This paper describes a source controlled variable bit-rate (SCVBR) speech coder based on the concept of prototype waveform interpolation. The coder uses a four mode classification : silence, voiced, unvoiced and transition. These modes are detected after the speech has been decomposed into slowly evolving (SEW) and rapidly evolving (REW) waveforms. A voicing activity detection (VAD), the relati...

Natural images often consist of many distinct regions with individual characteristics. Adaptive image coders exploit this feature of natural images to obtain better compression results. In this paper, we propose a classi cationbased scheme for both adaptive prediction and entropy coding in a lossless image coder. In the proposed coder, blocks of image samples (in PCM domain) are classi ed to se...

A subband lter bank is applied to decompose seismic stack sections. The lter bank is designed to give almost perfect reconstruction and maximum coding gain. A variable bit rate coding scheme is used on the sub-band signals. Blocks of subband samples are dynamically classiied into diierent classes according to the blockwise root mean-square value. Each subband sample is then quantized in a unifo...

The Minimum-Entropy Clustering (MEC) algorithm proposed in this paper provides an optimal method for addressing the non-stationarity of a source with respect to entropy coding. This algorithm clusters a set of vectors (where each vector consists of a xed number of contiguous samples from a discrete source) using a minimum entropy criterion. In a manner similar to Classi ed Vector Quantization (...

The VQ-style clustering algorithm proposed in this paper provides an optimal method for addressing the non-stationarity of a source with respect to entropy coding. This algorithm which is named Minimum-Entropy Clustering (MEC), clusters a set of vectors (where each vector consists of a fixed number of contiguous samples from a discrete source) using a minimum entropy criterion. In a manner simi...

A mixture distribution model is introduced to characterize the source statistics in a frequency domain image coder. More speciically, a Gaussian mixture distribution is shown to be a good statistical model of the probability density function of the composite decomposed signal. Theoretical results based on the mixture distribution model are found that quantify the obtainable entropy rate gain in...

We extend the work of Sherwood and Zeger [1, 2] to progressive video coding for noisy channels. By utilizing a three-dimensional (3-D) extension of the set partitioning in hierarchical trees (SPIHT) algorithm [3], we cascade the resulting 3-D SPIHT video coder [4, 5] with the ratecompatible punctured convolutional (RCPC) channel coder [6] for transmission of video over a binary symmetric channe...

We extend our previous work on space-frequency quantization (SFQ) for image coding from wavelet transforms to the more general wavelet packet transforms. The resulting wavelet packet coder offers a universal transform coding framework within the constraints of filterbank structures by allowing joint transform and quantizer design without assuming a priori statistics of the input image. In other...

In this paper, a high-quality wideband speech coder is proposed. The coding structure resembles a LD-CELP coder, however, several novel improvements are made. The gain adapter for the stochastic codebook is driven by a neural network and it updates the excitation gain in a sample-by-sample fashion. The purpose of incorporating a neural network is to exploit both the intraand inter-frame correla...