Modelling of head movement in expression of disgust

Head movement modelling can be seen as a part of facial expression study because some expressions like disgust involves head movement. Head movement information can be acquired by video recording process. The recording process has to deal with image distortion correctable via plumb-line method. Unfortunately the linear fitting used in plumb-line requires piecewise function. The thesis aims to enhance the plumb-line-based image distortion correction using conic function coefficient evaluation replacing linear fitting. Experiments conducted shows that the proposed method handles various line orientations without having to rely on piecewise function. Besides distortion correction, an approach for expression movement tracking is needed. Optical flow-template matching is one of the techniques used for tracking. However, existing search algorithms did not discuss much on the looping technique of template matching. Moreover, tracking transient features during expression requires special process as the feature exists intermittently. The thesis aims to enhance the optical flow-template matching-based tracking method for tracking feature points during head movement by controlling the search loop and introducing anchoring to handle transient components. Experiment showed that the proposed method recorded a reduction in comparison of 40.1% over another similar method during worse case scenario. Besides reduction, the proposed method also lowered the lost point during searching when compared with existing method. Head movement modelling is not given proper attention in facial expression study hence affecting head model believability in computer graphics. The thesis aims to design head movement quantification method for head movement during disgust expression. The quantification method tracks movements of the head inclusive of the neck and named as ‘Dual Pivot Head Tracking’ (DPHT). To prove that it is perceptually better to use the proposed method, a perceptual study of expression with and without head movement was conducted. Results showed that subjects perceived disgust expression better if the proposed method is used ( -score of neck given head=14.9 vs. head given neck=3.59). To further support our proposal on the need to track head movement inclusive of the neck, experiments tracking subjects depicting disgust were conducted. A statistical two-tailed test to evaluate the existence of neck motion during head movement was done. Furthermore, visual comparison was made with a model without head movement approach. Results showed that neck motion was presence during head movement of disgust (z-score = 3.4 with p-value = 0.0006). Similarly the visual depictions showed that without the head movement inclusive of neck the rendering seemed to be incomplete. Having movement information, the thesis aims to design a temporal model of head movement during disgust expression. Neck motion, a part of head motion, plays a role during disgust expression. The thesis proposes spline-based function named Joint Cubic Bezier (JCB) to model neck motion during disgust. Experiments showed that using JCB, analysis and synthesis of neck motion during disgust expression is better than via cosine and exponential approach with angular separation score of JCB=0.986041, Exponential=0.897163 and Cosine=0.90773

Projecting image on non-planar surface with zero-th order geometric continuity using simple dual-linear function and manipulation of strict integer implementation in programming language

Usage of a projection system to display large screen images is still relevant in the midst of LED-based display increasing popularity.This is due to that the system itself is a mature technology, reliable and cheaper than the LED counterpart.While various methods had addressed the projection problems on curve surface, projecting image on jagged like surface (zero order geometric continuity) has yet to be studied in depth.This paper proposes a method for projecting image on non-planar surface with zero-order geometric continuity property using parametric modeling.The method manipulate linear function by combining two functions into one by taking advantage of computer programs strict implementation of integer variables.The method was applied to grid-based texturing algorithm in order to create the desired zero-continuity effect on the surface.The method was compared with texturing that implement existing curve algorithm to project image on the screen.Visual evaluation results showed that the proposed method fared better compared to existing curve-based projection algorithm

The potential use of augmented reality in gamification

The use of augmented reality (AR) and gamification in various fields is currently gaining popularity for its capability in engaging users.Gamification is a term that defines the use of game-based elements, such as game mechanics, aesthetics, dynamics, and game thinking in the non-game context environment.Meanwhile, AR is a technology that has an ability to overlap computer graphics onto the real environment.However, as a newly emerging concept, gamification seems to have some arguments related to its elements, concepts, and effectiveness in a similar intervention. Therefore, this paper discusses gamification. Although dozens of studies have implemented AR games, there is still an obvious lack in discussing and relating it to a gamified platform. Nevertheless, previous adaptation of games in AR seems that there are also potentials to utilise gamification and AR concepts and elements, as well as AR and AR games in brief.This paper also justifies several previous empirical studies in AR and gamification to look into its elements, research design, and the potentials of AR and gamification combinatio

Temporal modeling of head movement during facial expression via dual pivot tracking system: a case of disgust

