7 research outputs found
FIT Inner Stereopanorama
Tato bakalářská práce se zabývá kombinací stereoskopických a panoramatických fotografií. Popisuje možnosti tvorby panoramat se zaměřením na skládání ze sady snímků. Dále jsou zde rozebírány principy vnímání hloubky a možnosti projekce stereoskopických snímků. Součástí práce je aplikace pro prezentaci stereopanoramat interiérů Fakulty informačních technologií na internetu a její popis.This bachelor thesis is about combination of stereoscopic and panoramic photography. It describes creation of panoramas especially by stitching a set of images. Principles of depth perception and possibilities of stereoscopic images projection are discussed. This thesis includes software for presentation stereopanoramic pictures of Faculty of Information Technology interiors on the Internet and its description.
Using cross-talk simulation to predict the performance of anaglyph 3-D glasses
The anaglyph 3-D method is a widely used technique for presenting stereoscopic 3-D images. Its primary advantage is that it will work on any full-color display (LCDs, plasmas, and even prints) and only requires that the user view the anaglyph image using a pair of anaglyph 3-D glasses with usually one lens tinted red and the other lens tinted cyan (blue plus green). A common image-quality problem of anaglyph 3-D images is high levels of cross-talk — the incomplete isolation of the left and right image channels such that each eye sees a “ghost” of the opposite perspective view. An anaglyph cross-talk simulation model has been developed which allows the amount of anaglyph cross-talk to be estimated based on the spectral characteristics of the anaglyph glasses and the display. The model is validated using a visual cross-talk ranking test which indicates good agreement. The model is then used to consider two scenarios for the reduction of cross-talk in anaglyph systems and finds that a considerable reduction is likely to be achieved by using spectrally pure displays. The study also finds that the 3-D performance of commercial anaglyph glasses can be significantly better than handmade anaglyph glasses
Crosstalk in stereoscopic displays: A review
Crosstalk, also known as ghosting or leakage, is a primary factor in determining the image quality of stereoscopic three dimensional (3D) displays. In a stereoscopic display, a separate perspective view is presented to each of the observer’s two eyes in order to experience a 3D image with depth sensation. When crosstalk is present in a stereoscopic display, each eye will see a combination of the image intended for that eye, and some of the image intended for the other eye—making the image look doubled or ghosted. High levels of crosstalk can make stereoscopic images hard to fuse and lack fidelity, so it is important to achieve low levels of crosstalk in the development of high-quality stereoscopic displays. Descriptive and mathematical definitions of these terms are formalized and summarized. The mechanisms by which crosstalk occurs in different stereoscopic display technologies are also reviewed, including micropol 3D liquid crystal displays (LCDs), autostereoscopic (lenticular and parallax barrier), polarized projection, anaglyph, and time-sequential 3D on LCDs, plasma display panels and cathode ray tubes. Crosstalk reduction and crosstalk cancellation are also discussed along with methods of measuring and simulating crosstalk
Crosstalk in stereoscopic displays
Crosstalk is an important image quality attribute of stereoscopic 3D displays. The research presented in this thesis examines the presence, mechanisms, simulation, and reduction of crosstalk for a selection of stereoscopic display technologies. High levels of crosstalk degrade the perceived quality of stereoscopic displays hence it is important to minimise crosstalk. This thesis provides new insights which are critical to a detailed understanding of crosstalk and consequently to the development of effective crosstalk reduction techniques
Depth, shading, and stylization in stereoscopic cinematography
Due to the constantly increasing focus of the entertainment industry on stereoscopic imaging, techniques and tools that enable precise control over the depth impression and help to overcome limitations of the current stereoscopic hardware are gaining in importance. In this dissertation, we address selected problems encountered during stereoscopic content production, with a particular focus on stereoscopic cinema. First, we consider abrupt changes of depth, such as those induced by cuts in films. We derive a model predicting the time the visual system needs to adapt to such changes and propose how to employ this model for film cut optimization. Second, we tackle the issue of discrepancies between the two views of a stereoscopic image due to view-dependent shading of glossy materials. The suggested solution eliminates discomfort caused by non-matching specular highlights while preserving the perception of gloss. Last, we deal with the problem of filmgrainmanagement in stereoscopic productions and propose a new method for film grain application that reconciles visual comfort with the idea of medium-scene separation.Aufgrund der ständig steigenden Beachtung der stereoskopische Abbildung durch die Unterhaltungsindustrie, gewinnen Techniken und Werkzeuge an Bedeutung, die eine präzise Steuerung der Tiefenwahrnehmung