262,671 research outputs found

    FPGA applications in signal and image processing

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    The increasing demand for real-time and smart digital signal processing (DSP) systems, calls for a better platform for their implementation. Most of these systems (e.g. digital image processing) are highly parallelisable, memory and processor hungry; such that the increasing performance of today�s general-purpose microprocessors are no longer able to handle them. A highly parallel hardware architecture, which offers enough memory resources, offers an alternative for such DSP implementations

    Optical memory disks in optical information processing

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    We describe the use of optical memory disks as elements in optical information processing architectures. The optical disk is an optical memory devicew ith a storage capacity approaching 1010b its which is naturally suited to parallel access. We discuss optical disk characteristics which are important in optical computing systems such as contrast, diffraction efficiency, and phase uniformity. We describe techniques for holographic storage on optical disks and present reconstructions of several types of computer-generated holograms. Various optical information processing architectures are described for applications such as database retrieval, neural network implementation, and image correlation. Selected systems are experimentally demonstrated

    Parallel Image Processing Concepts

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    Image processing is a task of analysing the image and produces a resultant output in linear way. Image processing tasks are widely used in many applications domains, including medical imaging, industrial manufacturing, entertainment and security systems. Often the size of the image is very large, the processing time has to be very small and usually real-time constraints have to be met. The image analysis requires a large amount of memory and cpu performance, to cope this problem image processing task is parallelized. Parallelism of image analysis task becomes a key factor for processing a huge raw image data. Parallelization allows a scalable and flexible resource management and reduces a time for developing image analysis program. This paper presenting, the automatic parallelization of image processing task in a distributed system, in which suitable subtasks for parallel processing are extracted and mapped with the components of distributed system. This paper presents different design issues of parallel image processing in distributed system. Which helps the image analysis tasks that how to post processing the image in parallel. This technique is quite interactive especially when developing parallel program, as this requires little efforts for finding a suitable distribution of program module and data

    Synthetic aperture radar signal processing on the MPP

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    Satellite-borne Synthetic Aperture Radars (SAR) sense areas of several thousand square kilometers in seconds and transmit phase history signal data several tens of megabits per second. The Shuttle Imaging Radar-B (SIR-B) has a variable swath of 20 to 50 km and acquired data over 100 kms along track in about 13 seconds. With the simplification of separability of the reference function, the processing still requires considerable resources; high speed I/O, large memory and fast computation. Processing systems with regular hardware take hours to process one Seasat image and about one hour for a SIR-B image. Bringing this processing time closer to acquisition times requires an end-to-end system solution. For the purpose of demonstration, software was implemented on the present Massively Parallel Processor (MPP) configuration for processing Seasat and SIR-B data. The software takes advantage of the high processing speed offered by the MPP, the large Staging Buffer, and the high speed I/O between the MPP array unit and the Staging Buffer. It was found that with unoptimized Parallel Pascal code, the processing time on the MPP for a 4096 x 4096 sample subset of signal data ranges between 18 and 30.2 seconds depending on options

    Programmability and Performance of Parallel ECS-based Simulation of Multi-Agent Exploration Models

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    While the traditional objective of parallel/distributed simulation techniques has been mainly in improving performance and making very large models tractable, more recent research trends targeted complementary aspects, such as the “ease of programming”. Along this line, a recent proposal called Event and Cross State (ECS) synchronization, stands as a solution allowing to break the traditional programming rules proper of Parallel Discrete Event Simulation (PDES) systems, where the application code processing a specific event is only allowed to access the state (namely the memory image) of the target simulation object. In fact with ECS, the programmer is allowed to write ANSI-C event-handlers capable of accessing (in either read or write mode) the state of whichever simulation object included in the simulation model. Correct concurrent execution of events, e.g., on top of multi-core machines, is guaranteed by ECS with no intervention by the programmer, who is in practice exposed to a sequential-style programming model where events are processed one at a time, and have the ability to access the current memory image of the whole simulation model, namely the collection of the states of any involved object. This can strongly simplify the development of specific models, e.g., by avoiding the need for passing state information across concurrent objects in the form of events. In this article we investigate on both programmability and performance aspects related to developing/supporting a multi-agent exploration model on top of the ROOT-Sim PDES platform, which supports ECS

    Doctor of Philosophy

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    dissertationStochastic methods, dense free-form mapping, atlas construction, and total variation are examples of advanced image processing techniques which are robust but computationally demanding. These algorithms often require a large amount of computational power as well as massive memory bandwidth. These requirements used to be ful lled only by supercomputers. The development of heterogeneous parallel subsystems and computation-specialized devices such as Graphic Processing Units (GPUs) has brought the requisite power to commodity hardware, opening up opportunities for scientists to experiment and evaluate the in uence of these techniques on their research and practical applications. However, harnessing the processing power from modern hardware is challenging. The di fferences between multicore parallel processing systems and conventional models are signi ficant, often requiring algorithms and data structures to be redesigned signi ficantly for efficiency. It also demands in-depth knowledge about modern hardware architectures to optimize these implementations, sometimes on a per-architecture basis. The goal of this dissertation is to introduce a solution for this problem based on a 3D image processing framework, using high performance APIs at the core level to utilize parallel processing power of the GPUs. The design of the framework facilitates an efficient application development process, which does not require scientists to have extensive knowledge about GPU systems, and encourages them to harness this power to solve their computationally challenging problems. To present the development of this framework, four main problems are described, and the solutions are discussed and evaluated: (1) essential components of a general 3D image processing library: data structures and algorithms, as well as how to implement these building blocks on the GPU architecture for optimal performance; (2) an implementation of unbiased atlas construction algorithms|an illustration of how to solve a highly complex and computationally expensive algorithm using this framework; (3) an extension of the framework to account for geometry descriptors to solve registration challenges with large scale shape changes and high intensity-contrast di fferences; and (4) an out-of-core streaming model, which enables developers to implement multi-image processing techniques on commodity hardware

    Development and implementation of real time image analysis algorithms

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    This work concerns the development and implementation of real-time image processing algorithms. Such systems may be applied to industrial inspection problems, which typically require basic operations to be performed on 256 x 256 pixel images in 20 to 100ms using systems costing less than about &pound;20000.Building such systems is difficult because conventional processors executing at around 1MIPS with conventional algorithms are some 2 orders of magnitude too slow. A solution to this is to use a closely coupled array processor such as the DAP, or CLIP4 which is designed especially for image processing. However such a space-parallel architecture imposes its own structure on the problem, and this restricts the class of algorithms which may be efficiently executed to those exhibiting similar space parallelism, i.e. so-called 'parallel algorithms'. This thesis examines an alternative approach which uses a mix of conventional processors and high speed hardware processors. A special frame store has been built for the acquisition and display of images stored in memory on a multiprocessor backplane. Also described are an interface to a host mini-computer, a bus interface to the system and its use with some hardwired and microcoded processors. This system is compared to a single computer operating with a frame store optimised for image processing. The basic software and hardware system described in this thesis has been used in a factory environment for foodproduct inspection.<p
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