed using NodeJS
Express, mongoose.Database, and MongoDB. The implementation allows both offline
video and stream video to be uploaded and processed. We can input an HTML
element like images or offline video using the id of the element, and input stream video
with function startVideo() to start webcam in the browser.
5</p>
    </sec>
    <sec id="sec-5">
      <title>Discussion of the findings</title>
      <p>The conducted experiment showed us that the developed module functionally meets
basic requirements, and it is important to implement additional functionality in order
to increase research study benefits. In the case of real-time video emotion recognition,
the SenseCare KM-EP HIS’s Emotion Detection API stores the best emotion detected
from the webcam in every 500 milliseconds, this choice of timing can be changed in
the API. The stored data has the following format:</p>
      <p>
        AllExpressiondetected: {date + time, label of best expression}
A part of the stored data in MongoDB can be seen in the table below.
"expression" : "neutral", "__v" : 0 }
{ "_id" : ObjectId("5f399f1e2232afa8b58f96ac"), "dateTime" : "2020-8-16 22:2:6",
"expression" : "neutral", "__v" : 0 }
A demonstration of face expression Recognition of images from “FACES A database
of facial expressions in younger, middle-aged, and older women and men” [
        <xref ref-type="bibr" rid="ref30">30</xref>
        ] is
shown in Figure 3.
      </p>
      <p>Image 1 Face Expression Recognition</p>
      <p>Image 2 Face Expression Recognition</p>
      <p>The prototype is under development and in our first observation during a test on
machines with different OSs (e.g. Windows, Ubuntu, MacOS), the values of the results
of real-time video emotion analysis, and the response time changes according to the
capacity and the hardware performance of the web server. Hence, a real-time
detection of emotions requires powerful hardware, e.g. Memory of the server must be
greater than 6 GB. And high quality images in the input stream are required to
identify a face (descriptor). We also observed that SSD Mobilenet V1 neural network gives
better accuracy then Tiny Face detector and MTCNN, and the accurate detection of
emotions based on facial expressions decreases when the light quality in the
experiment site decreases. Finally, the challenge is how we can recognize video facial
expressions with increased accuracy and in a quick inference time.
6</p>
    </sec>
    <sec id="sec-6">
      <title>Conclusion and Future Work</title>
      <p>In this paper, we describe the implementation of a video-based automated emotional
monitoring prototype consisting of two new subsystems of the SenseCare KM-EP.
The first subsystem that is a prototype implementation of the Carna Patient data
management and information system for the area managing healthcare service processes.
The second subsystem is the Emotion Detection subsystem that is implemented
prototypical to detect emotions based on analyzing facial expressions in videos.</p>
      <p>We discuss the use of CNNs in an initial prototype implementation to support face
detection and expression recognition supporting deriving corresponding emotion as
AC results. To establish a REST API we employ the face-api.js package, Node.js,
TensorFlow.js core, and MongoDB to store patient detected expressions with the date
and time in real-time.</p>
      <p>We also have presented an initial conceptual architecture as well as an initial
information model of our system and have specified the technical software architecture
of the API and discussed our first findings during the implementation of the API.
Future work includes:</p>
      <p>- Integration of the video-based automated emotional monitoring module in the
carna.dmg/KM-EP, and evaluation of the solution in a real HIS (Hospital Information
System, e.g. GNU Health).</p>
      <p>- Visualization and perception of all stored expressions or Graphical representation
of Emotions/Time, in order to make optimal decisions in healthcare.</p>
      <p>- Implementation of additional support processes in carna.dmg, and integration of
real sources such as video/audio data.</p>
    </sec>
  </body>
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