Results 261 to 270 of about 251,049 (300)

Shannon Wavelet Approach to Sub-Band Coding

International Journal of Wavelets, Multiresolution and Information Processing, 2003
It is well known that the Shannon Sampling Theorem allows us to fully recover a continuous-time bandlimited signal from its digital samples, as long as the sampling rate to be chosen is not smaller than the Nyquist frequency. This theory applies to all bandlimited signals, which may or may not occupy the entire frequency band. Hence, it is intuitively
Chui, Charles K., Wang, Jianzhong
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Optimized sub-band coding for MANETs

Proceedings of the International Conference and Workshop on Emerging Trends in Technology, 2010
Real-time voice communication is a critical application for MANETs which are characterized by peer-to-peer network structure, dynamic network topology, limited wireless bandwidth, low-power mobile terminals, high error rates, and the broadcast nature of wireless communications.
A. Rout, S. Sethi
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Hexagonal sub-band coding for images

International Conference on Acoustics, Speech, and Signal Processing, 2003
An image coding system is proposed in which hexagonally sampled images are decomposed into subbands that are selective in both frequency and orientation. Nine high-frequency bands each of one octave and 60 degrees of angular orientation are built on a pyramidal structure along with one low-frequency band.
B. Mahesh, W.A. Pearlman
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Computationally efficient sub-band coding of ECG signals

Medical Engineering & Physics, 1996
A data compression technique is presented for the compression of discrete time electrocardiogram (ECG) signals. The compression system is based on sub-band coding, a technique traditionally used for compressing speech and images. The sub-band coder employs quadrature mirror filter banks (QMF) with up to 32 critically sampled sub-bands.
J H, Husøy, T, Gjerde
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Sub-band coding of images

ICASSP '86. IEEE International Conference on Acoustics, Speech, and Signal Processing, 1986
Subband coding has become quite popular for the source encoding of speech. This paper presents a simple yet efficient extension of this concept to the source coding of images. We specify the constraints for a set of two-dimensional quadrature mirror filters (QMF's) for a particular frequency-domain partition, and show that these constraints are ...
J. Woods, S. O'Neil
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Sub‐band coding of digital images

Journal of the Chinese Institute of Engineers, 1990
Abstract An efficient sub‐band coding method for encoding images is presented in this paper. In this method a frequency band decomposition of the image is carried out by means of two‐dimensional separable quadrature mirror filters (QMF's), which split the image spectrum into sixteen uniform sub‐bands. In the coding process, we employ special quantizers
Jia‐Ching Cheng, Chang‐Fuu Chen
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Comments on “sub-band coding with adaptive bit allocation”

Signal Processing, 1980
C. Galand
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Sub-band coding of monochrome and color images

IEEE Transactions on Circuits and Systems, 1988
An efficient subband coding method for encoding monochrome and color images is presented. In this method, the spectrum of the input image signal is decomposed nonuniformly into seven bands. In the coding process the lowest band is DPCM (differential pulse-code modulation)-coded while the higher bands are PCM-coded.
H. Gharavi, A. Tabatabai
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16kbps Real time QMF sub-band coding implementation

ICASSP '80. IEEE International Conference on Acoustics, Speech, and Signal Processing, 2005
The availability of medium performance microprocessors, in conjunction with different concepts to generate real time efficient signal processing software on microprocessors without hardwired multipliers, allows the real time implementation of sub-band voice compression algorithms.
C. Galand, D. Esteban
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Sub-band coding of images using adaptive VQ and entropy coding

[Proceedings] ICASSP 91: 1991 International Conference on Acoustics, Speech, and Signal Processing, 1991
A study of a subband-based compression algorithm for still pictures is reported. A nonuniform band splitting is performed, then each subband signal is quantized by an adaptive vector quantizer with dynamic bit allocation. The output of each vector quantizer is processed by an arithmetic coder.
G. Furlan, C. Galand, E. Lancon, J. Menez   +3 more
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