68 research outputs found

    A high performance hardware architecture for one bit transform based motion estimation

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    Motion Estimation (ME) is the most computationally intensive part of video compression and video enhancement systems. One bit transform (IBT) based ME algorithms have low computational complexity. Therefore, in this paper, we propose a high performance systolic hardware architecture for IBT based ME. The proposed hardware performs full search ME for 4 Macroblocks in parallel and it is the fastest IBT based ME hardware reported in the literature. In addition, it uses less on-chip memory than the previous IBT based ME hardware by using a novel data reuse scheme and memory organization. The proposed hardware is implemented in Verilog HDL. It consumes %34 of the slices in a Xilinx XC2VP30-7 FPGA. It works at 115 MHz in the same FPGA and is capable of processing 50 1920x1080 full High Definition frames per second. Therefore, it can be used in consumer electronics products that require real-time video processing or compression

    Efficient hardware implementations of high throughput SHA-3 candidates keccak, luffa and blue midnight wish for single- and multi-message hashing

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    In November 2007 NIST announced that it would organize the SHA-3 competition to select a new cryptographic hash function family by 2012. In the selection process, hardware performances of the candidates will play an important role. Our analysis of previously proposed hardware implementations shows that three SHA-3 candidate algorithms can provide superior performance in hardware: Keccak, Luffa and Blue Midnight Wish (BMW). In this paper, we provide efficient and fast hardware implementations of these three algorithms. Considering both single- and multi-message hashing applications with an emphasis on both speed and efficiency, our work presents more comprehensive analysis of their hardware performances by providing different performance figures for different target devices. To our best knowledge, this is the first work that provides a comparative analysis of SHA-3 candidates in multi-message applications. We discover that BMW algorithm can provide much higher throughput than previously reported if used in multi-message hashing. We also show that better utilization of resources can increase speed via different configurations. We implement our designs using Verilog HDL, and map to both ASIC and FPGA devices (Spartan3, Virtex2, and Virtex 4) to give a better comparison with those in the literature. We report total area, maximum frequency, maximum throughput and throughput/area of the designs for all target devices. Given that the selection process for SHA3 is still open; our results will be instrumental to evaluate the hardware performance of the candidates

    High performance hardware architectures for one bit transform based motion estimation

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    Motion Estimation (ME) is the most computationally intensive and most power consuming part of video compression and video enhancement systems. ME is used in video compression standards such as MPEG4, H.264 and it is used in video enhancement algorithms such as frame rate conversion and de-interlacing. One bit transform (1BT) based ME algorithms have low computational complexity. Therefore, in this thesis, we propose high performance hardware architectures for 1BT based fixed block size (FBS) single reference frame (SRF) ME, variable block size (VBS) SRF ME, and multiple reference frame (MRF) ME. Constraint One Bit Transform (C-1BT) ME algorithm improves the ME performance of 1BT ME, and the early terminated C-1BT ME algorithm reduces the computational complexity of C-1BT ME. Therefore, in this thesis, we also propose a high performance early terminated C-1BT ME hardware architecture. The proposed FBS SRF ME hardware architectures perform full search ME for 4 Macroblocks in parallel and they are faster than the 1BT based ME hardware reported in the literature. In addition, they use less on-chip memory than the previous 1BT based ME hardware by using a novel data reuse scheme and memory organization. The proposed VBS SRF ME and MRF ME hardware architectures are the first 1BT based VBS ME and MRF ME hardware architectures in the literature. The proposed MRF ME hardware is designed as reconfigurable in order to statically configure the number and selection of reference frames based on the application requirements. The proposed early terminated C-1BT ME hardware architecture is the first early terminated C-1BT ME hardware architecture in the literature. All of the proposed ME hardware architectures are implemented in Verilog HDL and mapped to Xilinx FPGAs. All FPGA implementations are verified with post place & route simulations

    Real-Time High-Resolution Multiple-Camera Depth Map Estimation Hardware and Its Applications

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    Depth information is used in a variety of 3D based signal processing applications such as autonomous navigation of robots and driving systems, object detection and tracking, computer games, 3D television, and free view-point synthesis. These applications require high accuracy and speed performances for depth estimation. Depth maps can be generated using disparity estimation methods, which are obtained from stereo matching between multiple images. The computational complexity of disparity estimation algorithms and the need of large size and bandwidth for the external and internal memory make the real-time processing of disparity estimation challenging, especially for high resolution images. This thesis proposes a high-resolution high-quality multiple-camera depth map estimation hardware. The proposed hardware is verified in real-time with a complete system from the initial image capture to the display and applications. The details of the complete system are presented. The proposed binocular and trinocular adaptive window size disparity estimation algorithms are carefully designed to be suitable to real-time hardware implementation by allowing efficient parallel and local processing while providing high-quality results. The proposed binocular and trinocular disparity estimation hardware implementations can process 55 frames per second on a Virtex-7 FPGA at a 1024 x 768 XGA video resolution for a 128 pixel disparity range. The proposed binocular disparity estimation hardware provides best quality compared to existing real-time high-resolution disparity estimation hardware implementations. A novel compressed-look up table based rectification algorithm and its real-time hardware implementation are presented. The low-complexity decompression process of the rectification hardware utilizes a negligible amount of LUT and DFF resources of the FPGA while it does not require the existence of external memory. The first real-time high-resolution free viewpoint synthesis hardware utilizing three-camera disparity estimation is presented. The proposed hardware generates high-quality free viewpoint video in real-time for any horizontally aligned arbitrary camera positioned between the leftmost and rightmost physical cameras. The full embedded system of the depth estimation is explained. The presented embedded system transfers disparity results together with synchronized RGB pixels to the PC for application development. Several real-time applications are developed on a PC using the obtained RGB+D results. The implemented depth estimation based real-time software applications are: depth based image thresholding, speed and distance measurement, head-hands-shoulders tracking, virtual mouse using hand tracking and face tracking integrated with free viewpoint synthesis. The proposed binocular disparity estimation hardware is implemented in an ASIC. The ASIC implementation of disparity estimation imposes additional constraints with respect to the FPGA implementation. These restrictions, their implemented efficient solutions and the ASIC implementation results are presented. In addition, a very high-resolution (82.3 MP) 360°x90° omnidirectional multiple camera system is proposed. The hemispherical camera system is able to view the target locations close to horizontal plane with more than two cameras. Therefore, it can be used in high-resolution 360° depth map estimation and its applications in the future

