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Scalable video coding using the Discrete Wavelet Transform : Skalbar videokodning med användning av den diskreta wavelettransformenJohansson, Gustaf January 2010 (has links)
<p>A method for constructing a highly scalable bit stream for video coding is presented in detail and implemented in a demo application with a GUI in the Windows Vista operating system.</p><p>The video codec uses the Discrete Wavelet Transform in both spatial and temporal directions together with a zerotree quantizer to achieve a highly scalable bit stream in the senses of quality, spatial resolution and frame rate.</p> / <p>I detta arbete presenteras en metod för att skapa en mycket skalbar videoström. Metoden implementeras sedan i sin helhet i programspråken C och C++ med ett grafiskt användargränssnitt på operativsystemet Windows Vista.</p><p>I metoden används den diskreta wavelettransformen i såväl de spatiella dimensionerna som tidsdimensionen tillsammans med en nollträdskvantiserare för att åstakomma en skalbar videoström i avseendena bildkvalitet, skärmupplösning och antal bildrutor per sekund.</p>
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Scalable video coding using the Discrete Wavelet Transform : Skalbar videokodning med användning av den diskreta wavelettransformenJohansson, Gustaf January 2010 (has links)
A method for constructing a highly scalable bit stream for video coding is presented in detail and implemented in a demo application with a GUI in the Windows Vista operating system. The video codec uses the Discrete Wavelet Transform in both spatial and temporal directions together with a zerotree quantizer to achieve a highly scalable bit stream in the senses of quality, spatial resolution and frame rate. / I detta arbete presenteras en metod för att skapa en mycket skalbar videoström. Metoden implementeras sedan i sin helhet i programspråken C och C++ med ett grafiskt användargränssnitt på operativsystemet Windows Vista. I metoden används den diskreta wavelettransformen i såväl de spatiella dimensionerna som tidsdimensionen tillsammans med en nollträdskvantiserare för att åstakomma en skalbar videoström i avseendena bildkvalitet, skärmupplösning och antal bildrutor per sekund.
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A Decision Support System for StressDiagnosis using ECG SensorIslam, Mohd. Siblee January 2010 (has links)
Diagnosis of stress is important because it can cause many diseases e.g., heart disease, headache, migraine, sleep problems, irritability etc. Diagnosis of stress in patients often involves acquisition of biological signals for example heart rate, finger temperature, electrocardiogram (ECG), electromyography signal (EMG), skin conductance signal (SC) etc. followed up by a careful analysis of the acquired signals. The accuracy is totally dependent on the experience of an expert. Again the number of such experts is also very limited. Heart rate is considered as an important parameter in determining stress. It reflects status of the autonomic nervous system (ANS) and thus is very effective in monitoring any imbalance in patient’s stress level. Therefore, a computer-aided system is useful to determine stress level based on various features that can be extracted from a patient’s heart rate signals. Stress diagnosis using biomedical signals is difficult and since the biomedical signals are too complex to generate any rule an experienced person or expert is needed to determine stress levels. Also, it is not feasible to use all the features that are available or possible to extract from the signal. So, relevant features should be chosen from the extracted features that are capable to diagnose stress. Again, ECG signal is frequently contaminated by outliers produced by the loose conduction of the electrode due to sneezing, itching etcetera that hampers the value of the features. A Case-Based Reasoning (CBR) System is helpful when it is really hard to formulate rule and the knowledge on the domain is also weak. A CBR system is developed to evaluate how closely it can diagnose stress levels compare to an expert. A study is done to find out mostly used features to reduce the number of features used in the system and in case library. A software prototype is developed that can collect ECG signal from a patient through ECG sensor and calculate Inter Beat Interval (IBI) signal and features from it. Instead of doing manual visual inspection a new way to remove outliers from the IBI signal is also proposed and implemented here. The case base has been initiated with 22 reference cases classified by an expert. A performance analysis has been done and the result considering how close the system can perform compare to the expert is presented. On the basis of the evaluations an accuracy of 86% is obtained compare to an expert. However, the correctly classified case for stressed group (Sensitivity) was 57% and it is quite important to increase as it is related to the safety issue of health. The reasons of relatively lower sensitivity and possible ways to improve it are also investigated and explained.
