scholarly journals Low-Complexity Hierarchical Mode Decision Algorithms Targeting VLSI Architecture Design for the H.264/AVC Video Encoder

VLSI Design ◽  
2012 ◽  
Vol 2012 ◽  
pp. 1-20 ◽  
Author(s):  
Guilherme Corrêa ◽  
Daniel Palomino ◽  
Cláudio Diniz ◽  
Sergio Bampi ◽  
Luciano Agostini
Keyword(s):  
Computational Complexity ◽  
Real Time ◽  
Heuristic Algorithms ◽  
Vlsi Architecture ◽  
Low Complexity ◽  
Multimedia Systems ◽  
Mode Decision ◽  
Compression Performance ◽  
Intraframe Coding ◽  
The Cost

In H.264/AVC, the encoding process can occur according to one of the 13 intraframe coding modes or according to one of the 8 available interframes block sizes, besides the SKIP mode. In the Joint Model reference software, the choice of the best mode is performed through exhaustive executions of the entire encoding process, which significantly increases the encoder's computational complexity and sometimes even forbids its use in real-time applications. Considering this context, this work proposes a set of heuristic algorithms targeting hardware architectures that lead to earlier selection of one encoding mode. The amount of repetitions of the encoding process is reduced by 47 times, at the cost of a relatively small cost in compression performance. When compared to other works, the fast hierarchical mode decision results are expressively more satisfactory in terms of computational complexity reduction, quality, and bit rate. The low-complexity mode decision architecture proposed is thus a very good option for real-time coding of high-resolution videos. The solution is especially interesting for embedded and mobile applications with support to multimedia systems, since it yields good compression rates and image quality with a very high reduction in the encoder complexity.

scholarly journals General Improvements of Heuristic Algorithms for Low Complexity DOA Estimation

2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
Haihua Chen ◽  
Haoran Li ◽  
Mingyang Yang ◽  
Changbo Xiang ◽  
Masakiyo Suzuki
Keyword(s):  
Computational Complexity ◽  
Maximum Likelihood ◽  
Heuristic Algorithms ◽  
Super Resolution ◽  
Doa Estimation ◽  
Low Complexity ◽  
Evolutionary Strategies ◽  
Deterministic Maximum Likelihood ◽  
Dimensional Optimization ◽  
Number Of Particles

Heuristic algorithms are considered to be effective approaches for super-resolution DOA estimations such as Deterministic Maximum Likelihood (DML), Stochastic Maximum Likelihood (SML), and Weighted Subspace Fitting (WSF) which are involved in nonlinear multi-dimensional optimization. Traditional heuristic algorithms usually need a large number of particles and iteration times. As a result, the computational complexity is still a bit high, which prevents the application of these super-resolution techniques in real systems. To reduce the computational complexity of heuristic algorithms for these super-resolution techniques of DOA, this paper proposes three general improvements of heuristic algorithms, i.e., the optimization of the initialization space, the optimization of evolutionary strategies, and the usage of parallel computing techniques. Simulation results show that the computational complexity can be greatly reduced while these improvements are used.

A Fast Scheduling Algorithm for Multiple User MIMO-MRC System

2013 ◽  
Vol 385-386 ◽  
pp. 1738-1742
Author(s):  
Dong Tang ◽  
Ming Xia Lv
Keyword(s):  
Computational Complexity ◽  
Mimo System ◽  
Scheduling Algorithm ◽  
Low Complexity ◽  
Base Station ◽  
User Group ◽  
User Scheduling ◽  
Channel Quality ◽  
Multiple User ◽  
The Cost

When multiple users share the same channel at one time, the total throughput of the communication system can be maximized by allocating the common radio resource to the user or the user group having the best channel quality at a given time and the multiuser diversity gain can be obtained. The object to select the users in the best group is to select the users with the maximum sum capacity. Because of the co-channel interferences among the users, user in the best group is often not the user with the best channel quality when only does it transmit to the base station. As for a scheduling algorithm, exhaustive algorithm is to search the whole possibilities of the user group and is an approach that can get the largest capability of the system by multi-user scheduling. However, this algorithm is quite complex and usually brings huge workload to a base station with multiple antennas, hence the cost of operation to a base station has substantially increased. We propose a fast user selection algorithm with low complexity to reduce the computational complexity of the scheduling algorithm. From the simulation results, this algorithm not only decreases the computational complexity of the scheduling algorithm but also retains large capability of the MIMO system.