    Dynamically variable step search motion estimation algorithm and a dynamically reconfigurable hardware for its implementation

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    Motion Estimation (ME) is the most computationally intensive part of video compression and video enhancement systems. For the recently available High Definition (HD) video formats, the computational complexity of De full search (FS) ME algorithm is prohibitively high, whereas the PSNR obtained by fast search ME algorithms is low. Therefore, ill this paper, we present Dynamically Variable Step Search (DVSS) ME algorithm for Processing high definition video formats and a dynamically reconfigurable hardware efficiently implementing DVSS algorithm. The architecture for efficiently implementing DVSS algorithm. The simulation results showed that DVSS algorithm performs very close to FS algorithm by searching much fewer search locations than FS algorithm and it outperforms successful past search ME algorithms by searching more search locations than these algorithms. The proposed hardware is implemented in VHDL and is capable, of processing high definition video formats in real time. Therefore, it can be used in consumer electronics products for video compression, frame rate up-conversion and de-interlacing(1)

    ANXIETY AND POST-TRAUMATIC STRESS DISORDER SYMPTOMS IN PREGNANT WOMEN DURING THE COVID-19 PANDEMIC’S DELAY PHASE

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    Background: The Coronavirus disease 2019 (COVID-19) pandemic emerged in Wuhan, China and has spread all over the world and affected global mental health. Pregnant women may be particularly vulnerable and experience high levels of distress during an infectious disease outbreak. The aim of this study was to determine anxiety and post-traumatic stress disorder (PTSD) symptoms in pregnant women during the COVID-19 pandemic. Subjects and methods:This cross-sectional study surveyed a total of 283 pregnant women within the period of May 11 to May 28,2020. During their regular antenatal visit, pregnant women were invited to participate in the study. The self-created personal information form was used to assess the main characteristics of the participants. Anxiety and PTSD symptoms of the pregnant women were measured by the Spielberger State-Trait Anxiety Inventory (STAI) and Impact of Events Scale-Revised (IES-R), respectively. Results: The mean age of the pregnant women was 29.20±5.55 years. Regarding gestational age, 72 (25.4%), 86 (30.4) and 125 (44.2) were in the first, second and third trimesters, respectively. The mean gestational age was 23.82±11.05 weeks. The mean STAIS and STAI-T scores were 39.52±10.56 within the cut-off value (39-40) of the instrument and 42.74±8.33, respectively. Furthermore, the mean total IES-R score was 36.60±15.65 within the cut-off value (24) of the instrument. Multiple regression analysis revealed that pregnancy complication (p=0.01) and employment status of husband (p=0.04) were the best predictors of state anxiety. Additionally, the presence of COVID-19-related symptoms (p=0.01) and educational level (p=0.01) were found to predict PTSD symptoms. Conclusions: Pregnant women would be likely to experience high levels of anxiety and PTSD symptoms during the COVID-19 pandemic’s delay phase. The results should sensitize the medical team to increased anxiety and PTDS symptoms of the pregnant women in order to prevent negative outcomes for women and their fetuses

    Rapid flipping of parametric phase states

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    Since the invention of the solid-state transistor, the overwhelming majority of computers followed the von Neumann architecture that strictly separates logic operations and memory. Today, there is a revived interest in alternative computation models accompanied by the necessity to develop corresponding hardware architectures. The Ising machine, for example, is a variant of the celebrated Hopfield network based on the Ising model. It can be realized with artifcial spins such as the `parametron' that arises in driven nonlinear resonators. The parametron encodes binary information in the phase state of its oscillation. It enables, in principle, logic operations without energy transfer and the corresponding speed limitations. In this work, we experimentally demonstrate flipping of parametron phase states on a timescale of an oscillation period, much faster than the ringdown time \tau that is often (erroneously) deemed a fundamental limit for resonator operations. Our work establishes a new paradigm for resonator-based logic architectures.Comment: 6 pages, 3 figure

    Dynamically adaptive real-time disparity estimation hardware using iterative refinement

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    The computational complexity of disparity estimation algorithms and the need of large size and bandwidth for the external and internal memory make the real-time processing of disparity estimation challenging, especially for High Resolution (HR) images. This paper proposes a hardware-oriented adaptive window size disparity estimation (AWDE) algorithm and its real-time reconfigurable hardware implementation that targets HR video with high quality disparity results. Moreover, an enhanced version of the AWDE implementation that uses iterative refinement (AWDE-IR) is presented. The AWDE and AWDE-IR algorithms dynamically adapt the window size considering the local texture of the image to increase the disparity estimation quality. The proposed reconfigurable hardware architectures of the AWDE and AWDE-IR algorithms enable handling 60 frames per second on a Virtex-5 FPGA at a 1024×768 XGA video resolution for a 128 pixel disparity range
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