68,343 research outputs found

    Seeing Through the Blur

    Get PDF
    Coordinated Science Laboratory was formerly known as Control Systems LaboratoryThis paper addresses the problem of image alignment using models such as affine and homography and by directly using pixel intensity values. Coarse-to-fine scheme has become a standard for direct intensity-based alignment. It is believed that such coarse-to-fine scale sampling (Gaussian blur) can improve region of convergence of the alignment optimization. Although, it has been proposed that such isotropic blur may not be optimal for some motion models, no rigorous derivation for such kernels has been known to date. In this work, we derive kernels for some of the common motion models such as affine and homography, which are able to smooth the alignment objective function. This is appealing because the smoothing process often removes poor local minima and thus reaches deeper solutions. Our derivation shows that these kernels coincide with Gaussian blur of the image only for displacement motion.National Science Foundation / NSF IIS 11-1601

    Video Manipulation Techniques for the Protection of Privacy in Remote Presence Systems

    Full text link
    Systems that give control of a mobile robot to a remote user raise privacy concerns about what the remote user can see and do through the robot. We aim to preserve some of that privacy by manipulating the video data that the remote user sees. Through two user studies, we explore the effectiveness of different video manipulation techniques at providing different types of privacy. We simultaneously examine task performance in the presence of privacy protection. In the first study, participants were asked to watch a video captured by a robot exploring an office environment and to complete a series of observational tasks under differing video manipulation conditions. Our results show that using manipulations of the video stream can lead to fewer privacy violations for different privacy types. Through a second user study, it was demonstrated that these privacy-protecting techniques were effective without diminishing the task performance of the remote user.Comment: 14 pages, 8 figure

    No Time to Move: Motion, Painting and Temporal Experience

    Get PDF
    This paper is concerned with the senses in which paintings do and do not depict various temporal phenomena, such as motion, stasis and duration. I begin by explaining the popular – though not uncontroversial – assumption that depiction, as a pictorial form of representation, is a matter of an experiential resemblance between the pictorial representation and that which it is a depiction of. Given this assumption, I illustrate a tension between two plausible claims: that paintings do not depict motion in the sense that video recordings do, and that paintings do not merely depict objects but may depict those objects as engaged in various activities, such as moving. To resolve the tension, I demonstrate that we need to recognise an ambiguity in talk of the appearance of motion, and distinguish between the depiction of motion and the depiction of an object as an object that is moving. Armed with this distinction, I argue that there is an important sense in which paintings depict neither motion, duration, nor – perhaps more controversially – stasis

    The simultaneity of complementary conditions:re-integrating and balancing analogue and digital matter(s) in basic architectural education

    Get PDF
    The actual, globally established, general digital procedures in basic architectural education,producing well-behaved, seemingly attractive up-to-date projects, spaces and first general-researchon all scale levels, apparently present a certain growing amount of deficiencies. These limitations surface only gradually, as the state of things on overall extents is generally deemed satisfactory. Some skills, such as “old-fashioned” analogue drawing are gradually eased-out ofundergraduate curricula and overall modus-operandi, due to their apparent slow inefficiencies in regard to various digital media’s rapid readiness, malleability and unproblematic, quotidian availabilities. While this state of things is understandable, it nevertheless presents a definite challenge. The challenge of questioning how the assessment of conditions and especially their representation,is conducted, prior to contextual architectural action(s) of any kind

    Edge-region grouping in figure-ground organization and depth perception.

    Get PDF
    Edge-region grouping (ERG) is proposed as a unifying and previously unrecognized class of relational information that influences figure-ground organization and perceived depth across an edge. ERG occurs when the edge between two regions is differentially grouped with one region based on classic principles of similarity grouping. The ERG hypothesis predicts that the grouped side will tend to be perceived as the closer, figural region. Six experiments are reported that test the predictions of the ERG hypothesis for 6 similarity-based factors: common fate, blur similarity, color similarity, orientation similarity, proximity, and flicker synchrony. All 6 factors produce the predicted effects, although to different degrees. In a 7th experiment, the strengths of these figural/depth effects were found to correlate highly with the strength of explicit grouping ratings of the same visual displays. The relations of ERG to prior results in the literature are discussed, and possible reasons for ERG-based figural/depth effects are considered. We argue that grouping processes mediate at least some of the effects we report here, although ecological explanations are also likely to be relevant in the majority of cases

    Perceptible ambiguity : learning center

    Get PDF
    This project investigates the possibility of using the concept of projection to blur a boundary, as well as the potential to create an ambiguous transition between various spaces. In this project, the differentiation between floors, inside and outside, solid and void, starts to fade away. Projection is a way to understand the world. Through “looking”, we “collapse” the original object, and reconstruct the image in our head. Learning is in the same way, we “break down” the phenomenon in order to comprehend the logic, and through experiments, we examine the theory repetitively. Learning is also about seeing the same thing from different perspectives in order to recognize the whole, and to create new forms through repetitive efforts. Projected lines constitute the project. Starts from an “original” point of view, the spaces grow through constant projection and back projection. The projected lines become solid and void elements. Spaces that defined by thick walls contain specific programs; while the rest of the spaces remain as large rooms open to various activities

    Realism in Film: Less is More

    Get PDF
    What is realism in film? Focusing on a test case of HFR high-definition movies, I discuss in this article various types of realism as well as their interrelations. Precision, recessiveness of the medium, transparency, and 'Collapse' are discussed and compared. At the end of the day, I defend the claim that 'less is more' in the sense that more image precision can actually have a negative impact on storytelling

    Isolating contour information from arbitrary images

    Get PDF
    Aspects of natural vision (physiological and perceptual) serve as a basis for attempting the development of a general processing scheme for contour extraction. Contour information is assumed to be central to visual recognition skills. While the scheme must be regarded as highly preliminary, initial results do compare favorably with the visual perception of structure. The scheme pays special attention to the construction of a smallest scale circular difference-of-Gaussian (DOG) convolution, calibration of multiscale edge detection thresholds with the visual perception of grayscale boundaries, and contour/texture discrimination methods derived from fundamental assumptions of connectivity and the characteristics of printed text. Contour information is required to fall between a minimum connectivity limit and maximum regional spatial density limit at each scale. Results support the idea that contour information, in images possessing good image quality, is (centered at about 10 cyc/deg and 30 cyc/deg). Further, lower spatial frequency channels appear to play a major role only in contour extraction from images with serious global image defects
    • …
    corecore