ermöglichen und Einschränkungen der gegenwärtigen stereoskopischen Geräte überwinden. In dieser Dissertation adressieren wir ausgewählte Probleme, die während der Erzeugung von stereoskopischen Inhalten auftreten, mit besonderem Schwerpunkt auf der stereoskopischen Kinematographie. Zuerst betrachten wir abrupte Tiefenänderungen, wie sie durch Filmschnitte hervergerufen werden. Wir leiten ein Modell her, das die Zeit vorhersagt, die für das menschliche Sehsystem notwendig ist, um sich an solche Änderungen der Tiefe zu adaptieren, und schlagen vor wie dieses Modell für Schnittoptimierung angewendet werden kann. Danach gehen wir das Problem der Unstimmigkeiten zwischen den zwei Ansichten eines stereoskopischen Bildes, infolge der sichtabhängigen Schattierung von glänzenden Materialien, an. Die vorgeschlagene Lösung eliminiert das visuelle Unbehagen, welches von nicht zusammenpassenden Glanzlichtern verursacht wird, indessen bewahrt sie die Glanzwahrnehmung. Zuletzt behandeln wir das Problem des Filmkornsmanagements in stereoskopischen Produktionen und schlagen eine neue Methode für das Hinzufügen vom Filmkorn vor, die die visuelle Behaglichkeit mit der Idee der Medium-Szenen-Trennung in Einklang bringt
3D Multi-user interactive visualization with a shared large-scale display
When the multiple users interact with a virtual environment on a largescale
display there are several issues that need to be addressed to facilitate the
interaction. In the thesis, three main topics for collaborative visualization are
discussed; display setup, interactive visualization, and visual fatigue. The
problems that the author is trying to address in this thesis are how multiple
users can interact with a shared large-scale display depending on the display
setups and how they can interact with the shared visualization in a way that
doesn’t lead to visual fatigue.
The first user study (Chapter 3) explores the display setups for multi-user
interaction with a shared large-display. The author describes the design of the
three main display setups (a shared view, a split screen, and a split screen with
navigation information) and a demonstration using these setups. The user
study found that the split screen and the split screen with navigation
information can improve users’ confidence and reduce frustration level and
are more preferred than a shared view. However, a shared view can still
provide effective interaction and collaboration and the display setups cannot
have a large impact on usability and workload.
From the first study, the author employed a shared view for multi-user
interactive visualization with a shared large-scale display due to the
advantages of the shared view. To improve interactive visualization with a
shared view for multiple users, the author designed and conducted the second
user study (Chapter 4). A conventional interaction technique, the mean
tracking method, was not effective for more than three users. In order to
overcome the limitation of the current multi-user interactive visualization
techniques, two interactive visualization techniques (the Object Shift
Technique and Activity-based Weighted Mean Tracking method) were developed and were evaluated in the second user study. The Object Shift Technique translates the virtual objects in the opposite direction of movement
of the Point of View (PoV) and the Activity-based Weighted Mean Tracking
method assigns the higher weight to active users in comparison with
stationary users to determine the location of the PoV. The results of the user
study showed that these techniques can support collaboration, improve
interactivity, and provide similar visual discomfort compared to the
conventional method.
The third study (Chapter 5) describes how to reduce visual fatigue for 3D
stereoscopic visualization with a single point of view (PoV). When multiple
users interact with 3D stereoscopic VR using multi-user interactive
visualization techniques and they are close to the virtual objects, they can
perceive 3D visual fatigue from the large disparity. To reduce the 3D visual
fatigue, an Adaptive Interpupillary Distance (Adaptive IPD) adjustment
technique was developed. To evaluate the Adaptive IPD method, the author
compared to traditional 3D stereoscopic and the monoscopic visualization
techniques. Through the user experiments, the author was able to confirm that
the proposed method can reduce visual discomfort, yet maintain compelling
depth perception as the result provided the most preferable 3D stereoscopic
visualization experience.
For these studies, the author developed a software framework and designed
a set of experiments (Chapter 6). The framework architecture that contains
the three main ideas are described. A demonstration application for multidimensional
decision making was developed using the framework.
The primary contributions of this thesis include a literature review of multiuser
interaction with a shared large-scale display, deeper insights into three
display setups for multi-user interaction, development of the Object Shift
Techniques, the Activity-based Weighted Mean Tracking method, and the
Adaptive Interpupillary Distance Adjustment technique, the evaluation of the
three novel interaction techniques, development of a framework for
supporting a multi-user interaction with a shared large-scale display and its
application to multi-dimensional decision making VR system