Yair Moshe, Hagit Hel‐Or · IEEE Transactions on Image Processing · 2009
Motion in modern video coders is estimated using a block matching algorithm that calculates the distance and direction of motion on a block-by-block basis. In this paper, a novel fast block-based motion estimation algorithm is proposed. This algorithm uses an efficient projection framework that bounds the distance between a template block and candidate blocks. Fast projection is performed using a family of highly efficient filter kernels--the gray-code kernels--requiring only 2 operations per pixel per kernel. The projection framework is combined with a rejection scheme which allows rapid rejection of candidate blocks that are distant from the template block. The tradeoff between computational complexity and quality of results can be easily controlled in the proposed algorithm; thus, it enables adaptivity to image content to further improve the results. Experiments show that the proposed adaptive algorithm outperforms other popular fast motion estimation algorithms.
Cited by 35
Ghassan M. Kraidy · 2016
In this work, we propose the construction of turbo codes for high rate transmission over block-fading channels. These codes are suitable for modern standards such as the 3GPP-LTE, in which high data rates are required. Our designs are based on channel multiplexing schemes initially developed for block fading channels, namely horizontal multiplexing and h-n-diagonal multiplexing. However, to attain the maximum diversity order provided by the channel for high-coding rates, a single parity-check code is needed in the overall code construction. Word error rate performance is compared to Gaussian and discrete outage probabilities using Monte Carlo simulations.
Cited by 3
K.L.V.Ramana Kumari, M. Asha Rani, N. Balaji et al. · 2018
Cited by 0
Andy Prasetyo, Siti Nur Aliyah · Zenodo (CERN European Organization for Nuclear Research) · 2018
The maximum and minimum values are the largest and smallest values of a function. The biggest value is called the maximum value, while the smallest value is called the minimum value. Several types of functions have maximum values at an interval. The maximum value for a function can be determined by several methods. In the journal entitled DETERMINING MAXIMUM VALUES WITH C ++ IN THE CODEBLOCK PROGRAM. This study uses a codeblock development method for user analysis, user needs analysis and system requirements analysis. There is a special feature that is about simulations where students can interact directly with the application by inputting data input directly, as well as a training menu that can provide maximum values. This program was made so that the calculation of finding the highest value can be done more effectively and efficiently on time. And the accuracy of the results is even more secure so that it is easier to implement the program into the related routines. Manually, it usually requires a lot of diligence and high concentration to find th highest value that sometimes occurs in hundreds to thousands of data so that it requires a lot of time and energy.
Cited by 0Open access
K. Meena Anusha, Ch. Santhi Rani · International Journal of Recent Technology and Engineering (IJRTE) · 2020
Over recent years, various modulation and coding techniques have been proposed in MIMO wireless communication systems. A MIMO system uses the concept of spatial diversity which is very successful and promising technique. When a coherent transmission system is considered, the estimation of radio channel impulse response is done precisely. In MIMO systems, the radio channel is estimated among every transmitting and receiving antennas such that the complexity can be increased. For this reason, in MIMO systems differential modulation schemes are estimated. A Differential Space-Time Block Code (DSTBC) is useful in the Raleigh fading channel as they do not require channel estimates. Space-time coding with MIMO antennas at transmitting and receiving reduces the consequences of fading in multiple paths and therefore the performance of digital transmission throughout wireless radio channel can be improved. So it has been presumed that perfect CSI is available at the receiver and coherent detection is employed. This paper presents improvement of Frame Error Rate (FER) for differential space-time block code using various Doppler spectra. When the channels estimates are not available the DSTBC system noticed that at SNR of 10 dB, for two transmitting and four receiving antennas the FER is 0.0067 for rounded Doppler spectrum. The differential schemes attains full transmit diversity owing to orthogonal designs. However, the receiver or the transmitter needs the channel state information so these differential schemes are 3 dB worse than the STBC with coherent detection.
