83 research outputs found

    Design of digital IP block for discrete cosine transform

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    Tato diplomová práce se zabývá návrhem IP bloku pro diskrétní kosinovou transformaci. V~teoretické části jsou shrnuty algoritmy pro výpočet diskrétní kosinové transformace a diskutována jejich použitelnost v~hardwaru. Zvolený algoritmus pro hardwarovou implementaci je modelován v jazyce C. Poté je popsán na RTL úrovni, verifikován a je provedena syntéza v~technologii TSMC 65 nm. Hardwarová implementace je poté zhodnocena s ohledem na datovou propustnost, plochu, rychlost and spotřebu.This diploma thesis deals with design of IP block for discrete cosine transform. Theoretical part summarizes algorithms for computation of discrete cosine transform and their hardware usability is discussed. Chosen algorithm for hardware implementation is modeled in C language. Algorithm is described at RTL level, verified and synthesized to TSMC 65 nm technology. Hardware implementation is then evaluated with respect of throughput, area, speed and power consumption.

    Low Complexity Image Recognition Algorithms for Handheld devices

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    Content Based Image Retrieval (CBIR) has gained a lot of interest over the last two decades. The need to search and retrieve images from databases, based on information (“features”) extracted from the image itself, is becoming increasingly important. CBIR can be useful for handheld image recognition devices in which the image to be recognized is acquired with a camera, and thus there is no additional metadata associated to it. However, most CBIR systems require large computations, preventing their use in handheld devices. In this PhD work, we have developed low-complexity algorithms for content based image retrieval in handheld devices for camera acquired images. Two novel algorithms, ‘Color Density Circular Crop’ (CDCC) and ‘DCT-Phase Match’ (DCTPM), to perform image retrieval along with a two-stage image retrieval algorithm that combines CDCC and DCTPM, to achieve the low complexity required in handheld devices are presented. The image recognition algorithms run on a handheld device over a large database with fast retrieval time besides having high accuracy, precision and robustness to environment variations. Three algorithms for Rotation, Scale, and Translation (RST) compensation for images were also developed in this PhD work to be used in conjunction with the two-stage image retrieval algorithm. The developed algorithms are implemented, using a commercial fixed-point Digital Signal Processor (DSP), into a device, called ‘PictoBar’, in the domain of Alternative and Augmentative Communication (AAC). The PictoBar is intended to be used in the field of electronic aid for disabled people, in areas like speech rehabilitation therapy, education etc. The PictoBar is able to recognize pictograms and pictures contained in a database. Once an image is found in the database, a corresponding associated speech message is played. A methodology for optimal implementation and systematic testing of the developed image retrieval algorithms on a fixed point DSP is also established as part of this PhD work

    Image Processing Using FPGAs

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    This book presents a selection of papers representing current research on using field programmable gate arrays (FPGAs) for realising image processing algorithms. These papers are reprints of papers selected for a Special Issue of the Journal of Imaging on image processing using FPGAs. A diverse range of topics is covered, including parallel soft processors, memory management, image filters, segmentation, clustering, image analysis, and image compression. Applications include traffic sign recognition for autonomous driving, cell detection for histopathology, and video compression. Collectively, they represent the current state-of-the-art on image processing using FPGAs

