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When rendering effects such as motion blur and defocus blur, shading can become very expensive if done in a naive way, i.e. shading each visibility sample. To improve performance, previous work often decouple shading from visibility sampling using shader caching algorithms. We present a novel technique for reusing shading in a stochastic rasterizer. Shading is computed hierarchically and sparsely
Given a stochastic shadow map rendered with motion blur, our goal is to render an image from the eye with motion-blurred shadows with as little noise as possible. We use a layered approach in the shadow map and reproject samples along the average motion vector, and then perform lookups in this representation. Our results include substantially improved shadow quality compared to previous work and a
Abstract in UndeterminedIn this article, we present a constraint programming approach for solving hard design problems present when automatically designing specialized processor extensions. Specifically, we discuss our approach for automatic selection and synthesis of processor extensions as well as efficient application compilation for these newly generated extensions. The discussed approach is i
Absorption and impedance mismatch due to the proximity of a user as well as certain propagation channel characteristics can severely degrade the multiple-input multiple-output (MIMO) performance of multi-antenna terminals in real usage scenarios. In this context, we investigated the potential of adaptive impedance matching (AIM) to mitigate performance degradation from these effects based on chann
In this paper, we describe a concise method for the feature-based representation of regions in an indoor environment and show how it can also be applied for door-passage-independent detection of transitions between regions to improve communication with a human user.
We consider the problem of approximating a given function in two dimensions by a sum of exponential functions, with complex-valued exponents and coefficients. In contrast to Fourier representations where the exponentials are fixed, we consider the nonlinear problem of choosing both the exponents and coefficients. In this way we obtain accurate approximations with only few terms. Our approach is bu
In this paper, we derive compact representations of the depth function for a triangle undergoing motion or defocus blur. Unlike a static primitive, where the depth function is planar, the depth function is a rational function in time and the lens parameters. Furthermore, we show how these compact depth functions can be used to design an efficient depth buffer compressor/decompressor, which signifi
In this paper, we present a meshing scheme for the implementation of an adaptive tessellation of triangular meshes on the graphics processing unit (GPU). Tessellation is performed according to a local test to generate primitives dynamically. The refinement procedure does not require the pre-computation of any refinement pattern. The resulting adaptive procedure is efficient and simple, and generat
We present user-controllable and plausible defocus blur for a stochastic rasterizer. We modify circle of confusion coefficients per vertex to express more general defocus blur, and show how the method can be applied to limit the foreground blur, extend the in-focus range, simulate tilt-shift photography, and specify per-object defocus blur. Furthermore, with two simplifying assumptions, we show th
This paper describes experiments to extract discourse relations holding between two text spans in Swedish. We considered three relation types: cause-explanation-evidence (CEV), contrast, and elaboration and we extracted word pairs eliciting these relations. We determined a list of Swedish cue phrases marking explicitly the relations and we learned the word pairs automatically from a corpus of 60 m
We herein formulate the concept of a generalized lock-in amplifier for the precision measurement of high frequency signals based on digital cavities. Accurate measurement of signals higher than 200 MHz using the generalized lock-in is demonstrated. The technique is compared with a traditional lock-in and its advantages and limitations are discussed. We also briefly point out how the generalized lo
Stereoscopic rendering and 3D stereo displays are quickly becoming mainstream. The natural extension is autostereoscopic multi-view displays, which by the use of parallax barriers or lenticular lenses, can accommodate many simultaneous viewers without the need for active or passive glasses. As these displays, for the foreseeable future, will support only a rather limited number of views, there is
Recent work has shown that, with the help of the Theory of Characteristic Modes (TCM), minor modifications of the terminal chassis can facilitate the design of orthogonal MIMO antennas with viable bandwidth at frequencies below 1 GHz. Herein, a new framework is proposed to further exploit TCM to enhance the performance of the orthogonal MIMO antennas. By correlating the characteristic currents and
High-quality video is being increasingly delivered over Internet Protocol networks, which means that network operators and service providers need methods to measure the quality of experience (QoE) of the video services. In this paper, we propose a method to speed up the development of no-reference bitstream objective metrics for estimating QoE. This method uses full-reference objective metrics, wh
Airborne dispersal of microalgae has largely been a blind spot in environmental biological studies because of their low concentration in the atmosphere and the technical limitations in investigating microalgae from air samples. Recent studies show that airborne microalgae can survive air transportation and interact with the environment, possibly influencing their deposition rates. This minireview
Abstract in UndeterminedThis article presents the development to reliably seal copper canisters containing the Swedish nuclear waste, using friction stir welding. To avoid defects and welding tool fractures, it is important to control the welding temperature within a span of 790–910 degrees C. A cascade controller is used to efficiently suppress fast power input disturbances reducing their impact on the temperature. The
As custom multicore architectures become more and more common for DSP applications, instruction selection and scheduling for such applications and architectures become important topics. In this paper, we explore the effects of defining the problem of finding an optimal instruction selection and scheduling as a constraint satisfaction problem (CSP). We incorporate methods based on sub-graph isomorp
