Topic
Modified discrete cosine transform
About: Modified discrete cosine transform is a research topic. Over the lifetime, 1453 publications have been published within this topic receiving 30211 citations. The topic is also known as: Modified Discrete Cosine Transform, MDCT.
Papers published on a yearly basis
Papers
More filters
TL;DR: An orthogonal approximation for the 8-point discrete cosine transform (DCT) is introduced, and could outperform state-of-the-art algorithms in low and high image compression scenarios, exhibiting at the same time a comparable computational complexity.
Abstract: An orthogonal approximation for the 8-point discrete cosine transform (DCT) is introduced. The proposed transformation matrix contains only zeros and ones; multiplications and bit-shift operations are absent. Close spectral behavior relative to the DCT was adopted as design criterion. The proposed algorithm is superior to the signed discrete cosine transform. It could also outperform state-of-the-art algorithms in low and high image compression scenarios, exhibiting at the same time a comparable computational complexity.
152 citations
01 Nov 1981
TL;DR: The cosine transform is demonstrated theoretically by showing that it can be derived from the optimum (Karhunen-Loeve) transform in the limiting case when the adjacent data-element correlation tends to unity.
Abstract: The cosine transform is nowadays widely used in image data compression studies as a result of its observed near optimum performance with respect to variance redistribution andits property of reducing block edge effects which occur at extreme values of compression. The reason for its good performance for a widely used class of sources is now demonstrated theoretically by showing that it can be derived from the optimum (Karhunen-Loeve) transform in the limiting case when the adjacent data-element correlation tends to unity.
150 citations
TL;DR: A two-dimensional fast cosine transform algorithm (2-D FCT) is developed for 2m× 2ndata points, an extended version of the 1- D FCT algorithm introduced in a recent paper, but with significantly reduced computations for a 2-D field.
Abstract: A two-dimensional fast cosine transform algorithm (2-D FCT) is developed for 2m× 2ndata points. This algorithm is an extended version of the 1-D FCT algorithm introduced in a recent paper, but with significantly reduced computations for a 2-D field. The rationale for this 2-D FCT is a 2-D decomposition of data sequences into 2- D subblocks with reduced dimension (halves), rather than serial, one-dimensional, separable treatment for the columns and rows of the data sets. Computer simulation for the 2-D FCT algorithms, using a smaller block of data and finite word precision, proves to be excellent in comparison with the direct 2-D discrete cosine transform (2-D DCT). An example of a 4 × 4 2-D inverse fast cosine transform (2-D IFCT) algorithm development is presented in this paper, together with a signal flow graph.
146 citations
TL;DR: The advantages of using the Discrete Cosine Transform (DCT) as compared to the standard Discrete Fourier Transform (DFT) for the purpose of removing noise embedded in a speech signal is illustrated.
146 citations
TL;DR: Generalized Gaussian and Laplacian source models are compared in discrete cosine transform (DCT) image coding and with block classification based on AC energy, the densities of the DCT coefficients are much closer to the LaPLacian or even the Gaussian.
Abstract: Generalized Gaussian and Laplacian source models are compared in discrete cosine transform (DCT) image coding. A difference in peak signal to noise ratio (PSNR) of at most 0.5 dB is observed for encoding different images. We also compare maximum likelihood estimation of the generalized Gaussian density parameters with a simpler method proposed by Mallat (1989). With block classification based on AC energy, the densities of the DCT coefficients are much closer to the Laplacian or even the Gaussian. >
145 citations