Temporal modeling od facial expression is very important in various fields which include expression recognition, realism in computer animation and behavioral study in psychological field. While various researches are currently being done to capture the movement of facial features for its temporal property, not much is being said about the head movement during the facial expression process. The absence of head movement description can lead to incomplete expression description especially in the case of disgust where head movement can be a vital element for its depiction. Therefore, this paper proposes a method to track the movement of the head by using a dual pivot head tracking system (DPHT). In proving its usefulness, the tracking system will then be applied to track the movement of subjects depicting disgust. A simple statistical two-tailed analysis and visual rendering comparison will be made with a system that uses only a single pivot to illustrate the practicality of using DPHT. Results show that better depictions of expression can be implementad if the movement of the head is incorporated

3D based head movement tracking for incorporation in facial expression system

Head movement tracking is a necessary system in our attempt to establish the positioning of the head in an instance of the time. In computer graphics, head positioning sequence must be done in a proper manner so that the rendering will appear realistic. The head role becomes more important when a facial expression is being depicted. As a true facial expression must be accompanied with some motion of the head, rendering the facial expression without any proper description regarding head movement will make the head less realistic. This paper proposed a dual-pivot 3D-based head movement tracking system (DPHT) that enables modeler to capture the movement of the head. By having two pivots in the system, the movement of the neck can be modeled together with the yaw, roll and pitch of the head. This movement of the neck is an integral part of the facial expression depiction as can be attested by someone who 'pulls' his neck in manifestation of disgust. The results in this paper show that having a dual-pivot tracking system, head positioning can be better established hence producing more realistic head movement model

Dual-pivot pose determination of human head based on head movement

The pose determination is very important especially for system such as face tracking, face recognition, face analysis and even face modeling system. Pose determination is a pre-requisite step for establishing face orientation of which will be used in determining the shape and structure of the face. Existing rotation-based pose determination that describes head movement using a single pivot point cannot describe rotation that involves changes in pivot point. In addressing the issue, this paper suggests a pose determination technique via usage of two pivot points. The paper will propose a definition for dual-pivot pose determination, suggest approaches to calculate head movement along these pivots, show a brief application for the dual-pivot and give comment on advantages and disadvantages of dual- pivot points

Establishing the straightness of a line for radial distortion correction through conic fitting

Establishing straight lines in plumb-line based radial distortion correction is very important as the straight-line will determine the success of distortion correction operation. Various researches have been made to describe the line using linear fitting or polynomial fitting assuming that these fittings will augur well for distortion correction operation. However linear or polynomial fitting may not work in certain situation such as in vertical line. This research proposes a conic fitting method for establishing a straight-line. Fitting to a conic is more robust in a sense it can accommodate lines of different orientation

Design, development, utility and usability testing of the EMPOWER-SUSTAIN Self-Management Mobile App among primary care physicians and patients with metabolic syndrome

Objective This study aimed to design, develop, assess and refine the EMPOWER-SUSTAIN Self-Management Mobile App © among primary care physicians (PCP) and patients with metabolic syndrome (MetS) in primary care. Methodology Using the software-development-life-cycle (SDLC) iterative model, storyboard and wireframe were drafted; and a mock prototype was designed to illustrate the content and function graphically. Subsequently, a working prototype was developed. Qualitative studies using the ‘think-aloud’ and cognitive-task-analysis methods were conducted for the utility and usability testing. Topic guide was based on the 10-Nielsen's-Heuristic-Principles. Utility testing was conducted among PCP in which they ‘thought-aloud’ while performing tasks using the mobile app. Usability testing was conducted among MetS patients after they were given the app for 3 weeks. They ‘thought-aloud’ while performing tasks using the app. Interviews were audio- and video-recorded, and transcribed verbatim. Thematic content analysis was performed. Result Seven PCP and nine patients participated in the utility and usability testing, respectively. Six themes (efficiency of use, user control and freedom, appearance and aesthetic features, clinical content, error prevention, and help and documentation) emerged. PCP found the mobile app attractive and relevant sections were easy to find. They suggested adding ‘zoom/swipe’ functions and some parts needed bigger fonts. Patients commented that the app was user-friendly, has nice interface, and straightforward language. It helped them understand their health better. Based on these findings, the mobile app was refined. Conclusion This app was produced using a robust SDLC method to increase users’ satisfaction and sustainability of its use. It could potentially improve self-management behaviour among MetS patients in primary care