Article
Computer Science, Information Systems
Gihwan Lee, Yoonsik Choe
Summary: Image transforms are essential for compression. This study presents a framework based on two-dimensional discrete cosine transform (DCT) to enhance data compaction abilities efficiently by utilizing DCT properties and approximating its direction. The proposed framework outperforms other methods in terms of computational speed without sacrificing performance.
Article
Engineering, Electrical & Electronic
Diego F. G. Coelho, Renato J. Cintra, Arjuna Madanayake, Sirani M. Perera
Summary: This paper introduces a collection of scaling methods for generating 2N-point DCT-II approximations based on N-point low-complexity transformations. The proposed techniques outperform the transforms resulting from the JAM scaling method in terms of total error energy and mean squared error, as demonstrated by extensive error analysis based on statistical simulation. Additionally, a hardware implementation shows the competitiveness of the proposed methods compared to the JAM scaling method.
IEEE TRANSACTIONS ON SIGNAL PROCESSING
(2021)
Article
Chemistry, Analytical
Loris Nanni, Giovanni Minchio, Sheryl Brahnam, Davide Sarraggiotto, Alessandra Lumini
Summary: This paper examines strategies for enhancing the performance of ensembles of Siamese networks for image classification, utilizing different loss functions and methods for building dissimilarity spaces. Results demonstrate the robustness and versatility of the approach across various data sets, showing improved performance compared to standalone CNNs when combined in an ensemble.
Article
Computer Science, Artificial Intelligence
Rachna Mehta, Karan Kumar, Adi Alhudhaif, Fayadh Alenezi, Kemal Polat
Summary: This paper introduces a novel image resampling forgery detection technique that recognizes resampling operations by extracting Markov features in the spatial and Discrete Cosine Transform domains. The proposed algorithm achieves high classification accuracy through the use of multiple classifiers and weighted majority voting. It can also detect the type of interpolation kernel, forgery size, and resampling type, and includes a Graphical User Interface for forgery detection.
APPLIED SOFT COMPUTING
(2023)
Article
Plant Sciences
Hong Lin, Rita Tse, Su-Kit Tang, Zhenping Qiang, Giovanni Pau
Summary: Bringing frequency representation into Few-shot learning paradigm for plant disease recognition shows rich patterns for image understanding, with significant performance improvements demonstrated through the design of discrete cosine transform module, learning-based frequency selection method, and Gaussian-like calibration module.
Article
Mathematics
Vitaly Kober
Summary: This paper introduces the applications of discrete cosine and sine transforms in first-order Markov stationary signals and proposes fast algorithms based on a generalized solution and pruned discrete sine transforms. The performances of the algorithms are compared with other algorithms, demonstrating low complexity and fast execution time.
Article
Computer Science, Artificial Intelligence
Lusia Rakhmawati, Wirawan Wirawan, Suwadi Suwadi, Claude Delpha, Pierre Duhamel
Summary: The paper proposes a novel reversible robust watermarking scheme based on the JPEG image, which minimizes total distortion for the watermarked image by adaptively selecting embedding strengths and coefficients and using an advanced block selection strategy to correspond to the distortion. Experimental results show that the method can maintain good visual quality while being robust to geometrical and image processing attacks.
EXPERT SYSTEMS WITH APPLICATIONS
(2022)
Article
Energy & Fuels
Hyunmin Kim, Tsubasa Onishi, Hongquan Chen, Akhil Datta-Gupta
Summary: Embedded Discrete Fracture Model (EDFM) is a promising approach to describe reservoirs with fractures, and a novel parameterization and hierarchical multi-scale history matching formulation has been proposed to address the limitations of conventional inversion methods.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2021)
Article
Mathematics, Applied
Mateusz Krukowski
Summary: This paper provides a detailed explanation on how the (continuous) cosine transform and the discrete(-time) co-sine transform naturally arise as manifestations of the celebrated Gelfand transform. The introduction of the cosine convolution *(c) plays a key role in establishing the bijection between Delta(L-1(G), *(c)) and the cosine class COS( G), and in reducing the Gelfand transform to the cosine transforms.
RESULTS IN MATHEMATICS
(2022)
Article
Engineering, Electrical & Electronic
Yu Liu, Feng Zhang, Hongxia Miao, Ran Tao
Summary: This paper introduces the sliding window algorithm for real-time calculation of fractional Fourier transform, proposing the hopping DFrFT algorithm and methods applied in DTFrFT and DFrCT/DFrST/DFrHT. Simulation results confirm that the sliding algorithm can reduce computation complexity without degrading precision.
Article
Computer Science, Interdisciplinary Applications
Thiago M. D. Silva, Renan Vieira Bela, Sinesio Pesco, Abelardo Barreto
Summary: This study attempts to utilize the ES-MDA method to determine individual layer skin zone properties and finds that in all tested cases, the resulting histogram contains reference parameters. Through a sensitivity study on the performance of ES-MDA with different assimilations and ensemble sizes, the advantages of this method in evaluating model parameters are discovered.
COMPUTERS & GEOSCIENCES
(2021)
Article
Engineering, Electrical & Electronic
Carlos Javier Morales-Perez, Jose de Jesus Rangel-Magdaleno, Hayde Peregrina-Barreto, Arturo Garcia-Perez, Juan Manuel Ramirez-Cortes
Summary: This article proposes a noise reduction methodology based on the orthogonal matching pursuit algorithm with dictionaries constructed from kernel functions of the discrete cosine transform and discrete sine transform. The methodology is proven to be effective in reducing noise and recovering signals through testing on synthetic and real electrical signals.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2022)
Article
Engineering, Electrical & Electronic
I Mamatha, Shikha Tripathi, T. S. B. Sudarshan
Summary: This paper proposes a hybrid architecture that supports multiple discrete transforms, enabling both parallel and sequential computations. By considering the computational needs across transforms and using mode control, the architecture allows for the selection of appropriate transforms for different applications, supporting multiple 8-point discrete transforms. The proposed approach is useful in heterogeneous systems requiring output from multiple transforms in either parallel or sequential mode.
CIRCUITS SYSTEMS AND SIGNAL PROCESSING
(2022)
Article
Computer Science, Information Systems
Srilekha Paul, Arup Kumar Pal
Summary: This paper proposes a passive forensic scheme for copy-move forgery detection in digital images that reduces the search space by using a Gaussian image pyramid to generate and analyze input images at different resolutions. The proposed approach initially performs relative forgery detection through block-wise processing of lower resolution components of the original image, and then actual forgery detection is performed on the reduced search space. The procedure is computationally efficient and robust against various attacks and post-processing operations.
MULTIMEDIA TOOLS AND APPLICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Chun-Chieh Lin, Pei-Chann Chang, Ping-Heng Tsai
Summary: This study proposes a dual-adaptive approach based on DCT for the removal of baseline wander in ECG records. The method accurately calculates the cardiac fundamental frequency and uses DCT coefficients to distinguish between baseline wander and ECG. A new filtering technique based on DCT is then applied to suppress baseline wander. Experimental results demonstrate significant improvements in performance when using this dual-adaptive approach.
APPLIED SCIENCES-BASEL
(2022)