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Benchmarking of Sleipnir DSP Processor, ePUMA PlatformMurugesan, Somasekar January 2011 (has links)
Choosing a right processor for an embedded application, or designing a new pro-cessor requires us to know how it stacks up against the competition, or sellinga processor requires a credible communication about its performance to the cus-tomers, which means benchmarking of a processor is very important. They arerecognized world wide by processor vendors and customers alike as the fact-basedway to evaluate and communicate embedded processor performance. In this the-sis, the benchmarking of ePUMA multiprocessor developed by the Division ofComputer Engineering, ISY, Linköping University, Sweden will be described indetails. A number of typical digital signal processing algorithms are chosen asbenchmarks. These benchmarks have been implemented in assembly code withtheir performance measured in terms of clock cycles and root mean square errorwhen compared with result computed using double precision. The ePUMA multi-processor platform which comprises of the Sleipnir DSP processor and Senior DSPprocessor was used to implement the DSP algorithms. Matlab inbuilt models wereused as reference to compare with the assembly implementation to derive the rootmean square error values of different algorithms. The execution time for differentDSP algorithms ranged from 51 to 6148 clock cycles and the root mean squareerror values varies between 0.0003 to 0.11.
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Implementation of Video Codec System on ARM-based SoC Development PlatformLiu, Shu-You 30 July 2004 (has links)
In the last years, with more and more transistors can fit into a chip, the growth the IC design complexity is fast and original design flow can¡¦t cater for designers. Therefore, so many people promote to integrate the system into a single chip gradually with the last technology using the concept of hardware/software co-design. In this thesis, we use the hardware/software co-design concept to build a simple video codec from system level and implement it on the ARM¡¦s SOC platform. We focus on the hardware/software co-ordination. Because we use the platform-based design method, the build hardware/software modules can be used in the similar architecture on the ARM platform
In our Video codec system, discrete wavelet transform(DWT) and RGBtoYCbCr are the most timing-consuming parts. Since DWT has inherent scalability and excellent features of energy compaction, it has been applied widely in the various image compression systems. We adopt the 5-3 filter lifting-based DWT in the hardware part of our system and design three different lifting-based DWT architectures by using the high level synthesis concept to optimize the hardware utilization and speed. In the premise of not increasing memory access times and additional processes of software, we overcome the boundary extension of DWT and verify it by means of FPGA after combining it with the RGBtoYCbCr hardware architecture. Finally, the hardware part is integrated with the other part implemented by software, we build a completely video encode system on the ARM SOC platform using the hardware/software co-design.
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Transform-Domain Adaptive Constrained Filtering Algorithms for Time Delay EstimationHou, Jui-Hsiang 27 June 2002 (has links)
The convergence speed using the conventional approaches, viz., time-domain adaptive constrained and unconstrained LMS algorithms, becomes slowly, when dealing with the correlated source signals. In consequence, the performance of time delay estimation (TDE) will be degraded, dramatically. To improve this problem, the so-called transform-domain adaptive constrained filtering scheme, i.e., the adaptive constrained discrete-cosine-transform (DCT) LMS algorithm, has been proposed in [15]. However, the use of any one orthogonal transform will not result in a completely diagonal the input signal auto-correlation matrix for all types of input signals. In fact, the significant non-diagonal entries in the transform-domain auto-correlation matrix, will deteriorate the convergence performance of the algorithm.
To further overcome the problem described above, in this thesis, a modified approach, referred as the adaptive constrained modified DCT-LMS (CMDCT-LMS) algorithm, is devised for TDE under a wide class of input processes. In addition, based on the orthogonal discrete wavelet transform (DWT), an adaptive constrained modified DMT-LMS (CMDWT-LMS) algorithm is also devised and applied to the problem of TDE. We show that the proposed two modified constrained approaches for TDE does perform well than the unmodified approaches under different source signal models. Moreover, the adaptive CMDCT-LMS filtering algorithm does perform slightly better than the adaptive CMDWT-LMS filtering algorithm as observed from the simulation results.
