In order to reduce the digital stream, the problem of improving the quality of digital filtering based on Discrete Wavelet Transformation (DWT) was analyzed using different options for setting the threshold function and the choice of wavelet basis. Given the considerable interest in this problem and the numerous studies concerning the search for ways to optimize the suppression of interference present in signals and images, the topic continues to be relevant and important. For such tasks as image compression, operations in processing and synthesis of different signals, in the analysis of images of different nature, in reducing (compressing) large amounts of information, and to protect information is often used wavelet transform, implemented on the basis of mirror filters. For the formation of wavelet-transform signals taking into account the threshold functions in the problem of digital stream compression, a standard approach to solving the problem of signal purification from interference and random distortions using Daubechies wavelet and adjusting the signal decomposition coefficients based on wavelet functions using soft and rigid threshold task options. It is shown that the use of complex bases provides an advantage both in terms of threshold filtering error and in terms of reducing the risk of accidental distortion in the reconstruction of the useful signal by wavelet coefficients. Appropriate steps were taken for the test signal and experimental data. When using the threshold function, the large modulus (most significant) wavelet coefficients remain unchanged, and the small ones are reset to zero. The change in the amplitude of the recovered signal leads in the latter case to a decrease in the absolute values of all wavelet coefficients, including large modulo. For those applications where it is important to keep the amplitude characteristics constant, this approach is not suitable, but there are problems where it is more important to maintain the regularity of the signal than to accurately reproduce its amplitude. Rhis is the filtering of images from various obstacles, where the method of "soft" task of the threshold function is a widely used approach. When analyzing signals, the constant amplitude is also not always a mandatory requirement. An audio signal can be amplified after filtering, and pre-cleaning it from interference is more important than changing the amplitude characteristics. The use of complex wavelet transform allowed to obtain error reduction and lower threshold level when adjusting wavelet coefficients, and can be recommended for analysis of complex wavelet transform methods as an effective tool for cleaning signals and images of different nature for further research.
This paper presents the results of measuring the signal-to-noise ratio at the boundary of object contours in highdefinition images after compression of the original digital stream based on the Fourier transform and the discrete cosine transform. It is shown that when choosing the threshold for limiting the spectral components of the image, one should not only focus on the frequency, but also take into account the magnitude of the differences in the brightness signal in areas of low-contrast textures.
The paper deals with video coding based on the use of dependent sources, which is caused by the need to accelerate the coding process. The coding time is directly dependent on the computing power, which with the advent of new standards is not enough. Therefore, the article suggests the results of the study, which are designed to improve existing methods, as well as to continue the progress of scientific research in this area. The results consist of using an approach to compression based on coding methods of dependent sources, which can significantly reduce the complexity of processing on the side of the encoder. The results of the study were obtained using two coding algorithms for fixed and dynamic plots. For comparison, JPEG and, respectively, MPEG encoding standards were defined, as well as an improved algorithm that was considered by the authors in previous papers. It solves the problem of efficiently recovering intermediate frames on the decoder side. When evaluating the movement, search styles have a significant impact on the performance of the algorithm, both the search speed and the quality of the search. The search style should be designed considering the characteristics of the distribution of the motion vector probability (MVP) of the sequences of the real plot. The purpose of this study is to improve the coding efficiency of video sequences using the Diamond Search (DS) algorithm. The results show that DS is efficient and reliable, it can always give a higher search speed in different sequences than other algorithms.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.