14857874
Anti-aliasing and Continuity with Trapezoidal Shadow Maps
This paper proposes a new shadow map technique termed trapezoidal shadow maps to calculate high quality shadows in real-time applications. To address the resolution problem of the standard shadow map approach, our technique approximates the eye's frustum as seen from the light with a trapezoid to warp it onto a shadow map. Such a trapezoidal approximation, which may first seem straightforward, is carefully designed to achieve the goal of good shadow quality for objects from near to far, and to address the continuity problem that is found in all existing shadow map approaches. The continuity problem occurs mainly when the shadow map quality changes significantly from frame to frame due to the motion of the eye or the light. This results in flickering of shadows. On the whole, our proposed approach is simple to implement without using complex data structures and it maps well to graphics hardware as shown in our experiments with large virtual scenes of hundreds of thousands to over a million of triangles.
7171205
An optimal bound for high-quality conforming triangulations
AbstractThis paper shows that, for any plane geometric graph
$$\mathcal{G}$$
 withn vertices, there is a triangulation
$$\mathcal{T}$$
 that conforms to
$$\mathcal{G}$$
, i.e., each edge of
$$\mathcal{G}$$
 is the union of some edges of
$$\mathcal{T}$$
, where
$$\mathcal{T}$$
 hasO(n2) vertices with each angle of its triangles measuring no more than 11/15π. Additionally,
$$\mathcal{T}$$
 can be computed inO(n2 logn) time.
15339123
Utilizing jump flooding in image-based soft shadows
This paper studies the usage of the GPU as a collection of groups of related processing units, where each group communicates in some way to complete a computation efficiently and effectively. In particular, we use the GPU to perform jump flooding to pass information among groups of processing units in the design of two simple real-time soft shadow algorithms. These two algorithms are purely image-based in generating plausible soft shadows. Their computational costs depend mainly on the resolution of the shadow map or the screen. They run on an order of magnitude faster than existing comparable methods.
8559676
A simulation framework for energy-consumption analysis of OS-driven embedded applications
Energy consumption has become a major focus in the design of embedded systems (e.g., mobile computing and wireless communication devices). In particular, a shift of emphasis from hardware-oriented low-energy design techniques to energy-efficient embedded software design has occurred progressively in the past few years. To that end, various techniques have been developed for the design of energy-efficient embedded software. In operating system (OS)-driven embedded systems, the OS has a significant impact on the system's energy consumption directly (energy consumption associated with the execution of the OS functions and services), as well as indirectly (interaction of the OS with the application software). As a first step toward designing energy-efficient OS-based embedded systems, it is important to analyze the energy consumption of embedded software by taking the OS energy characteristics into account. To facilitate such studies, we present, in this work, an energy simulation framework that can be used to analyze the energy consumption characteristics of an embedded system featuring the embedded Linux OS running on the StrongARM processor. The framework allows software designers to study the energy consumption of the system software in relation to the application software, identify the energy hot spots, and perform design changes based on the knowledge of the OS energy consumption characteristics as well as application-OS interactions.
37912790
Asia Pacific Bioinformatics Network
3247302
An Energy-Aware Synthesis Methodology for OS-Driven Multi-Process Embedded Software
The growing software content in various battery-driven embedded systems has led to significant interest in technologies for energy-efficient embedded software. While lowenergy software research has, in the past, focused on energy optimization at the instruction and source-code levels, approaches targeted at a higher software level are beginning to gain attention. In this work, we propose a methodology to refine a control-data flow diagram (CDFD) model of an embedded software program into an energy-efficient multi-process software architecture graph (SAG). Our starting representation, the CDFD, is capable of modeling data-dependent control flow. Energy efficiency is achieved by reducing the energy wastage due to context switches and inter-process communications (IPCs). Conditionally-unused computational operations, and their corresponding energy, are also avoided by a condition-aware static scheduler. Finally, code generation is performed from the energy-efficient SAG to produce a multi-process program that implements the original CDFD specification. Experimental results establish the efficacy of the proposed approach.
1231228
Font Recognition Based on Global Texture Analysis
We describe a novel texture analysis-based approach toward font recognition. Existing methods are typically based on local typographical features that often require connected components analysis. In our method, we take the document as an image containing some specific textures and regard font recognition as texture identification. The method is content-independent and involves no detailed local feature analysis. Experiments are carried out by using 14000 samples of 24 frequently used Chinese fonts (six typefaces combined with four styles), as well as 32 frequently used English fonts (eight typefaces combined with four styles). An average recognition rate of 99.1 percent is achieved. Experimental results are also included on the robustness of the method against image degradation (e.g., pepper and salt noise) and on the comparison with existing methods.