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Komprese genomických signálů pro klasifikaci a identifikaci organismů / The use of genomic signal compression for classification and identification of organismsSedlář, Karel January 2013 (has links)
Modern classification of organisms is performed on molecular data. These methods rely on multiple alignment of sequences of characters which make them computationally demanding. Only small parts of genomes can be compared in reasonable time. In this paper, the novel algorithm based on conversion of the whole genome sequences to cumulative phase signals is presented. Dyadic wavelet transform is used for lossy compression of signals by redundant frequency bands elimination. Signal classification is then performed as a cluster analysis using Euclidian metrics where multiple alignment is replaced by dynamic time warping.
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Pokročilé metody pro zabezpečení multimediálních dat / Advanced Methods to Multimedia Data ProtectionMikulčík, Ondřej January 2014 (has links)
To protect the the copyright of multimedia works have been developed watermarking techniques, that insert an invisible watermark to the original data. The aim of this thesis was to explore modern watermarking techniques, choose three of them and realize them. Also test them, evaluate their properties and possibly improve them. All methods insert a watermark into luminance component of the original image, and work with binary or black and white watermark. All techniques work in the frequency domain using discrete wavelet transform. For the implementation of methods, have been developed software named "Watermarking" that has been programmed in JAVA Version 7. The first chapter describes the types of watermarks, the general process of insertion and extraction, watermarking systems and important feature requests of embedded water- marks. In addition, qualitative methods are mentioned for their comparisons and testing. The chapter also contains a theoretical description of the used transformations and functions. In the second chapter is described the user interface of the software "Water- marking". Chapters three and four contain a theoretical description of the implemented methods and description of implementation of insertion and extraction processes of the watermark. Also there are discussed the exact procedures for testing, the sample data, and the results which are clearly displayed in the tables. The fifth chapter discusses in detail the results obtained in testing the robustness of the watermark, using the software StirMark. In the conclusion are evaluated the advantages and disadvantages of methods and quality parameters.
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Automatisk metod för läs-screening i lågstadiet / Automated screening method for reading difficulties in lower schoolLindmark, Ada, Vos, Christian January 2020 (has links)
En av de mest centrala delarna av undervisningen i lågstadiet fokuserar på svenskämnet och speciellt elevers läsförmåga. Trots obligatoriska screeningmoment och nationella bedömningsstöd uppfattar personal inom skola att kartläggning av läskunskaper är tidskrävande, komplext och subjektivt till följd av dess manuella format. Denna studie undersöker hur en automatiserad läs-screening kan implementeras som ett kompletterande verktyg i lågstadiet genom forced alignment. Syftet är att fastställa om ett program är tillräckligt pålitligt för att underlätta screeningprocessen och tidigare kunna identifiera elever med lässvårigheter. Genom intervjuer med personer som jobbar inom skola och framtagandet av en prototyp har resultaten analyserats. Studiens slutsats blev att det finns fördelar med att komplettera den manuella läs-screeningen med ett automatiskt verktyg, men att det inte går att dra några slutsatser om huruvida verktyget går att implementera i samtliga skolor med positiva effekter. Det kan vara mer fördelaktigt att använda sig av ett automatiskt verktyg i mellanstadiet, men till följd av låg svarsfrekvens vid intervjuer kan detta inte fastställas. / One of the most central parts of the education in lower school is Swedish and especially reading skills. Even though there are mandatory screening moments and national evaluation support, employees in schools think of the screenings as a timeconsuming, complex, and subjective process due to their manual format. This study investigates how an automatized reading screening can be implemented in lower school as a complemental tool by forced alignment. The purpose is to confirm whether a program is reliable enough to make it easier to perform reading screening and earlier identify pupils with reading difficulties. By interviewing employees in schools and creating a prototype, the results have been analyzed. The study concluded was that there are advantages of having an automatic complementary tool in the reading screening process. Still, there was not possible to make any conclusions about whether the tool can be implemented in all schools with positive effects. It could be more beneficial to use an automatic tool in middle school, but due to low answering frequency, this cannot be established.
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Nocturnal Bird Call Recognition System for Wind Farm ApplicationsBastas, Selin A. 10 July 2012 (has links)
No description available.
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