In this paper we describe a trellis representation of variable length coded data which is capable of being used for bit-level or symbol-level maximum a posteriori (MAP) decoding of variable length codes (VLC). A bit-level soft-input/soft-output module is derived and is applied in an iterative decoding structure consisting of an outer variable length code and an inner convolutional code. Due to ...

Optimal vector quantization of variable-dimension vectors in principle is feasible by using a set of fixed dimension VQ codebooks. However, for typical applications, such a multi-codebook approach demands a grossly excessive and impractical storage and computational complexity. Efficient quantization of such variable-dimension spectral shape vectors is the most challenging and difficult encodin...

We propose a new direct-sequence code division multiple access (CDMA) strategy for combining voice and variable-rate data. Our admission control policy uses a reservation policy for voice calls and different variable-rate schemes for data to maximize throughput on the residual bandwidth unused by voice. The data schemes we consider include variable bit rate (VBR), multicode (MC), and variable c...

H.263+ is an emerging video compression standard for the low bit rate visual communication. Up to now, most H.263+ rate control algorithms, especially that in the test model of the near-term (TMN), focus on macroblock level bit allocation and low latency under a constant-frame-rate and constant-bit-rate (CBR) channel. As expected, these algorithms are not capable of handling the transmission ba...

This letter presents a real-time lossless compression/decompression unit for disparity map information used in 3D teleconferencing systems. A lossless compression algorithm is used to compress the disparity map data in real-time, resulting in a variable bit-rate data stream that has to be transmitted through a constant bit-rate channel. The system uses a controlled-data-loss method for data rat...

One of the top tasks for video streaming, video surveillance, video conferencing and video broadcasting is a low bit rate and real-time video coding. The most popular low bit rate video compression approach is based on the H.264/AVC standard [1]. This standard provides high compression efficiency due to hybrid video coding which includes intra-frame prediction, variable-size block motion estima...

Today, public network providers perform usage-based charging of ATM services based on transmitted cells, allocated bandwidth, and connection time. Nevertheless, it is important being able to simplify the process of charging by considering the requested service category and the implied Quality of Service (QoS) that might be negotiated additionally. We present a charging framework and its applica...

The video content for on-demand services is generally stored and streamed in a compressed format. The compressed video is naturally with the VBR (variable-bit-rate) property and the stream traffic is highly burst. Subject to the QoS-guaranteed playback, the WAN bandwidth needs to allocate the video's peak bit rate if there is no client buffer for regulating the video delivery [7][8][9][10][11]....

A new dynamic reservation integrated services multiple access (DRISMA) protocol is proposed for the emerging wireless ATM networks. Compared to other PRMA-based protocols, DRISMA has two distinctive features. First, while each voice station reserves isochronous channels by capturing minislots, both the capturing probability and the number of mini-slots per frame are adjusted dynamically to enha...

We address the problem of determining the minimum bit-rate needed to stabilize a linear time-invariant process. For the noise free case, we determine a bit-rate below which stabilization is not possible and above which asymptotic stabilization can be achieved. Inspired by differential pulse code modulation (DPCM) techniques, we propose practical encoding/decoding schemes that guarantee boundedn...