scholarly journals Area & Power Efficient VLSI Architecture of Mode Decision in Integer Motion Estimation for HEVC Video Coding Standard

2019 ◽  
Vol 9 (4) ◽  
pp. 2469
Author(s):  
EL Ansari Abdessamad ◽  
Nejmeddine Bahri ◽  
Anass Mansouri ◽  
Nouri Masmoud ◽  
Ahaitouf Ali
Keyword(s):  
Motion Estimation ◽  
Real Time ◽  
Vlsi Architecture ◽  
Hardware Architecture ◽  
Video Encoding ◽  
Mode Decision ◽  
Decision Algorithm ◽  
Real Time Processing ◽  
Time Processing ◽  
Block Sizes

<span lang="EN-US">In this paper, we propose a new parallel hardware architecture for the mode decision algorithm, that it is based on the Sum Absolute of the Difference (SAD) for compute the motion estimation, which is the most critical algorithm in the recent video encoding standard HEVC. In fact, this standard introduced new large variable block sizes for the motion estimation algorithm and therefore the SAD requires a more reduced execution time in order to achieve the real time processing even for the ultra-high resolution sequences. The proposed accelerator executes the SAD algorithm in a parallel way for all sub-block prediction units (PUs) and coding unit (CU) whatever their sizes, which turns in a huge improvements in the performances, given that all the block sizes, PUs in each CU, are supported and processed in the same time. The Xilinx Artix-7 (Zynq-7000) FPGA is used for the prototyping and the synthesis of the proposed accelerator. The mode decision for motion estimation scheme is implemented with 32K LUTs, 50K registers and 108Kb BRAMs. The implementation results show that our hardware architecture can achieve 30 frames per second of the 4K (3840 × 2160) resolutions in real time processing at 115.15MHz.</span>

Spatial Interpolators for Intra-Frame Resampling of SAR Videos: A Comparative Study Using Real-Time HD, Medical and Radar Data

2020 ◽  
Vol 15 (2) ◽  
pp. 144-196 ◽  
Author(s):  
Mohammad R. Khosravi ◽  
Sadegh Samadi ◽  
Reza Mohseni
Keyword(s):  
Computational Complexity ◽  
Real Time ◽  
Video Compression ◽  
Nearest Neighbor ◽  
Radar Data ◽  
Edge Preservation ◽  
Edge Information ◽  
Video Codecs ◽  
Comparative Results ◽  
Interesting Area

Background: Real-time video coding is a very interesting area of research with extensive applications into remote sensing and medical imaging. Many research works and multimedia standards for this purpose have been developed. Some processing ideas in the area are focused on second-step (additional) compression of videos coded by existing standards like MPEG 4.14. Materials and Methods: In this article, an evaluation of some techniques with different complexity orders for video compression problem is performed. All compared techniques are based on interpolation algorithms in spatial domain. In details, the acquired data is according to four different interpolators in terms of computational complexity including fixed weights quartered interpolation (FWQI) technique, Nearest Neighbor (NN), Bi-Linear (BL) and Cubic Cnvolution (CC) interpolators. They are used for the compression of some HD color videos in real-time applications, real frames of video synthetic aperture radar (video SAR or ViSAR) and a high resolution medical sample. Results: Comparative results are also described for three different metrics including two reference- based Quality Assessment (QA) measures and an edge preservation factor to achieve a general perception of various dimensions of the mentioned problem. Conclusion: Comparisons show that there is a decidable trade-off among video codecs in terms of more similarity to a reference, preserving high frequency edge information and having low computational complexity.

scholarly journals Fast 10-Point DFT Algorithm for Power System Harmonic Analysis