    Design Techniques for Energy-Quality Scalable Digital Systems

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    Energy efficiency is one of the key design goals in modern computing. Increasingly complex tasks are being executed in mobile devices and Internet of Things end-nodes, which are expected to operate for long time intervals, in the orders of months or years, with the limited energy budgets provided by small form-factor batteries. Fortunately, many of such tasks are error resilient, meaning that they can toler- ate some relaxation in the accuracy, precision or reliability of internal operations, without a significant impact on the overall output quality. The error resilience of an application may derive from a number of factors. The processing of analog sensor inputs measuring quantities from the physical world may not always require maximum precision, as the amount of information that can be extracted is limited by the presence of external noise. Outputs destined for human consumption may also contain small or occasional errors, thanks to the limited capabilities of our vision and hearing systems. Finally, some computational patterns commonly found in domains such as statistics, machine learning and operational research, naturally tend to reduce or eliminate errors. Energy-Quality (EQ) scalable digital systems systematically trade off the quality of computations with energy efficiency, by relaxing the precision, the accuracy, or the reliability of internal software and hardware components in exchange for energy reductions. This design paradigm is believed to offer one of the most promising solutions to the impelling need for low-energy computing. Despite these high expectations, the current state-of-the-art in EQ scalable design suffers from important shortcomings. First, the great majority of techniques proposed in literature focus only on processing hardware and software components. Nonetheless, for many real devices, processing contributes only to a small portion of the total energy consumption, which is dominated by other components (e.g. I/O, memory or data transfers). Second, in order to fulfill its promises and become diffused in commercial devices, EQ scalable design needs to achieve industrial level maturity. This involves moving from purely academic research based on high-level models and theoretical assumptions to engineered flows compatible with existing industry standards. Third, the time-varying nature of error tolerance, both among different applications and within a single task, should become more central in the proposed design methods. This involves designing “dynamic” systems in which the precision or reliability of operations (and consequently their energy consumption) can be dynamically tuned at runtime, rather than “static” solutions, in which the output quality is fixed at design-time. This thesis introduces several new EQ scalable design techniques for digital systems that take the previous observations into account. Besides processing, the proposed methods apply the principles of EQ scalable design also to interconnects and peripherals, which are often relevant contributors to the total energy in sensor nodes and mobile systems respectively. Regardless of the target component, the presented techniques pay special attention to the accurate evaluation of benefits and overheads deriving from EQ scalability, using industrial-level models, and on the integration with existing standard tools and protocols. Moreover, all the works presented in this thesis allow the dynamic reconfiguration of output quality and energy consumption. More specifically, the contribution of this thesis is divided in three parts. In a first body of work, the design of EQ scalable modules for processing hardware data paths is considered. Three design flows are presented, targeting different technologies and exploiting different ways to achieve EQ scalability, i.e. timing-induced errors and precision reduction. These works are inspired by previous approaches from the literature, namely Reduced-Precision Redundancy and Dynamic Accuracy Scaling, which are re-thought to make them compatible with standard Electronic Design Automation (EDA) tools and flows, providing solutions to overcome their main limitations. The second part of the thesis investigates the application of EQ scalable design to serial interconnects, which are the de facto standard for data exchanges between processing hardware and sensors. In this context, two novel bus encodings are proposed, called Approximate Differential Encoding and Serial-T0, that exploit the statistical characteristics of data produced by sensors to reduce the energy consumption on the bus at the cost of controlled data approximations. The two techniques achieve different results for data of different origins, but share the common features of allowing runtime reconfiguration of the allowed error and being compatible with standard serial bus protocols. Finally, the last part of the manuscript is devoted to the application of EQ scalable design principles to displays, which are often among the most energy- hungry components in mobile systems. The two proposals in this context leverage the emissive nature of Organic Light-Emitting Diode (OLED) displays to save energy by altering the displayed image, thus inducing an output quality reduction that depends on the amount of such alteration. The first technique implements an image-adaptive form of brightness scaling, whose outputs are optimized in terms of balance between power consumption and similarity with the input. The second approach achieves concurrent power reduction and image enhancement, by means of an adaptive polynomial transformation. Both solutions focus on minimizing the overheads associated with a real-time implementation of the transformations in software or hardware, so that these do not offset the savings in the display. For each of these three topics, results show that the aforementioned goal of building EQ scalable systems compatible with existing best practices and mature for being integrated in commercial devices can be effectively achieved. Moreover, they also show that very simple and similar principles can be applied to design EQ scalable versions of different system components (processing, peripherals and I/O), and to equip these components with knobs for the runtime reconfiguration of the energy versus quality tradeoff

    Design and implementation of camera module

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    Cílem diplomové práce je navrhnout levný, avšak dostatečně výkonný a univerzální systém, schopný snímání a zpracování obrazu z digitální kamery. Další částí je návrh a implementace funkcí pro zpracování obrazu a komunikace s nadřazeným systémem.Master thesis is aimed on the design of cheap and universal system, but also powerful enough to be able to obtain and process images from the digital camera sensor. Further part of the work is design and implementation of functions for image processing applications and communication with superior system.

    A robust hardware algorithm for real-time object tracking in video sequences

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    Abstract Most of the emerging content-based multimedia technologies are based on efficient methods to solve machine early vision tasks. Among other tasks, object segmentation is perhaps the most important problem in single image processing. The solution of this problem is the key technology of the development of the majority of leading-edge interactive video communication technology and telepresence systems. The aim of this paper is to present a robust framework for real-time object segmentation and tracking in video sequences taken simultaneously from different perspectives. The other contribution of the paper is to present a new dedicated parallel hardware architecture. It is composed of a mixture of Digital Signal Processing and Field Programmable Gate Array technologies and uses the Content Addressable Memory as a main processing unit. Experimental results indicate that small amount of hardware can deliver real-time performance and high accuracy. This is an improvement over previous systems, where execution time of the second-order using a greater amount of hardware has been proposed.

