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Hadamard transform

About: Hadamard transform is a research topic. Over the lifetime, 7262 publications have been published within this topic receiving 94328 citations.


Papers
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Journal ArticleDOI
TL;DR: In this paper, a hybrid method of Walsh transform denoising and Teager energy operator (TEO) demodulation is proposed to solve the problem of axial piston pump faults.

36 citations

Journal ArticleDOI
TL;DR: In this article, a viscosity-type proximal point algorithm is proposed, comprising of a nonexpansive mapping and a finite sum of resolvent operators associated with monotone bifunctions.
Abstract: The main purpose of this paper is to introduce a viscosity-type proximal point algorithm, comprising of a nonexpansive mapping and a finite sum of resolvent operators associated with monotone bifunctions. A strong convergence of the proposed algorithm to a common solution of a finite family of equilibrium problems and fixed point problem for a nonexpansive mapping is established in a Hadamard space. We further applied our results to solve some optimization problems in Hadamard spaces.

36 citations

Journal ArticleDOI
Zhenyu Liu1, Lingfeng Li1, Yang Song1, Shen Li1, Satoshi Goto1, Takeshi Ikenaga1 
TL;DR: Two fast multiple reference frame ME algorithms are proposed here, following the Hadamard transform coefficient-based all_zeros block early detection algorithm, and two early termination criteria are proposed that ensure the pronounced computation saving efficiency when the encoded video has strong spatial homogeneity or temporal stationarity.
Abstract: In the state-of-the-art video coding standard, H.264/AVC, the encoder is allowed to search for its prediction signals among a large number of reference pictures that have been decoded and stored in the decoder to enhance its coding efficiency. Therefore, the computation complexity of the motion estimation (ME) increases linearly with the number of reference picture. Many fast multiple reference frame ME algorithms have been proposed, whose performance, however, will be considerably degraded in the hardwired encoder design due to the macroblock (MB) pipelining architecture. Considering the limitations of the traditional four-stage MB pipelining architecture, two fast multiple reference frame ME algorithms are proposed here. First, on the basis of mathematical analysis, which reveals that the efficiency of multiple reference frames will be degraded by the relative motion between the camera and the objects, for the slow-moving MB, the authors adopt the multiple reference frames but reduce their search range. On the other hand, for the fast-moving MB, the first previous reference frame is used with the full search range during the ME processing. The mutually exclusive feature between the large search range and the multiple reference frames makes the computation saving performance of the proposed algorithm insensitive to the nature of video sequence. Second, following the Hadamard transform coefficient-based all_zeros block early detection algorithm, two early termination criteria are proposed. These methods ensure the pronounced computation saving efficiency when the encoded video has strong spatial homogeneity or temporal stationarity. Experimental results show that 72.7%-93.7% computation can be saved by the proposed fast algorithms with an average of 0.0899 dB coding quality degradation. Moreover, these fast algorithms can be combined with fast block matching algorithms to further improve their speedup performance.

36 citations

Journal ArticleDOI
TL;DR: A class of functions from Niho exponents with four-valued Walsh transform is obtained for any prime by a uniform method, and the distribution of the Walsh transform values is also completely determined.
Abstract: In this paper, a class of functions from Niho exponents with four-valued Walsh transform is obtained for any prime by a uniform method, and the distribution of the Walsh transform values is also completely determined. In particular, this class of functions is proven to be bent for a special case. Although it is shown that the obtained bent functions are equivalent to the Leander-Kholosha's class of bent functions, a direct and much simpler proof for the bentness of this kind of Niho functions is provided.

36 citations

01 Jan 2010
TL;DR: From the average precision and average recall values obtained by firing 55 queries on the image database it is found that use of row mean and column mean with image fragmentation improves the performance resulting in better image retrieval.
Abstract: Always the thrust for better and faster image retrieval techniques has nourished the research in content based image retrieval. The paper presents 32 novel image retrieval techniques using the feature vectors obtained by applying Walsh transform on row mean and column mean of full image, four fragments, sixteen fragments and 64 fragments of image. All the proposed CBIR techniques are tested on generic image database of size 1000 with 11 image classes. From the average precision and average recall values obtained by firing 55 queries on the image database it is found that use of row mean and column mean with image fragmentation improves the performance resulting in better image retrieval. In all these techniques to speed up the image retrieval process notion of energy compaction is introduced and tested for 100%, 95%, 90% and 85% of energy of feature vectors using Walsh transform.

36 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023339
2022850
2021391
2020444
2019427
2018372