Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (p. [117]-124).

Thesis (Ph. D.)--University of Florida, 2001. / Title from title page of source document. Document formatted into pages; contains xiv, 150 p.; also contains graphics. Includes vita. Includes bibliographical references.

Thesis (Ph.D.)--Rochester Institute of Technology, 2009. / Typescript. Includes bibliographical references (p. 279-286).

Thesis (Ph. D.)--Carleton University, 2001. / Also available in electronic format on the Internet.

Thesis (MScIng)--University of Stellenbosch, 2005. / Appendix B on CD-ROM in pocket in book. Bibliography. Also available via the Internet.

Stop-motion animation is a traditional form of animation that has been practised for over 100 years. While the unique look and feel of stop-motion animation has been retained in modern productions, the production process has been modernised to take advantage of technological advancements. Modern stop-frame animation production integrates digital imaging technology and computational methods with traditional hand-crafted skills. This portfolio documents three projects undertaken at Aardman Animations, each investigated with the aim of improving efficiency in the stop-motion production process: - Rig removal is the removal of equipment, or ‘rigging’, used on set during stop-motion animation to hold characters or objects in unstable positions. All rigging captured in frames must be removed in post-production and currently manual methods are used which can be very time-consuming. The key task is to separate the character from the rig. In Chapter 2, I present a novel spatio-temporal segmentation algorithm for segmenting characters from stop-motion footage. The algorithm has been designed to work with stop-motion animated content, in contrast to other state of the art algorithms which struggled when tested on stop-motion footage. - Set shift is a problem which occurs when background items on set move subtly over the time taken to shoot a scene. For example, temperature and humidity changes can cause wood to warp during a weekend, changing the position of a background object the following week. These small ‘shifts’ are recorded in the footage and must be corrected in post-production. Chapter 3 describes the problem in detail, investigates potential solutions and explains why solving set shift automatically is a significant challenge. - Plasticine shading is required when a plasticine model has to be generated computationally. One motivation for producing footage computationally is that problems such as rig removal and set shift do not arise. In order to simulate plasticine accurately, the distinct reflectance model of this material must be known and reproduced. By collecting experimental data from plasticine samples and fitting parametric models, I have developed a bespoke surface shading model for plasticine (Chapter 4). This new model provides the best fit to the measured data when compared to existing state of the art surface shaders. It has been implemented into commercially used production systems, for use with existing rendering software. Advancing state of the art research is only one of the challenges when working in a production studio such as Aardman Animations. Additionally, findings must be integrated into the production pipeline. Chapter 5 discusses the challenges and constraints faced when conducting research in this environment. In order for stop-motion animation to remain competitive it is vital that production companies stay up-to-date with technological advancements in research areas that can contribute to their production processes. I conclude by discussing whether technological advancements can help Aardman Animations in improving the efficiency of their stop-motion production pipeline.

The study of rigid body rocking is applicable to a wide variety of structural and non-structural elements. The current applications range from bridge pier and shallow footing design to hospital and industrial equipment, even art preservation. Despite the increasing number of theoretical and simulation studies of rocking motion, few experimental studies exist. Of those that have been published, most are focused on a constrained version of the complete problem introducing modifications to the physical problem with the purpose of eliminating either sliding, uplift or the three dimensional response of the body. However, all of these phenomena may affect the response of an unrestrained rocking body. Furthermore, the majority of the experimental studies that have been published have used methods that are ill-suited to comprehensive three dimensional experimental analysis of the problem. The intent of this work is two-fold. First, to present a computer vision method that allows for the experimental measurement of the rigid body translation and rotation time histories in three dimensions. Experimental results obtained with this method will be presented to demonstrate that it obtains greater than 97% accuracy when compared against National Institute of Standards and Technology traceable displacement sensors. The experimental results highlight important phenomena predicted in some state-of-the-art models for 3D rocking behavior. Second, to present experimental evidence of the importance of characterizing the support medium as deformable instead of the commonly assumed rigid model. It will be shown in this work that this assumption of a rigid support may in some cases lead to non-conservative analysis that is unable to predict rocking motion and, in some cases, even failure.

We investigate some problems commonly found when dealing with stereo images. Working within the context of visual effects for films, we explore software solutions to issues arising with stereo images captured on-set. These images originate from a wide variety of hardware which may or may not provide additional data support for post-production needs. Generic software solutions are thus greatly to be preferred. This dissertation documents contributions in the following three areas. Each project was undertaken at Double Negative and investigated with the aim of improving the post-production pipeline for 3D films. Colour matching is the process whereby the colours of one view from a stereo pair are matched with those of the other view. This process is necessary due to the fact that slight differences in hardware and viewing angle can result in some surprisingly large colour discrepancies. Chapter 3 presents a novel approach to colour matching between stereo pairs of images, with a new tool for visual effects artists given in section 6.2.Vertical alignment of stereo images is key to providing a comfortable experience for the viewer, yet we are rarely presented with perfectly aligned footage from the outset. In chapter 4 we discuss the importance of correcting misalignments for both the final audience and the artists working on these images. We provide a tool for correcting misalignments in section 6.3.Disparity maps are used in many areas of post-production, and so in chapter 5 we investigate ways in which disparity map generation can be improved for the benefit of many existing tools at Double Negative. In addition, we povide an extensive exploration of the requirements of 3D films in order to make them presentable in the cinema. Through these projects, we have provided improvements to the stereo workflow and shown that academic research is a necessary component of developing tools for the visual effects pipeline. We have provided new algorithms to improve the 3D experience for moviegoers, as well as artists, and conclude by discussing the future work that will provide further gains in the field.

Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Title from first page of PDF file (viewed March 11, 2010). Available via ProQuest Digital Dissertations. Includes bibliographical references (p. ). Also issued in print.

Thesis (M. Sc.)--University of Canterbury, 2008. / Typescript (photocopy). "November 2008." Includes bibliographical references (p. 91-96). Also available via the World Wide Web.