    High-precision grasping and placing for mobile robots

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    This work presents a manipulation system for multiple labware in life science laboratories using the H20 mobile robots. The H20 robot is equipped with the Kinect V2 sensor to identify and estimate the position of the required labware on the workbench. The local features recognition based on SURF algorithm is used. The recognition process is performed for the labware to be grasped and for the workbench holder. Different grippers and labware containers are designed to manipulate different weights of labware and to realize a safe transportation

    Implementation of BMA based motion estimation hardware accelerator in HDL

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    Motion Estimation in MPEG (Motion Pictures Experts Group) video is a temporal prediction technique. The basic principle of motion estimation is that in most cases, consecutive video frames will be similar except for changes induced by objects moving within the frames. Motion Estimation performs a comprehensive 2-dimensional spatial search for each luminance macroblock (16x16 pixel block). MPEG does not define how this search should be performed. This is a detail that the system designer can choose to implement in one of many possible ways. It is well known that a full, exhaustive search over a wide 2-dimensional area yields the best matching results in most cases, but this performance comes at an extreme computational cost to the encoder. Some lower cost encoders might choose to limit the pixel search range, or use other techniques usually at some cost to the video quality which gives rise to a trade-off; Such algorithms used in image processing are generally computationally expensive. FPGAs are capable of running graphics algorithms at the speed comparable to dedicated graphics chips. At the same time they are configurable through high-level programming languages, e.g. Verilog, VHDL. The work presented entirely focuses upon a Hardware Accelerator capable of performing Motion Estimation, based upon Block Matching Algorithm. The SAD based Full Search Motion Estimation coded using Verilog HDL, relies upon a 32x32 pixel search area to find the best match for single 16x16 macroblock; Keywords. Motion Estimation, MPEG, macroblock, FPGA, SAD, Verilog, VHDL

    Design And Implementation Of An Omnidirectional Mobile Robot Platform

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    Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2008Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2008Bu çalısmada robotik alanında yapılan akademik çalısmaların genis bir bölümünde uygulama gelistirme platformu olarak kullanılmak üzere; gerekli islemci gücü, algılama yetileri, hareket kabiliyeti ve iletisim altyapılarını sunan bir mobil robot platform tasarlanmıs ve gerçeklenmistir. Gerçeklenen robotun tabanı, iki diferansiyel sürümlü platformun üzerine sabitlenmistir. Bu sayede serbestlik derecesi dört olan taban, diferansiyel sürümlü platformları kontrol ederek her yöne hareket edebilme yeteneğine sahiptir. Gerçeklenen mekanik tasarımda, odometri tabanlı hassas konumlandırmanın mümkün olabilmesi için, robotun tasarımının kendine has geometrik avantajlarını kullanarak odometri hatalarının azaltılmasına olanak veren bir yöntem sunulmustur. Hareketli platformun üzerindeki donanım bataryalar, üç eksende hareketli bir kamera, çift çekirdekli bir DSP sistemi, Linux tabanlı bir kontrol kartı, kablosuz ağ ve video bağlantısı, grafik LCD ve detayları sunulmus olan, iki eksende hareketli bir lazer isaretçi ile kameranın kullanıldığı, çalısmaya özel olarak gelistirilmis üç boyutlu mesafe ölçerinden olusmaktadır.In this study, an omnidirectional mobile robot with sufficient processing power, sensory units and communication facilities for being utilized as an application development platform for a wide range of academic research in the field of robotics was designed and implemented. The base plane of the robot is attached onto two differential drive platforms, giving four-degrees-of-freedom to the base. This makes the robot able to move to any direction with proper control of the differential drive platforms, giving the property of omnidirectionality. A method to reduce odometric errors and make odometry based accurate positioning possible was also presented which utilizes the geometrical advantages particular to the robot’s mechanic design. The hardware on the moving base consists of batteries, a camera moving in three axes, a dual core DSP system, a Linux based control card, wireless network and video connection, graphical LCD and a laser pointer moving in two axes. An algorithm that uses the laser and the camera to obtain three dimensional distance measurements was also derived.Yüksek LisansM.Sc
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