scholarly journals Extended Multi WLS Method for Lossless Image Coding

Entropy ◽  
2020 ◽  
Vol 22 (9) ◽  
pp. 919
Author(s):  
Grzegorz Ulacha ◽  
Ryszard Stasiński ◽  
Cezary Wernik
Keyword(s):  
Image Coding ◽  
Constant Component ◽  
Point Of View ◽  
Least Square ◽  
Main Stage ◽  
Current Image ◽  
Coding Method ◽  
Data Compaction ◽  
Lossless Coding ◽  
Arithmetic Coder

In this paper, the most efficient (from data compaction point of view) and current image lossless coding method is presented. Being computationally complex, the algorithm is still more time efficient than its main competitors. The presented cascaded method is based on the Weighted Least Square (WLS) technique, with many improvements introduced, e.g., its main stage is followed by a two-step NLMS predictor ended with Context-Dependent Constant Component Removing. The prediction error is coded by a highly efficient binary context arithmetic coder. The performance of the new algorithm is compared to that of other coders for a set of widely used benchmark images.

scholarly journals A High Efficiency Multistage Coder for Lossless Audio Compression using OLS+ and CDCCR method

2019 ◽  
Vol 9 (23) ◽  
pp. 5218 ◽  
Author(s):  
Ulacha ◽  
Wernik
Keyword(s):  
High Efficiency ◽  
Prediction Method ◽  
Constant Component ◽  
Least Square ◽  
Classification Model ◽  
Audio Compression ◽  
Ordinary Least Square ◽  
Arithmetic Coder ◽  
Different Levels

In this paper, the improvement of the cascaded prediction method was presented. Three types of main predictor block with different levels of complexity were compared, including two complex prediction methods with backward adaptation, i.e., extension Active Level Classification Model (ALCM+) and extended Ordinary Least Square (OLS+). Our own approach to implementation of the effective context-dependent constant component removal block is also presented. Additionally, the improved adaptive arithmetic coder with short, medium and long-term adaptation was presented, and the experiment was carried out comparing the results with other known lossless audio coders against which our method obtained the best efficiency.

scholarly journals Adaptive technique for smoothing telemetric measurements with the use of fuzzy inference

2016 ◽  
pp. 88-96
Author(s):  
N. A. Pervushina ◽  
D. E. Donovskiy
Keyword(s):  
Fuzzy Inference ◽  
Piecewise Linear ◽  
Least Square Method ◽  
Point Of View ◽  
Least Square ◽  
Piecewise Linear Approximation ◽  
Adaptation Mechanism ◽  
Inference System ◽  
Window Width ◽  
Data Location

The study focuses on the technique that allows smoothing the results of telemetric measurements by sliding piecewise-linear approximation. We calculated the model coefficients at smoothing, as well as coefficient dispersion, using the least square method (LSM). Moreover, we developed the algorithm for adapting the sliding window width depending on nature of the initial data location. We implemented the adaptation mechanism by means of a fuzzy logic inference system, which is of particular interest from the point of view of novelty of the approach and practical application in processing the results of telemetric measurements.

Sponsor ownership and IPO initial return: evidence from Pakistan stock exchange

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Waqas Mehmood ◽  
Rasidah Mohd-Rashid ◽  
Abd Halim Ahmad ◽  
Saqib Amin
Keyword(s):  
Initial Public Offering ◽  
Positive Impact ◽  
Stock Exchange ◽  
Point Of View ◽  
Least Square ◽  
Content Type ◽  
Interaction Variable ◽  
Regulatory Changes ◽  
Initial Return ◽  
Regulation Changes

