Video encoders are an important IP block in mobile multimedia systems. In this paper, we describe a low-cost low-power multi-standard (MPEG4, JPEG, and H.263) video/image encoder. The low-cost and low-power aspects ar...
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Video encoders are an important IP block in mobile multimedia systems. In this paper, we describe a low-cost low-power multi-standard (MPEG4, JPEG, and H.263) video/image encoder. The low-cost and low-power aspects are achieved by the right choice of algorithms and architectures. In the algorithm front, an embedded compression technique for reducing the size of loop memory has enabled a single-chip low-cost realization of the encoder. Further, the hardware components that accelerate the kernels of encoding are implemented as application specific instruction-set processors (ASIPs) thereby providing flexibility to address multi-standard encoding. The power and area estimates for the encoder for QCIF@15fps in 0.18 /spl mu/m CMOS technology are 30 mW and 20 mm/sup 2/ respectively including the loop memory.
Summary form only given. The article describes a state-centric abstraction for application users to interact with sensor networks. Just as in data-centric routing and storage where physical nodes are less important th...
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ISBN:
(纸本)9781581137422
Summary form only given. The article describes a state-centric abstraction for application users to interact with sensor networks. Just as in data-centric routing and storage where physical nodes are less important than the data itself, state-centric abstraction introduces "states" as a natural vocabulary to describe spatio-temporal physical phenomena that the sensor networks are typically designed for. Application programmers specify the computation as creation, sharing and transformation of states, which naturally map to descriptions in signal processing and control applications. We argue that due to the dynamic nature of sensor networks, programs written in state-centric abstractions are more invariant to constant changes in data stream configurations and make the resulting software more portable across multiple sensor network platforms. With the help of models of sensor collaboration, sensing and estimation, the state-centric specifications are mapped into collaborative processing tasks at compile time, and further maintained at run time, leveraging the data-centric caching and routing services. We use a multi-target tracking system as an example to show how state-centric programming models can raise the abstraction level for users to interact with sensor networks and help modularize the design.
In the Sesame framework, we develop a modeling and simulation environment for the efficient design space exploration of heterogeneous embedded systems. Since Sesame recognizes separate application and architecture mod...
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ISBN:
(纸本)9781581137422
In the Sesame framework, we develop a modeling and simulation environment for the efficient design space exploration of heterogeneous embedded systems. Since Sesame recognizes separate application and architecture models within a single system simulation, it needs an explicit mapping step to relate these models for co-simulation. So far in Sesame, the mapping decision as been assumed to be made by an experienced designer, intuitively. However, this assumption is increasingly becoming inappropriate for the following reasons: already the realistic systems are far too complex for making intuitive decisions at an early design stage where the design space is very large. Likely, these systems will get even more complex in the near future. Besides, there exist multiple criteria to consider, like processing times, power consumption and cost of the architecture, which make the decision problem even harder. The mapping decision problem is formulated as a multiobjective combinatorial optimization problem. For a solution approach, an optimization software tool, implementing an evolutionary algorithm from the literature, has been developed to achieve a set of best alternative mapping decisions under multiple criteria. In a case study, we have used our optimization tool to obtain a set of mapping decisions, some of which were further evaluated by the Sesame simulation framework.
One of the most challenging problems in high-level synthesis is how to quickly explore a wide range of design options to achieve high-quality designs. This paper presents an Integrated Framework for Design Optimizatio...
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One of the most challenging problems in high-level synthesis is how to quickly explore a wide range of design options to achieve high-quality designs. This paper presents an Integrated Framework for Design Optimization and Space Minimization (IDOM) towards finding the minimum configuration satisfying timing and code size constraints. We show an effective way to reduce the design space to be explored through the study of the fundamental properties and relations among multiple design parameters, such as retiming value, unfolding factor, timing, and code size. Theories are presented to produce a small set of feasible design choices with provable quality. IDOM algorithm is proposed to generate high-quality design by integrating performance and code size optimization techniques. The experimental results on a set of DSP benchmarks show the efficiency and effectiveness of the IDOM algorithm. It constantly generates the minimal configuration for all the benchmarks. The cost of design space exploration using IDOM is only 3% of that using the standard method.
We describe our first efforts to develop a set of off-the-shelf hardware components that ordinary people could connect to build a simple but useful class of embedded systems. The class of systems, which we call monito...
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ISBN:
(纸本)9781581137422
We describe our first efforts to develop a set of off-the-shelf hardware components that ordinary people could connect to build a simple but useful class of embedded systems. The class of systems, which we call monitor/control systems, is composed primarily of sensors - light, motion, sound, contact, and other types - and output devices - light-emitting diodes, beeping speakers, or even electric relays that control electric appliances like lamps. For example, one monitor/control system would detect if a house's garage door was open at night, and would blink a LED inside the house to alert the homeowner this normally undesirable situation. Today, configuring even the most basic monitor/control system requires knowledge of electronics and programming. We seek to create a set of building blocks, which we call eBlocks, which would enable someone with no knowledge of electronics or programming to be able to build simple but useful monitor/control systems. We are creating eBlocks largely by incorporating intelligence into previously dumb sensors and output devices, and by developing a set of standards and methods that enable eBlocks to work together seamlessly when connected. eBlocks have only recently become possible due to the extremely low cost, low power, and small size of embedded microprocessors. We describe our first results of creating a basic class of eBlocks, Boolean eBlocks, that from a user's perspective transmit or receive only "yes" or "no" signals. We discuss the internal eBlock design, eBlock system design issues and decisions, and several eBlock-based systems designed by ourselves and by undergraduate students.
CAD vendors are always faced with the question of what tools to develop and how much can they charge for them. Designers on the other hand have real problems to solve and before investing in tools they have to assess ...
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CAD vendors are always faced with the question of what tools to develop and how much can they charge for them. Designers on the other hand have real problems to solve and before investing in tools they have to assess how much a given tool will actually save them. CAD vendors and designers have to estimate the savings in design time and cost that a tool may provide and compare that with the existing way of doing things, to determine if the investment in tool creation is justified. For example, if a misguided architectural decision causes weeks of delay because of missing performance targets, then a tool for early architectural analysis may be very valuable. system-level design poses exactly these types of questions because it involves optimizations and analyses across many domains, from software, to architecture, to cycle-time, and is done very early in the design cycle where it has a profound impact. This panel will bring together industry experts to review the current and future industry needs for system-level design technologies as well as discuss how much saving in design time and cost such tools can hope to achieve and whether the designers believe the price is right for the return they can get.
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