Historically, the discovery of new code families and decoding algorithms has been followed by fundamental limits on their required complexity. To arrive at such limits, it is necessary to have general models that capture the essence of the approach to decoding, while still allowing for the possibility of as yet undiscovered families of codes. By adapting sphere-packing arguments used earlier in...

Current state-of-the-art statistical machine translation (SMT) relies on simple feature functionswhichmake independence assumptions at the level of phrases or hierarchical rules. However, it is well-known that discriminative models can benefit from rich features extracted from the source sentence context outside of the applied phrase or hierarchical rule, which is available at decoding time. We...

A modi ed decoding algorithm for automatic speech recognition (ASR) will be described which facilitates a closer coupling between the acoustic and language modeling components of a speech recognition system. This closer coupling is obtained by extracting word level measures of acoustic con dence during decoding, and making coded representations of these con dence measures available to the ASR n...

The Hidden Dynamic Model (HDM) has been an attractive acoustic modeling approach because it provides a computational model for coarticulation and the dynamics of human speech. However, the lack of a direct decoding algorithm has been a barrier to research progress on HDM. We have developed a new HDM-based acoustic model, the Hidden-Trajectory HMM (HTHMM), which combines the state/mixture topolo...

In this paper we address the problem of decoding 2D convolutional codes over the erasure channel. In particular, we present a procedure to recover bursts of erasures that are distributed in a diagonal line. To this end we introduce the notion of balls around a burst of erasures which can be considered an analogue of the notion of sliding window in the context of 1D convolutional codes. The main...

Several recent publications have shown that joint sourcechannel decoding (JSCD) could be a powerful technique for taking advantage of residual source redundancy. Furthermore, it appeared that the principle could also be successfully applied to variable length codes (VLCs). This paper gives an in-depth analysis of a new method recently proposed in [1], [2] to provide a low complexity soft decodi...

Context Adaptive Variable Length Decoding (CAVLD) module takes the lion chair of the H.264/AVC video decoder time due to its complexity. In order to ameliorate decoding speed, a new CAVLD algorithm and an efficient internal memory design were implemented on Digital Signal Processor (DSP). The proposed CAVLD algorithm, Zero Length Prefix (ZLP), was designed to optimize the first syntax element: ...

In this paper we address the problem of decoding 2D convolutional codes over the erasure channel. To this end we introduce the notion of balls around a burst of erasures which can be considered an analogue of the notion of sliding window in the context of 1D convolutional codes. The main idea is to reduce the decoding problem of 2D convolutional codes to a problem of decoding a set of associate...

A m a x i m u m likelihood decoding algo-r i t h m is presented for tailbiting trellises for block codes. The algorithm works in t w o phases. The first phase is a V i t e r b i decoding algorithm on the tailbiting trellis, while the second uses the A* algorithm adapted for application in this context. Results of simulations on tailbiting trellises for some block codes, indicate that t h i s de...

This paper presents a fast context-based adaptive variable-length decoding (CAVLD) method of H.264/AVC with a very long instruction word-based bitstream processing unit (BsPU) designed for entropy decoding of multiple video formats. A new table mapping algorithm for the coeff_token, level, and run_before syntax elements of the quantized transform coefficients is proposed, and many branch operat...