Cited by 1Open access
Lu, Yao, Liu, Wanwei, Zhang, Tanghaoran et al. · ArXiv.org · 2025
Code differencing is a fundamental technique in software engineering practice and research. While researchers have proposed text-based differencing techniques capable of identifying line changes over the past decade, existing methods exhibit a notable limitation in identifying edit actions (EAs) that operate on text blocks spanning multiple lines. Such EAs are common in developers' practice, such as moving a code block for conditional branching or duplicating a method definition block for overloading. Existing tools represent such block-level operations as discrete sequences of line-level EAs, compelling developers to manually correlate them and thereby substantially impeding the efficiency of change comprehension. To address this issue, we propose BDiff, a text-based differencing algorithm capable of identifying two types of block-level EAs and five types of line-level EAs. Building on traditional differencing algorithms, we first construct a candidate set containing all possible line mappings and block mappings. Leveraging the Kuhn-Munkres algorithm, we then compute the optimal mapping set that can minimize the size of the edit script (ES) while closely aligning with the original developer's intent. To validate the effectiveness of BDiff, we selected five state-of-the-art tools, including large language models (LLMs), as baselines and adopted a combined qualitative and quantitative approach to evaluate their performance in terms of ES size, result quality, and running time. Experimental results show that BDiff produces higher-quality differencing results than baseline tools while maintaining competitive runtime performance. Our experiments also show the unreliability of LLMs in code differencing tasks regarding result quality and their infeasibility in terms of runtime efficiency. We have implemented a web-based visual differencing tool.
Cited by 0Open access
Yueqian Li, Masoud Salehi · 2010
We investigate quasi-cyclic low-density parity-check (QC-LDPC) codes for nonergodic block-fading channels. A construction method for designing QC-LDPC codes is presented. With careful design, the proposed QC-LDPC codes exhibit the same good performance as their corresponding random root- LDPC codes introduced in using iterative belief-propagation (BP) decoding. Moreover, the structure of the proposed QCLDPC codes makes an efficient encoding method possible.
Cited by 29
Prasetyo, Andy, Adami, Abu Nizzan · Zenodo (CERN European Organization for Nuclear Research) · 2018
Dividing inheritance into probelmatika in each region, because it is not yet understood by Islamic law about the distribution of inheritance. Therefore, this research was made to make it easier for people to use the C ++ language in the codeblock application. The results of this study are that the distribution of inheritance using C ++ based on codeblock is more efficient and does not cause conflicts between families, because it is according to shari'ah calculations.
Cited by 0Open access
Minghui Shi, Bailiang Li · 2012
Dual image watermarking algorithm based on block truncation code is proposed. In the algorithm, after the origin image is performed block truncation code and quad tree segmentation, the area of HF image and LF image could be obtained. The HF and LF image are decomposed using DWT. Moreover, the dual watermarks are performed an m-sequence transformation. Select LH coefficients and use SVD method. Embed the watermark into V component of the SVD domain. The dual watermark image can be got after the inverse SVD and DWT transformed. The experimental results demonstrate that the watermarking algorithm has good robustness against the attacks such as rotation, image compression, noise addition, filtering and other
Cited by 2
Sugamya Katta · International Journal for Research in Applied Science and Engineering Technology · 2021
A new approach is proposed to index images in database using features generated from the HODBTC compressed data stream. This indexing technique can be extended for CBIR. HODBTC compresses an image into a set of color quantizers and a bitmap image. The proposed image retrieval system generates two image features namely CCF and BPF from the minimum quantizer, maximum quantizer and bitmap image respectively by involving the visual codebook.
Cited by 0Open access
Vincent Choqueuse, K. Yao, Ludovic Collin et al. · IEEE Transactions on Wireless Communications · 2008
The blind recognition of communication parameters is a key research issue for commercial and military communication systems. The results of numerous investigations about symbol timing estimation, modulation recognition as well as identification of the number of transmitters have been reported in the literature. But, to our knowledge, none of them have dealt with the recognition of the Space-Time Block Codes (STBC) used in multiple transmitter communications. In order to blindly recognize the STBC of a wireless communication, this paper proposes a method based on the space-time correlations of the received signals. Under perfect timing synchronization and under ideal conditions (full rank channel and a number of receivers greater or equal to the number of transmitters), it shows that the Frobenius norms of these statistics present non-null values whose positions only depend on the STBC at the transmitter side. A classifier for the space-time code recognition of 5 linear STBC (Spatial Multiplexing, Alamouti Coding, and 3 Orthogonal STBC using 3 antennas) is presented. Simulations show that the proposed method performs well even at low signal-to-noise ratios.