2021 ◽  
Vol 11 (15) ◽  
pp. 7007
Author(s):  
Janusz P. Paplinski ◽  
Aleksandr Cariow
Keyword(s):  
Computational Complexity ◽  
Power System ◽  
Harmonic Analysis ◽  
Efficient Algorithm ◽  
System Analysis ◽  
Spectral Leakage ◽  
Power System Analysis ◽  
Improve Accuracy ◽  
The Cost ◽  
Harmonic Power

This article presents an efficient algorithm for computing a 10-point DFT. The proposed algorithm reduces the number of multiplications at the cost of a slight increase in the number of additions in comparison with the known algorithms. Using a 10-point DFT for harmonic power system analysis can improve accuracy and reduce errors caused by spectral leakage. This paper compares the computational complexity for an L×10M-point DFT with a 2M-point DFT.

A Determinant Elimination Method for Bottleneck Assignment and Generalized Assignment Problems

2012 ◽  
Vol 239-240 ◽  
pp. 1522-1527
Author(s):  
Wen Bo Wu ◽  
Yu Fu Jia ◽  
Hong Xing Sun
Keyword(s):  
Computational Complexity ◽  
Optimization Algorithm ◽  
Assignment Problem ◽  
Numerical Experiments ◽  
High Efficiency ◽  
Synthesis Method ◽  
Assignment Problems ◽  
Generalized Assignment ◽  
The Cost ◽  
Time And Space Complexity

The bottleneck assignment (BA) and the generalized assignment (GA) problems and their exact solutions are explored in this paper. Firstly, a determinant elimination (DE) method is proposed based on the discussion of the time and space complexity of the enumeration method for both BA and GA problems. The optimization algorithm to the pre-assignment problem is then discussed and the adjusting and transformation to the cost matrix is adopted to reduce the computational complexity of the DE method. Finally, a synthesis method for both BA and GA problems is presented. The numerical experiments are carried out and the results indicate that the proposed method is feasible and of high efficiency.

scholarly journals Evaluation of StrepBSelectChromogenic Medium and the Fast-Track Diagnostics Group B Streptococcus (GBS) Real-Time PCR Assay Compared to Routine Culture for Detection of GBS during Antepartum Screening

2017 ◽  
Vol 55 (7) ◽  
pp. 2137-2142 ◽  
Author(s):  
Deirdre L. Church ◽  
Heather Baxter ◽  
Tracie Lloyd ◽  
Oscar Larios ◽  
Daniel B. Gregson
Keyword(s):  
Real Time ◽  
Real Time Pcr ◽  
Fast Track ◽  
Group B Streptococcus ◽  
Culture Method ◽  
Predictive Values ◽  
Content Type ◽  
Standard Culture ◽  
Group B ◽  
The Cost

ABSTRACTLife-threatening infection in neonates due to group BStreptococcus(GBS) is preventable by screening of near-term pregnant women and treatment at delivery. A total of 295 vaginal-rectal swabs were collected from women attending antepartum clinics in Calgary, Alberta, Canada. GBS colonization was detected by the standard culture method (Strep B Carrot Broth subcultured to blood agar with a neomycin disk) and compared to recovery with Strep Group B Broth (Dalynn Biologicals) subcultured to StrepBSelectchromogenic medium (CM; Bio-Rad Laboratories) and the Fast-Track Diagnostics GBS real-time PCR (quantitative PCR [qPCR]) assay (Phoenix Airmid Biomedical Corp.) performed with broth-enriched samples and the Abbottm2000sp/m2000rt system. A total of 62/295 (21%) women were colonized with GBS; 58 (19.7%) cases were detected by standard culture, while CM and qPCR each found 61 (20.7%) cases. The qPCR and CM were similar in performance, with sensitivities, specificities, and positive and negative predictive values of 98.4 and 98.4%, 99.6 and 99.6%, 98.4 and 98.4%, and 99.6 and 99.6%, respectively, compared to routine culture. Both qPCR and CM would allow more rapid reporting of routine GBS screening results than standard culture. Although the cost per test was similar for standard culture and CM, the routine use of qPCR would cost approximately four times as much as culture-based detection. Laboratories worldwide should consider implementing one of the newer methods for primary GBS testing, depending on the cost limitations of different health care jurisdictions.

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