Purpose The purpose of this paper was to examine whether or not the sponsor lock-up ratio, lock-up period, regulation changes and interaction variable (oversubscription [OSR]) affected initial public offering (IPO) initial return. Design/methodology/approach A complete sample of 111 listed IPOs in Pakistan stock exchange from 1996 to 2018 was incorporated. Based on the cross-section data, this paper estimated using ordinary least square and quantile least square for robustness. In addition to that, this paper estimated the data using stepwise least square to inspect the signalling aspect of the lock-up ratio, lock-up period and regulation changes on IPO initial return. Findings This study showed that the lock-up ratio, lock-up period and regulatory changes had a positive impact on the IPO’s initial return. Furthermore, the assertion of interaction variable (regulation changes × OSR) and (lock-up period × OSR) was a negatively significant factor in influencing the IPO’s initial return. The results of this paper were robust to endogeneity bias. Practical implications The finding of this study proposed that sponsors of IPOs can be a strong signal of risk or quality, which was consistent with the signalling theory prediction. Concurrently, investors must be aware of the total proportions of lock-up ratio so that they can estimate the chances of getting the highest initial return on IPOs. From the regulators’ point of view, it is suggested that the lock-up ratio and the lock-up period should be determined with a deeper understanding and incorporated into the equity guidelines as it is evident that these factors are priced by the market. Originality/value Studies on the effect of sponsors have always been centred on well-recognized firms. Therefore, using the IPO samples listed in Pakistan, this paper contributes to the IPO literature by investigating the lock-up ratio of the sponsor, the lock-up period and the regulatory changes to the initial IPO return. Additionally, OSR has been introduced as an interaction variable among the sponsors’ lock-up period and regulations changes to explain the ongoing IPO initial return phenomenon.

AN IMPROVED EMBEDDED ZEROTREE WAVELET IMAGE CODING METHOD BASED ON COEFFICIENT PARTITIONING USING MORPHOLOGICAL OPERATION

2000 ◽  
Vol 14 (06) ◽  
pp. 795-807 ◽  
Author(s):  
JUNMEI ZHONG ◽  
C. H. LEUNG ◽  
Y. Y. TANG
Keyword(s):  
Image Compression ◽  
Video Coding ◽  
Image Coding ◽  
Experimental Results ◽  
Morphological Operation ◽  
Compression Algorithms ◽  
Still Image ◽  
Coding Method ◽  
Wavelet Image ◽  
Image Compression Algorithm

In recent years, wavelets have attracted great attention in both still image compression and video coding, and several novel wavelet-based image compression algorithms have been developed so far, one of which is Shapiro's embedded zerotree wavelet (EZW) image compression algorithm. However, there are still some deficiencies in this algorithm. In this paper, after the analysis of the deficiency in EZW, a new algorithm based on quantized coefficient partitioning using morphological operation is proposed. Instead of encoding the coefficients in each subband line-by-line, regions in which most of the quantized coefficients are significant are extracted by morphological dilation and encoded first. This is followed by using zerotrees to encode the remaining space which has mostly zeros. Experimental results show that the proposed algorithm is not only superior to the EZW, but also compares favorably with the most efficient wavelet-based image compression algorithms reported so far.

Research on Lossless Predictive Coding Methods for Stereo Images

2014 ◽  
Vol 596 ◽  
pp. 406-412 ◽  
Author(s):  
Shi Gao Li
Keyword(s):  
Image Coding ◽  
Predictive Coding ◽  
Prediction Method ◽  
Code Rate ◽  
Experimental Results ◽  
Stereo Image ◽  
Stereoscopic Image ◽  
Coding Method ◽  
Image Pairs ◽  
Very High

There exists very high correlation between left-view images and right-view images of stereo image pairs. The correlation can help to reduce the stereoscopic image coding bit rate. Proposed methods first estimate the disparity by using causal neighborhood pixels. And then a prediction method which combines inter-view prediction with intra-view prediction is used to obtain a better predictive coding method for target-view images. The reference-view images are then encoded by using those commonly used prediction coding method. The experimental results show that compared with those methods using only intra-view correlation, the proposed method can obtain lower code rate.

Lossless coding method for black-ink signals of high-quality printing images

1998 ◽  
Author(s):  
Shigeo Kato ◽  
Muling Guo ◽  
Madoka Hasegawa
Keyword(s):  
High Quality ◽  
Coding Method ◽  
Lossless Coding
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