Cited by 62
Prasetyo, Andy, Mujayanto, Mohammad · Zenodo (CERN European Organization for Nuclear Research) · 2018
Masyarakat menginginkan disediakanya berbagijenis layanan yang dapat di akses dengan berbagai cara secaramudah, cepat, efisien, dan tersedia 24 jam sehari , 7 hari dalam seminggu di manapun dan kapanpun.Sejak dulu hingga saat ini, penonton yang ingin membeli tiket harus mengantri di loket untuk membeli tiket bioskop.cara ini relatife tidak evektif karena penonton harus mengantri dalam antrian yang cukup panjang dan cukup lama untuk mendapatkan tiket bioskop, namun tidak jarang sebelum giliranya membeli tiket, tiket yang diingin kan sudah habis terjual tanpa ada informasi mengenai tiket yang masih tersedia. Solusi untuk memecahkan maalah itu adalah membuat system aplikasi ticketing berbasis web yang diharapkan dapat memudahkan masalah tersebut. pada system yang barupenonton dapat melihat film yang akan ditayangkan dibioskop, mendapatkan informasi harga tiket pada bioskop yang berbeda lokasinya, mendapatkan informasiketersediaan tiket dan lokasi tempat duduk, dan membeli tiket bioskop yang ingin ditontonnya melalui online
Cited by 0Open access
Gowtham Arjun, G. Fathima · International Journal of Innovative Research in Engineering · 2024
As we depend more and more on online platforms, keeping user login secure is a top priority. Traditional methods, which often store usernames and passwords on central servers, are increasingly at risk from cyberattacks like data breaches, phishing scams, and identity theft. To overcome these problems, this project suggests a decentralized login system based on block chain technology. Blockchain provides a secure and transparent record where login information are managed safely without a central authority. Smart contracts enable automated checks that are resistant to tampering and unauthorized access. Unlike standard systems, this approach eliminates the single point of failure by spreading data across a blockchain network, ensuring better uptime and security. Users have more control over their online identities because blockchain-based systems avoid storing cleartext passwords or sensitive information in one location. Integrating blockchain with crypto wallets, like MetaMask, further strengthens user login by enabling secure, key-based identity checks. This method not only boosts user confidence and privacy but also fits with the future of the decentralized web (Web3). This proposed solution shows how blockchain can transform login systems by providing a secure, scalable, and transparent alternative to traditional login processes.
Cited by 0
Roberto Lublinerman, Christian Szegedy, Stavros Tripakis · 2009
We study modular, automatic code generation from hierarchical block diagrams with synchronous semantics. Such diagrams are the fundamental model behind widespread tools in the embedded software domain, such as Simulink and SCADE. Code is modular in the sense that it is generated for a given composite block independently from context (i.e., without knowing in which diagrams the block is to be used) and using minimal information about the internals of the block. In previous work, we have shown how modular code can be generated by computing a set of interface functions for each block and a set of dependencies between these functions that is exported along with the interface. We have also introduced a quantified notion of modularity in terms of the number of interface functions generated per block, and showed how to minimize this number, which is essential for scalability. Finally, we have exposed
Cited by 0
Chris Winstead, Hui Gao, Student Member · 2008
Abstract — A stochastic iterative decoder implementation is presented for a (16, 11) 2 Block Turbo code. The implementation uses eight-bit precision to represent channel information and a posteriori information. Decisions are made after a fixed interval of 1024 stochastic clocks, resulting in a throughput up to 23Mbps on a Xilinx Virtex II Pro FPGA platform. A novel low-complexity “supernode ” is introduced, resulting in faster convergence with less complexity than previous stochastic decoders. Simulated performance results are presented showing a bit error rate equal to that of sum-product decoding. I.
