Dr Darren Wall

This thesis reviews and discusses the creation of photorealistic virtual human faces and tests audience perception of a series of specifically developed visual assets. This provides a detailed look at the human perception of such visuals. In addition, specific techniques required to produce and render the photorealistic visuals are investigated. Viewer testing informs the development of a series of computer-generated (CG) animated assets, through which the thesis introduces a range of metrics that shape the viewers’ experience. Moreover, technical and creative recommendations to the artist are provided in relation to developing similar assets.  The literature review considers how visuals of a realistic, although non-real, nature can in certain circumstances elicit a negative response in the viewer. This response can manifest as a feeling of repulsion, rather than empathy, towards the CG subject. Mori’s (1970) theory of the “uncanny valley effect” is considered as a hypothesis for predicting this response. This negative response is problematic for an artist attempting to develop photorealistic visuals. The uncanny valley effect is looked at in detail and established work in the field is built upon to consider animated visuals in addition to static images. Previous research does not fully address the perception of animated characters. This thesis shows how the addition of motion may affect viewer perception of the visuals. Moreover, the impact of image composition is taken into account.  Optimal asset generation processes are determined, employing relevant technologies, artistry and techniques. This was steered by experience and perception of the visuals. The methodology employed saw appropriately targeted individuals complete questionnaires and self-report documents to identify their objective feelings towards sample visual media. Test data was gathered, analysed and used to identify key visual triggers in the imagery. Accrued data informed the approach to develop refined CG assets, which were again tested.  Test One, Real or CG, gauges the accuracy of human perception in determining real (photographic) imagery from (CG) imagery. This provides a more comprehensive understanding of how and why viewers’ decisions and opinions were made. The test also aids the development of future research in identifying the key elements that inform the test subject's decisions.  Test Two, Is it in The Detail?, establishes whether a viewer requires an entire image or a fragment of an image to determine whether an image is real or CG. Here an informed decision is reached about whether the whole picture or merely close-ups of the key features delivers greater accuracy. Additional emphasises is given to the rationale for these differences.  Test Three, Photorealistic Character, takes the earlier tests a stage further, with the addition of movement. Participants judged a digital human asset in terms of realism in its static form and then again while in motion. The results of each exposure to the visuals were then compared. An additional comparison between full frame and close-up sections of animation was also conducted. Masahiro Mori’s (1970) uncanny valley theory regarding differences between perceptions of static and moving virtual humans is discussed here in relation to the recorded data.  The thesis shows that movement and composition of visuals have an impact on viewer perception of CG humans. The test data also confirms that the accuracy of the motion impacts upon the perceived human-likeness of the visuals.

Sonic and visual response to a watermill and the surrounding land commissioned by Leeds Museums and Galleries

This study explores 2.5D projection as a means of addressing the limitations in matte painted environments viewed from the perspective of a moving camera. In a shot from a fixed location, the viewer derives depth cues from the composition of the matte painting, but film directors are increasingly looking for more dynamic moving camera shots. Limitations in the artwork are exposed because forms contained within the painting become subject to new depth cues such as parallax and perspective, which change over time and cannot be derived from a 2D image under these conditions. A portfolio of three matte paintings has been developed using an action-based and reflective methodology. My weblog, submitted as an appendix to this thesis, provides access to the creative work and the instruments used to drive each project through multiple iterative stages of development. Each project in the portfolio is designed to expose the full range of 2.5D projection artifacts and describes how corrective strategies have been devised, tested and implemented. The final presentation of the portfolio is in the form of three short video sequences, each depicting a different matte painted environment seen through a moving camera. The study makes an original contribution to knowledge in three areas. Firstly, it lays the foundations for discourse within a subject area that is under-explored academically yet is as relevant to the visual effects industry as ever. Secondly, I present two new approaches to the production of matte painting artwork, both of which use arbitrary output values (AOV) render passes and 3D projection geometry to a greater extent than seen previously. The former provides a template for photo-bashing, and the latter serves the overpainting process. Thirdly, I present a diagnostic approach to camera projection deployed early in the project workflow to inform framing and drafting of the matte painting, thereby saving the artist time, effort and lost creative energy, improving efficiencies in the production in which the artist is employed. Matte painting, as an approach to the creation, extension or enhancement of digital environments remains as popular and extensively used as ever, despite the challenges presented by the demands of filmmakers and advances in the quality of outputs from 3D computer graphics applications. This study is helpful to 2D artists for developing their understanding of the tool chains, workflows and technical skills required to meet the demands of ever more imaginative and expansive shots. Moreover, I believe that environment artists, with some knowledge and experience of 2.5D workflows, will benefit from the depth of exploration and new insights provided in my work.

This research introduces a parametric framework to address the lack of educational resources for teaching realistic facial animation in digital characters, focusing on developing a Parametric Framework and Tool for Posing Photorealistic 3D Character Facial Expressions. The research applies the Facial Action Coding System (FACS), essential for understanding a wide range of realistic facial movements and enhancing digital characters' emotional depth and reliability. A novel innovation of the thesis is a tool that offers animators control over the range of movement of facial expressions. This tool's parametric functionality enables detailed, incremental adjustments, capturing human emotions' subtleties in digital form. The study demonstrates a systematic approach to developing a Parametric Framework and Tool for posing photorealistic 3D character facial expressions. It employs a Design Science Research Methodology, focusing on practical solution-oriented research. Key stages include problem identification, defining objectives, design and development of the tool, demonstration, evaluation, and communication. The process is iterative, integrating knowledge from facial expression theory, animation, computer graphics, and user interface design. The methodology emphasises user testing with animators and learners, incorporating feedback to refine the tool, ensuring practicality and utility for its intended users. The thesis emphasises successfully developing a Parametric Framework and Tool and highlights advancements in bridging the gap between theoretical knowledge and practical application in facial animation. The thesis concludes by underscoring the potential impact of this work on the animation industry, improving the emotional depth and realism of digital characters. Future directions for research and development are suggested, focusing on further enhancing the tool's capabilities and exploring new applications in various digital media contexts.