A robust video coding scheme using multiple description coding (MDC) is presented. MDC is an effective approach to combat packet losses in the Internet and wireless networks. The new coder is built on the top of the video coding standard H. 263 baseline coder and employs multiple description vector quantization using translated lattices with local optimization (MDVQ-TLLO). MDVQ-TLLO introduces ...

This paper describes the 6.4 kbit/s CS-ACELP coder being standardized as annex D to ITU-T G.729. The coder is based on the same building blocks as the 8 kbit/s G.729 to facilitate low complexity extensions to G.729 in terms of additional memory usage. It is fully switchable with the 8 kbit/s coder and provides additional flexibility to existing and emerging G.729 applications. The fixed codeboo...

The Dirac codec is a new prototype video coding algorithm from BBC R&D based on wavelet technology. Compression-wise the algorithm is broadly competitive with the state-of-the-art video codecs but computational-wise the execution time is currently poor. One of the large bottlenecks is the arithmetic coder. Hence we took this part under investigation and replaced it with a faster variant, the M-...

This paper describes a 8–32 kb/s embedded speech codec submitted as a candidate for the ITU-T Embedded Variable Bit Rate (EV-VBR) standardization. The coder is built upon a 2-stage coding structure consisting of embedded ACELP coding from 8 to 16kb/s and embedded TCX coding at 24 and 32 kb/s. The coder is designed to support bandwidth scalability (narrow band and wide band signal) and bit-rate ...

We have developed an adaptive multi-rate (AMR) speech coder designed to operate under the GSM digital cellular full rate (22.8 kb/s) and half rate (11.4 kb/s) channels and to maintain high quality in the presence of highly varying background noise and channel conditions. Within each total rate, several codec modes with different source/channel bit rate allocations are used. The speech coders in...

In video-based 3D point cloud compression, the quality of reconstructed depends on both geometry, and color distortions. Finding an optimal allocation total bitrate between geometry coder, coder is a challenging task due to large number possible solutions. To solve this bit problem, we first propose analytical distortion, rate models for information. Using these models, formulate joint problem ...

A modified Orthogonal Frequency Division Multiplexing (OFDM) system for robust progressive image transmission is proposed in this paper. A joint source-channel coder (JSCC) is employed in the modified OFDM system. The set partitioning hierarchical trees (SPIHT) used as source coder, and The Low-Density Parity-Check (LDPC) used as a channel coder. The SPIHT coder is modified to generate four dif...

Problem statement: In spontaneous speech communication, speech coding is an important process that should be taken into account, since the quality of coded speech depends on the efficiency of the speech coding algorithm. As for tonal language which tone plays important role not only on the naturalness and also the intelligibility of the speech, tone must be treated appropriately. Approach: This...

Problem statement: Speech compression is an important issue in the modern digital speech communication. The functionality of bitrates scalability also plays significant role, since the capacity of communication system varies all the time. When considering tonal speech, such as Thai, tone plays important role on the naturalness and the intelligibility of the speech, it must be treated appropriat...