Cited by 0
Lin Luo · 2012
A considerable drawback of OFDM systems is their high peak-to-average power ratio (PAPR). The Asymmetric-OFDM (A-OFDM) system addresses this problem by reducing the size of fast Fourier transform (FFT) / inverse FFT (IFFT). Based on the layered concept in FFT algorithms and Alamouti-like space time block code (STBC), we extend the A-OFDM to an full diversity MIMO multicarrier system and apply it to vehicle-to-vehicle communications. Comparing with the conventional OFDM with STBC, the proposed system can be arbitrarily adjusted in the number of subchannels (or the length of each subchannel), typically in order to suit requirements for high reliability or low complexity, in different applications and scenarios. Theoretical analysis in a frequency selective channel and simulations in a vehicle-to-vehicle environment show that the proposed system, with any adjustable size of subchannels from 1 to N, N being the transmission block length, has higher reliability than an equivalent MIMO-OFDM system.
Cited by 1
PANG Tianyang, LI Yonggui, NIU Yingtao, XIA Zhi, HAN Chen · SHILAP Revista de lepidopterología · 2019
In order to detect the high-efficiency interference of structural data,the linear block code is taken as the research object,and malicious interference signals are added to the noise model of classical energy detection algorithm to deduce the mathematical expression of test statistics in binary hypothesis model.On this basis,taking the minimum sum of false alarm rate and missed detection rate as the criterion,an energy detection algorithm based on optimal detection threshold is proposed.Simulation results show that the algorithm can detect high-efficiency interference at a low signal-to-interference ratio,and the detection probability is higher than that of the algorithm based on CFAR threshold theory.
Cited by 0Open access
Ali H. Alqahtani, Ahmed Iyanda Sulyman, Abdulhameed Alsanie · International Journal of Antennas and Propagation · 2014
This paper presents a rateless space time block code (RSTBC) for massive MIMO systems. The paper illustrates the basis of rateless space time codes deployments in massive MIMO transmissions over wireless erasure channels. In such channels, data may be lost or is not decodable at the receiver due to a variety of factors such as channel fading, interference, or antenna element failure. We show that RSTBC guarantees the reliability of the system in such cases, even when the data loss rate is 25% or more. In such a highly lossy channel, the conventional fixed-rate codes fail to perform well, particularly when channel state information is not available at the transmitter. Simulation results are provided to demonstrate the BER performance and the spectral efficiency of the proposed scheme.
Cited by 12Open access
Yueqian Li · 2013
We study, analyze, and design communication systems for data transmission over block-fading channels. The block-fading channel is a model for communication under slowly-varying fading; where a codeword spans a few independent fading blocks. Code design strategies for block-fading channels are quite different from those for classical additive white Gaussian noise (AWGN) channels or fully interleaved fading channels.
Cited by 0Open access
Adi Fuchs, Shie Mannor, Uri Weiser et al. · 2014
Memory prefetchers predict streams of memory addresses that are likely to be accessed by recurring invocations of a static instruction. They identify an access pattern and prefetch the data that is expected to be accessed by pending invocations of the said instruction. A stream, or a prefetch context, is thus typically composed of a trigger instruction and an access pattern. Recurring code blocks, such as loop iterations may, however, include multiple memory instructions. Accurate data prefetching for recurring code blocks thus requires tight coordination across multiple prefetch contexts. This paper presents the code block working set (CBWS) prefetcher, which captures the working set of complete loop iterations using a single context. The prefetcher is based on the observation that code block working sets are highly interdependent across tight loop iterations. Using automated annotation of tight loops, the prefetcher tracks and predicts the working sets of complete loop iterations. The proposed CBWS prefetcher is evaluated using a set of benchmarks from the SPEC CPU2006, PARSEC, SPLASH and Parboil suites. Our evaluation shows that the CBWS prefetcher improves the performance of existing prefetchers when dealing with tight loops. For example, we show that the integration of the CBWS prefetcher with the state-of-the-art spatial memory streaming (SMS) prefetcher achieves an average speedup of 1.16× (up to 4× ), compared to the standalone SMS prefetcher.
Cited by 22