Results 161 to 170 of about 10,977 (213)

The Discrete Cosine Transform (DCT)

2009
The Fourier transform and the DFT are designed for processing complex-valued signals, and they always produce a complex-valued spectrum even in the case where the original signal was strictly realvalued. The reason is that neither the real nor the imaginary part of the Fourier spectrum alone is sufficient to represent (i.e., reconstruct) the signal ...
Wilhelm Burger, Mark J. Burge
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Reversible discrete cosine transform

Proceedings of the 1998 IEEE International Conference on Acoustics, Speech and Signal Processing, ICASSP '98 (Cat. No.98CH36181), 2002
In this paper a reversible discrete cosine transform (RDCT) is presented. The N-point reversible transform is firstly presented, then the 8-point RDCT is obtained by substituting the 2 and 4-point reversible transforms for the 2 and 4-point transforms which compose the 8-point discrete cosine transform (DCT), respectively.
K. Komatsu, K. Sezaki
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Fast Three-Dimensional Discrete Cosine Transform

SIAM Journal on Scientific Computing, 2008
Summary: A fast three-dimensional discrete cosine transform algorithm (3D FCT) and a fast 3D inverse cosine transform (3D IFCT) algorithm are presented, suitable for analysis of 3D data points. Many existing algorithms for three-dimensional data points make use of either the 1D cosine transform or both the 2D and 1D cosine transforms.
Lee, M. C., Chan, Raymond K. W., Adjeroh, Don A.   +2 more
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On Computing the Discrete Cosine Transform

IEEE Transactions on Computers, 1978
Haralick has shown that the discrete cosine transform of N points can be computed more rapidly by taking two N-point fast Fourier transforms (FFT's) than by taking one 2N-point FFT as Ahmed had proposed. In this correspondence, we show that if Haralick had made use of the fact that the FFT's of real sequences can be computed more rapidly than general ...
Tseng, B. D., Miller, W. C.
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Algorithm 749: fast discrete cosine transform

ACM Transactions on Mathematical Software, 1995
An in-place algorithm for the fast, direct computation of the forward and inverse discrete cosine transform is presented and evaluated. The transform length may be an arbitrary power of two.
Sherlock, B. G., Monro, D. M.
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Discrete cosine transform of encrypted images

2008 15th IEEE International Conference on Image Processing, 2008
Processing a signal directly in the encrypted domain provides an elegant solution in application scenarios where valuable signals must be protected from a malicious processing device. In a previous paper we considered the implementation of the ID discrete fourier transform (DFT) in the encrypted domain, by using the homomorphic properties of the ...
T. Bianchi, PIVA, ALESSANDRO, M. Barni
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Efficient Recursive Algorithm for Discrete Cosine Transform and Inverse Discrete Cosine Transform

2018 International Conference on Sustainable Energy, Electronics, and Computing Systems (SEEMS), 2018
In this paper, efficient algorithms based on recursive technique are proposed for even length Discrete cosine Transform (DCT) and Inverse Discrete Cosine Transform (IDCT). The recursive relations are derived to compute N-point DCT and IDCT coefficients by utilizing $\frac {N}{1}$execution cycles per transform coefficient.
Pragati Dahiya, Priyanka Jain
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Binary Discrete Cosine and Hartley Transforms

IEEE Transactions on Circuits and Systems I: Regular Papers, 2013
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Bouguezel, Saad, Ahmad, M. Omair, Swamy, M. N. S.   +2 more
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2D lossless discrete cosine transform

Proceedings 2001 International Conference on Image Processing (Cat. No.01CH37205), 2002
Since the lossless DCT is compatible with JPEG or MPEG, it is expected to play an important role in unified lossless/lossy image coding. However, there is a problem that the difference between the transform coefficients of the lossless DCT and those of the (lossy) DCT is not very small. We present the design of a two dimensional lossless DCT based on a
K. Komatsu, K. Sezaki
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The fractional discrete cosine transform

IEEE Transactions on Signal Processing, 2002
The extension of the Fourier transform operator to a fractional power has received much attention in signal theory and is finding attractive applications. The paper introduces and develops the fractional discrete cosine transform (DCT) on the same lines, discussing multiplicity and computational aspects. Similarities and differences with respect to the
CARIOLARO, GIANFRANCO, ERSEGHE, TOMASO, KRANIAUSKAS P.   +2 more
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